Provided by: samba-common-bin_4.20.4+dfsg-1ubuntu1_amd64 
NAME
smb.conf - The configuration file for the Samba suite
SYNOPSIS
The smb.conf file is a configuration file for the Samba suite. smb.conf contains runtime
configuration information for the Samba programs. The complete description of the file
format and possible parameters held within are here for reference purposes.
HOW CONFIGURATION CHANGES ARE APPLIED
The Samba suite includes a number of different programs. Some of them operate in a client
mode, others are server daemons that provide various services to its clients. The smb.conf
file is processed in the following way:
• The Samba suite's client applications read their configuration only once. Any
changes made after start aren't reflected in the context of already running
client code.
• The Samba suite's server daemons reload their configuration when requested.
However, already active connections do not change their configuration. More
detailed information can be found in smbd(8) and winbindd(8) manual pages.
To request Samba server daemons to refresh their configuration, please use smbcontrol(1)
utility.
FILE FORMAT
The file consists of sections and parameters. A section begins with the name of the
section in square brackets and continues until the next section begins. Sections contain
parameters of the form:
name = value
The file is line-based - that is, each newline-terminated line represents either a
comment, a section name or a parameter.
Section and parameter names are not case sensitive.
Only the first equals sign in a parameter is significant. Whitespace before or after the
first equals sign is discarded. Leading, trailing and internal whitespace in section and
parameter names is irrelevant. Leading and trailing whitespace in a parameter value is
discarded. Internal whitespace within a parameter value is retained verbatim.
Any line beginning with a semicolon (“;”) or a hash (“#”) character is ignored, as are
lines containing only whitespace.
Any line ending in a “\” is continued on the next line in the customary UNIX fashion.
The values following the equals sign in parameters are all either a string (no quotes
needed) or a boolean, which may be given as yes/no, 1/0 or true/false. Case is not
significant in boolean values, but is preserved in string values. Some items such as
create masks are numeric.
SECTION DESCRIPTIONS
Each section in the configuration file (except for the [global] section) describes a
shared resource (known as a “share”). The section name is the name of the shared resource
and the parameters within the section define the shares attributes.
There are three special sections, [global], [homes] and [printers], which are described
under special sections. The following notes apply to ordinary section descriptions.
A share consists of a directory to which access is being given plus a description of the
access rights which are granted to the user of the service. Some housekeeping options are
also specifiable.
Sections are either file share services (used by the client as an extension of their
native file systems) or printable services (used by the client to access print services on
the host running the server).
Sections may be designated guest services, in which case no password is required to access
them. A specified UNIX guest account is used to define access privileges in this case.
Sections other than guest services will require a password to access them. The client
provides the username. As older clients only provide passwords and not usernames, you may
specify a list of usernames to check against the password using the user = option in the
share definition. For modern clients such as Windows 95/98/ME/NT/2000, this should not be
necessary.
The access rights granted by the server are masked by the access rights granted to the
specified or guest UNIX user by the host system. The server does not grant more access
than the host system grants.
The following sample section defines a file space share. The user has write access to the
path /home/bar. The share is accessed via the share name foo:
[foo]
path = /home/bar
read only = no
The following sample section defines a printable share. The share is read-only, but
printable. That is, the only write access permitted is via calls to open, write to and
close a spool file. The guest ok parameter means access will be permitted as the default
guest user (specified elsewhere):
[aprinter]
path = /var/tmp
read only = yes
printable = yes
guest ok = yes
SPECIAL SECTIONS
The [global] section
Parameters in this section apply to the server as a whole, or are defaults for sections
that do not specifically define certain items. See the notes under PARAMETERS for more
information.
The [homes] section
If a section called [homes] is included in the configuration file, services connecting
clients to their home directories can be created on the fly by the server.
When the connection request is made, the existing sections are scanned. If a match is
found, it is used. If no match is found, the requested section name is treated as a
username and looked up in the local password file. If the name exists and the correct
password has been given, a share is created by cloning the [homes] section.
Some modifications are then made to the newly created share:
• The share name is changed from homes to the located username.
• If no path was given, the path is set to the user's home directory.
If you decide to use a path = line in your [homes] section, it may be useful to use the %S
macro. For example:
path = /data/pchome/%S
is useful if you have different home directories for your PCs than for UNIX access.
This is a fast and simple way to give a large number of clients access to their home
directories with a minimum of fuss.
A similar process occurs if the requested section name is “homes”, except that the share
name is not changed to that of the requesting user. This method of using the [homes]
section works well if different users share a client PC.
The [homes] section can specify all the parameters a normal service section can specify,
though some make more sense than others. The following is a typical and suitable [homes]
section:
[homes]
read only = no
An important point is that if guest access is specified in the [homes] section, all home
directories will be visible to all clients without a password. In the very unlikely event
that this is actually desirable, it is wise to also specify read only access.
The browseable flag for auto home directories will be inherited from the global browseable
flag, not the [homes] browseable flag. This is useful as it means setting browseable = no
in the [homes] section will hide the [homes] share but make any auto home directories
visible.
The [printers] section
This section works like [homes], but for printers.
If a [printers] section occurs in the configuration file, users are able to connect to any
printer specified in the local host's printcap file.
When a connection request is made, the existing sections are scanned. If a match is found,
it is used. If no match is found, but a [homes] section exists, it is used as described
above. Otherwise, the requested section name is treated as a printer name and the
appropriate printcap file is scanned to see if the requested section name is a valid
printer share name. If a match is found, a new printer share is created by cloning the
[printers] section.
A few modifications are then made to the newly created share:
• The share name is set to the located printer name
• If no printer name was given, the printer name is set to the located printer
name
• If the share does not permit guest access and no username was given, the
username is set to the located printer name.
The [printers] service MUST be printable - if you specify otherwise, the server will
refuse to load the configuration file.
Typically the path specified is that of a world-writeable spool directory with the sticky
bit set on it. A typical [printers] entry looks like this:
[printers]
path = /var/tmp
guest ok = yes
printable = yes
All aliases given for a printer in the printcap file are legitimate printer names as far
as the server is concerned. If your printing subsystem doesn't work like that, you will
have to set up a pseudo-printcap. This is a file consisting of one or more lines like
this:
alias|alias|alias|alias...
Each alias should be an acceptable printer name for your printing subsystem. In the
[global] section, specify the new file as your printcap. The server will only recognize
names found in your pseudo-printcap, which of course can contain whatever aliases you
like. The same technique could be used simply to limit access to a subset of your local
printers.
An alias, by the way, is defined as any component of the first entry of a printcap record.
Records are separated by newlines, components (if there are more than one) are separated
by vertical bar symbols (|).
Note
On SYSV systems which use lpstat to determine what printers are defined on the system
you may be able to use printcap name = lpstat to automatically obtain a list of
printers. See the printcap name option for more details.
USERSHARES
Starting with Samba version 3.0.23 the capability for non-root users to add, modify, and
delete their own share definitions has been added. This capability is called usershares
and is controlled by a set of parameters in the [global] section of the smb.conf. The
relevant parameters are :
usershare allow guests
Controls if usershares can permit guest access.
usershare max shares
Maximum number of user defined shares allowed.
usershare owner only
If set only directories owned by the sharing user can be shared.
usershare path
Points to the directory containing the user defined share definitions. The filesystem
permissions on this directory control who can create user defined shares.
usershare prefix allow list
Comma-separated list of absolute pathnames restricting what directories can be shared.
Only directories below the pathnames in this list are permitted.
usershare prefix deny list
Comma-separated list of absolute pathnames restricting what directories can be shared.
Directories below the pathnames in this list are prohibited.
usershare template share
Names a pre-existing share used as a template for creating new usershares. All other
share parameters not specified in the user defined share definition are copied from
this named share.
To allow members of the UNIX group foo to create user defined shares, create the directory
to contain the share definitions as follows:
Become root:
mkdir /usr/local/samba/lib/usershares
chgrp foo /usr/local/samba/lib/usershares
chmod 1770 /usr/local/samba/lib/usershares
Then add the parameters
usershare path = /usr/local/samba/lib/usershares
usershare max shares = 10 # (or the desired number of shares)
to the global section of your smb.conf. Members of the group foo may then manipulate the
user defined shares using the following commands.
net usershare add sharename path [comment] [acl] [guest_ok=[y|n]]
To create or modify (overwrite) a user defined share.
net usershare delete sharename
To delete a user defined share.
net usershare list wildcard-sharename
To list user defined shares.
net usershare info wildcard-sharename
To print information about user defined shares.
PARAMETERS
Parameters define the specific attributes of sections.
Some parameters are specific to the [global] section (e.g., security). Some parameters are
usable in all sections (e.g., create mask). All others are permissible only in normal
sections. For the purposes of the following descriptions the [homes] and [printers]
sections will be considered normal. The letter G in parentheses indicates that a parameter
is specific to the [global] section. The letter S indicates that a parameter can be
specified in a service specific section. All S parameters can also be specified in the
[global] section - in which case they will define the default behavior for all services.
Parameters are arranged here in alphabetical order - this may not create best bedfellows,
but at least you can find them! Where there are synonyms, the preferred synonym is
described, others refer to the preferred synonym.
VARIABLE SUBSTITUTIONS
Many of the strings that are settable in the config file can take substitutions. For
example the option “path = /tmp/%u” is interpreted as “path = /tmp/john” if the user
connected with the username john.
These substitutions are mostly noted in the descriptions below, but there are some general
substitutions which apply whenever they might be relevant. These are:
%U
session username (the username that the client wanted, not necessarily the same as the
one they got).
%G
primary group name of %U.
%h
the Internet hostname that Samba is running on.
%m
the NetBIOS name of the client machine (very useful).
This parameter is not available when Samba listens on port 445, as clients no longer
send this information. If you use this macro in an include statement on a domain that
has a Samba domain controller be sure to set in the [global] section smb ports = 139.
This will cause Samba to not listen on port 445 and will permit include functionality
to function as it did with Samba 2.x.
%L
the NetBIOS name of the server. This allows you to change your config based on what
the client calls you. Your server can have a “dual personality”.
%M
the Internet name of the client machine.
%R
the selected protocol level after protocol negotiation. It can be one of CORE,
COREPLUS, LANMAN1, LANMAN2, NT1, SMB2_02, SMB2_10, SMB3_00, SMB3_02, SMB3_11 or
SMB2_FF.
%d
the process id of the current server process.
%a
The architecture of the remote machine. It currently recognizes Samba (Samba), the
Linux CIFS file system (CIFSFS), OS/2, (OS2), Mac OS X (OSX), Windows for Workgroups
(WfWg), Windows 9x/ME (Win95), Windows NT (WinNT), Windows 2000 (Win2K), Windows XP
(WinXP), Windows XP 64-bit(WinXP64), Windows 2003 including 2003R2 (Win2K3), and
Windows Vista (Vista). Anything else will be known as UNKNOWN.
%I
the IP address of the client machine.
Before 4.0.0 it could contain IPv4 mapped IPv6 addresses, now it only contains IPv4 or
IPv6 addresses.
%J
the IP address of the client machine, colons/dots replaced by underscores.
%i
the local IP address to which a client connected.
Before 4.0.0 it could contain IPv4 mapped IPv6 addresses, now it only contains IPv4 or
IPv6 addresses.
%j
the local IP address to which a client connected, colons/dots replaced by underscores.
%T
the current date and time.
%t
the current date and time in a minimal format without colons (YYYYYmmdd_HHMMSS).
%D
name of the domain or workgroup of the current user.
%w
the winbind separator.
%$(envvar)
the value of the environment variable envar.
The following substitutes apply only to some configuration options (only those that are
used when a connection has been established):
%S
the name of the current service, if any.
%P
the root directory of the current service, if any.
%u
username of the current service, if any.
%g
primary group name of %u.
%H
the home directory of the user given by %u.
%N
This value is the same as %L.
There are some quite creative things that can be done with these substitutions and other
smb.conf options.
NAME MANGLING
Samba supports name mangling so that DOS and Windows clients can use files that don't
conform to the 8.3 format. It can also be set to adjust the case of 8.3 format filenames.
There are several options that control the way mangling is performed, and they are grouped
here rather than listed separately. For the defaults look at the output of the testparm
program.
These options can be set separately for each service.
The options are:
case sensitive = yes/no/auto
controls whether filenames are case sensitive. If they aren't, Samba must do a
filename search and match on passed names. The default setting of auto allows clients
that support case sensitive filenames (Linux CIFSVFS and smbclient 3.0.5 and above
currently) to tell the Samba server on a per-packet basis that they wish to access the
file system in a case-sensitive manner (to support UNIX case sensitive semantics). No
Windows or DOS system supports case-sensitive filename so setting this option to auto
is the same as setting it to no for them. Default auto.
default case = upper/lower
controls what the default case is for new filenames (ie. files that don't currently
exist in the filesystem). Default lower. IMPORTANT NOTE: As part of the optimizations
for directories containing large numbers of files, the following special case applies.
If the options case sensitive = yes, preserve case = No, and short preserve case = No
are set, then the case of all incoming client filenames, not just new filenames, will
be modified. See additional notes below.
preserve case = yes/no
controls whether new files (ie. files that don't currently exist in the filesystem)
are created with the case that the client passes, or if they are forced to be the
default case. Default yes.
short preserve case = yes/no
controls if new files (ie. files that don't currently exist in the filesystem) which
conform to 8.3 syntax, that is all in upper case and of suitable length, are created
upper case, or if they are forced to be the default case. This option can be used with
preserve case = yes to permit long filenames to retain their case, while short names
are lowercased. Default yes.
By default, Samba 3.0 has the same semantics as a Windows NT server, in that it is case
insensitive but case preserving. As a special case for directories with large numbers of
files, if the case options are set as follows, "case sensitive = yes", "case preserve =
no", "short preserve case = no" then the "default case" option will be applied and will
modify all filenames sent from the client when accessing this share.
REGISTRY-BASED CONFIGURATION
Starting with Samba version 3.2.0, the capability to store Samba configuration in the
registry is available. The configuration is stored in the registry key
HKLM\Software\Samba\smbconf. There are two levels of registry configuration:
1. Share definitions stored in registry are used. This is triggered by setting the
global parameter registry shares to “yes” in smb.conf.
The registry shares are loaded not at startup but on demand at runtime by smbd.
Shares defined in smb.conf take priority over shares of the same name defined
in registry.
2. Global smb.conf options stored in registry are used. This can be activated in
two different ways:
Firstly, a registry only configuration is triggered by setting config backend =
registry in the [global] section of smb.conf. This resets everything that has
been read from config files to this point and reads the content of the global
configuration section from the registry. This is the recommended method of
using registry based configuration.
Secondly, a mixed configuration can be activated by a special new meaning of
the parameter include = registry in the [global] section of smb.conf. This
reads the global options from registry with the same priorities as for an
include of a text file. This may be especially useful in cases where an initial
configuration is needed to access the registry.
Activation of global registry options automatically activates registry shares.
So in the registry only case, shares are loaded on demand only.
Note: To make registry-based configurations foolproof at least to a certain extent, the
use of lock directory and config backend inside the registry configuration has been
disabled: Especially by changing the lock directory inside the registry configuration, one
would create a broken setup where the daemons do not see the configuration they loaded
once it is active.
The registry configuration can be accessed with tools like regedit or net (rpc) registry
in the key HKLM\Software\Samba\smbconf. More conveniently, the conf subcommand of the
net(8) utility offers a dedicated interface to read and write the registry based
configuration locally, i.e. directly accessing the database file, circumventing the
server.
IDENTITY MAPPING CONSIDERATIONS
In the SMB protocol, users, groups, and machines are represented by their security
identifiers (SIDs). On POSIX system Samba processes need to run under corresponding POSIX
user identities and with supplemental POSIX groups to allow access to the files owned by
those users and groups. The process of mapping SIDs to POSIX users and groups is called
IDENTITY MAPPING or, in short, ID MAPPING.
Samba supports multiple ways to map SIDs to POSIX users and groups. The configuration is
driven by the idmap config DOMAIN : OPTION option which allows one to specify identity
mapping (idmap) options for each domain separately.
Identity mapping modules implement different strategies for mapping of SIDs to POSIX user
and group identities. They are applicable to different use cases and scenarios. It is
advised to read the documentation of the individual identity mapping modules before
choosing a specific scenario to use. Each identity management module is documented in a
separate manual page. The standard idmap backends are tdb (idmap_tdb(8)), tdb2
(idmap_tdb2(8)), ldap (idmap_ldap(8)), rid (idmap_rid(8)), hash (idmap_hash(8)), autorid
(idmap_autorid(8)), ad (idmap_ad(8)), nss (idmap_nss(8)), and rfc2307 (idmap_rfc2307(8)).
Overall, ID mapping configuration should be decided carefully. Changes to the already
deployed ID mapping configuration may create the risk of losing access to the data or
disclosing the data to the wrong parties.
This example shows how to configure two domains with idmap_rid(8), the principal domain
and a trusted domain, leaving the default id mapping scheme at tdb.
[global]
security = domain
workgroup = MAIN
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999
idmap config MAIN : backend = rid
idmap config MAIN : range = 5000000-5999999
idmap config TRUSTED : backend = rid
idmap config TRUSTED : range = 6000000-6999999
EXPLANATION OF EACH PARAMETER
abort shutdown script (G)
This a full path name to a script called by smbd(8) that should stop a shutdown
procedure issued by the shutdown script.
If the connected user possesses the SeRemoteShutdownPrivilege, right, this command
will be run as root.
Default: abort shutdown script = ""
Example: abort shutdown script = /sbin/shutdown -c
access based share enum (S)
If this parameter is yes for a service, then the share hosted by the service will only
be visible to users who have read or write access to the share during share
enumeration (for example net view \\sambaserver). The share ACLs which allow or deny
the access to the share can be modified using for example the sharesec command or
using the appropriate Windows tools. This has parallels to access based enumeration,
the main difference being that only share permissions are evaluated, and security
descriptors on files contained on the share are not used in computing enumeration
access rights.
Default: access based share enum = no
acl allow execute always (S)
This boolean parameter controls the behaviour of smbd(8) when receiving a protocol
request of "open for execution" from a Windows client. With Samba 3.6 and older, the
execution right in the ACL was not checked, so a client could execute a file even if
it did not have execute rights on the file. In Samba 4.0, this has been fixed, so that
by default, i.e. when this parameter is set to "False", "open for execution" is now
denied when execution permissions are not present.
If this parameter is set to "True", Samba does not check execute permissions on "open
for execution", thus re-establishing the behaviour of Samba 3.6. This can be useful to
smoothen upgrades from older Samba versions to 4.0 and newer. This setting is not
meant to be used as a permanent setting, but as a temporary relief: It is recommended
to fix the permissions in the ACLs and reset this parameter to the default after a
certain transition period.
Default: acl allow execute always = no
acl check permissions (S)
Please note this parameter is now deprecated in Samba 3.6.2 and will be removed in a
future version of Samba.
This boolean parameter controls what smbd(8) does on receiving a protocol request of
"open for delete" from a Windows client. If a Windows client doesn't have permissions
to delete a file then they expect this to be denied at open time. POSIX systems
normally only detect restrictions on delete by actually attempting to delete the file
or directory. As Windows clients can (and do) "back out" a delete request by unsetting
the "delete on close" bit Samba cannot delete the file immediately on "open for
delete" request as we cannot restore such a deleted file. With this parameter set to
true (the default) then smbd checks the file system permissions directly on "open for
delete" and denies the request without actually deleting the file if the file system
permissions would seem to deny it. This is not perfect, as it's possible a user could
have deleted a file without Samba being able to check the permissions correctly, but
it is close enough to Windows semantics for mostly correct behaviour. Samba will
correctly check POSIX ACL semantics in this case.
If this parameter is set to "false" Samba doesn't check permissions on "open for
delete" and allows the open. If the user doesn't have permission to delete the file
this will only be discovered at close time, which is too late for the Windows user
tools to display an error message to the user. The symptom of this is files that
appear to have been deleted "magically" re-appearing on a Windows explorer refresh.
This is an extremely advanced protocol option which should not need to be changed.
This parameter was introduced in its final form in 3.0.21, an earlier version with
slightly different semantics was introduced in 3.0.20. That older version is not
documented here.
Default: acl check permissions = yes
acl claims evaluation (G)
This option controls the way Samba handles evaluation of security descriptors in
Samba, with regards to Active Directory Claims. AD Claims, introduced with Windows
2012, are essentially administrator-defined key-value pairs that can be set both in
Active Directory (communicated via the Kerberos PAC) and in the security descriptor
themselves.
Active Directory claims are new with Samba 4.20. Because the claims are evaluated
against a very flexible expression language within the security descriptor, this
option provides a mechanism to disable this logic if required by the administrator.
This default behaviour is that claims evaluation is enabled in the AD DC only.
Additionally, claims evaluation on the AD DC is only enabled if the DC functional
level is 2012 or later. See ad dc functional level.
Possible values are :
• AD DC only: Enabled for the Samba AD DC (for DC functional level 2012 or
higher).
• never: Disabled in all cases. This option disables some but not all of the
Authentication Policies and Authentication Policy Silos features of the
Windows 2012R2 functional level in the AD DC.
Default: acl claims evaluation = AD DC only
acl flag inherited canonicalization (S)
This option controls the way Samba handles client requests setting the Security
Descriptor of files and directories and the effect the operation has on the Security
Descriptor flag "DACL auto-inherited" (DI). Generally, this flag is set on a file (or
directory) upon creation if the parent directory has DI set and also has inheritable
ACEs.
On the other hand when a Security Descriptor is explicitly set on a file, the DI flag
is cleared, unless the flag "DACL Inheritance Required" (DR) is also set in the new
Security Descriptor (fwiw, DR is never stored on disk).
This is the default behaviour when this option is enabled (the default). When setting
this option to no, the resulting value of the DI flag on-disk is directly taken from
the DI value of the to-be-set Security Descriptor. This can be used so dump tools like
rsync that copy data blobs from xattrs that represent ACLs created by the acl_xattr
VFS module will result in copies of the ACL that are identical to the source. Without
this option, the copied ACLs would all lose the DI flag if set on the source.
Default: acl flag inherited canonicalization = yes
acl group control (S)
In a POSIX filesystem, only the owner of a file or directory and the superuser can
modify the permissions and ACLs on a file. If this parameter is set, then Samba
overrides this restriction, and also allows the primary group owner of a file or
directory to modify the permissions and ACLs on that file.
On a Windows server, groups may be the owner of a file or directory - thus allowing
anyone in that group to modify the permissions on it. This allows the delegation of
security controls on a point in the filesystem to the group owner of a directory and
anything below it also owned by that group. This means there are multiple people with
permissions to modify ACLs on a file or directory, easing manageability.
This parameter allows Samba to also permit delegation of the control over a point in
the exported directory hierarchy in much the same way as Windows. This allows all
members of a UNIX group to control the permissions on a file or directory they have
group ownership on.
This parameter is best used with the inherit owner option and also on a share
containing directories with the UNIX setgid bit set on them, which causes new files
and directories created within it to inherit the group ownership from the containing
directory.
This parameter was deprecated in Samba 3.0.23, but re-activated in Samba 3.0.31 and
above, as it now only controls permission changes if the user is in the owning primary
group. It is now no longer equivalent to the dos filemode option.
Default: acl group control = no
acl map full control (S)
This boolean parameter controls whether smbd(8) maps a POSIX ACE entry of "rwx"
(read/write/execute), the maximum allowed POSIX permission set, into a Windows ACL of
"FULL CONTROL". If this parameter is set to true any POSIX ACE entry of "rwx" will be
returned in a Windows ACL as "FULL CONTROL", is this parameter is set to false any
POSIX ACE entry of "rwx" will be returned as the specific Windows ACL bits
representing read, write and execute.
Default: acl map full control = yes
ad dc functional level (G)
The value of the parameter (a string) is the Active Directory functional level that
this Domain Controller will claim to support.
Possible values are :
• 2008_R2: Similar to Windows 2008 R2 Functional Level
• 2012: Similar to Windows 2012 Functional Level
• 2012_R2: Similar to Windows 2012 R2 Functional Level
• 2016: Similar to Windows 2016 Functional Level
Normally this option should not be set as Samba will operate per the released
functionality of the Samba Active Directory Domain Controller.
However to access incomplete features in domain functional level 2016 it may be useful
to set this value, prior to upgrading the domain functional level.
If this is set manually, the protection against mismatching features between domain
controllers is reduced, so all domain controllers should be running the same version
of Samba, to ensure that behaviour as seen by the client is the same no matter which
DC is contacted.
Setting this to 2016 will allow raising the domain functional level with samba-tool
domain level raise --domain-level=2016 and provide access to Samba's Kerberos Claims
and Dynamic Access Control feature.
Warning
The Samba's Kerberos Claims and Dynamic Access Control features enabled with 2016
are incomplete in Samba 4.19.
Default: ad dc functional level = 2008_R2
Example: ad dc functional level = 2016
add group script (G)
This is the full pathname to a script that will be run AS ROOT by smbd(8) when a new
group is requested. It will expand any %g to the group name passed. This script is
only useful for installations using the Windows NT domain administration tools. The
script is free to create a group with an arbitrary name to circumvent unix group name
restrictions. In that case the script must print the numeric gid of the created group
on stdout.
Default: add group script =
Example: add group script = /usr/sbin/groupadd %g
additional dns hostnames (G)
A list of additional DNS names by which this host can be identified
Default: additional dns hostnames = # empty string (no additional dns names)
Example: additional dns hostnames = host2.example.com host3.other.com
add machine script (G)
This is the full pathname to a script that will be run by smbd(8) when a machine is
added to Samba's domain and a Unix account matching the machine's name appended with a
"$" does not already exist.
This option is very similar to the add user script, and likewise uses the %u
substitution for the account name. Do not use the %m substitution.
Default: add machine script =
Example: add machine script = /usr/sbin/adduser -n -g machines -c Machine -d
/var/lib/nobody -s /bin/false %u
addport command (G)
Samba 3.0.23 introduced support for adding printer ports remotely using the Windows
"Add Standard TCP/IP Port Wizard". This option defines an external program to be
executed when smbd receives a request to add a new Port to the system. The script is
passed two parameters:
• port name
• device URI
The deviceURI is in the format of socket://<hostname>[:<portnumber>] or
lpd://<hostname>/<queuename>.
Default: addport command =
Example: addport command = /etc/samba/scripts/addport.sh
addprinter command (G)
With the introduction of MS-RPC based printing support for Windows NT/2000 clients in
Samba 2.2, The MS Add Printer Wizard (APW) icon is now also available in the
"Printers..." folder displayed a share listing. The APW allows for printers to be add
remotely to a Samba or Windows NT/2000 print server.
For a Samba host this means that the printer must be physically added to the
underlying printing system. The addprinter command defines a script to be run which
will perform the necessary operations for adding the printer to the print system and
to add the appropriate service definition to the smb.conf file in order that it can be
shared by smbd(8).
The addprinter command is automatically invoked with the following parameter (in
order):
• printer name
• share name
• port name
• driver name
• location
• Windows 9x driver location
All parameters are filled in from the PRINTER_INFO_2 structure sent by the Windows
NT/2000 client with one exception. The "Windows 9x driver location" parameter is
included for backwards compatibility only. The remaining fields in the structure are
generated from answers to the APW questions.
Once the addprinter command has been executed, smbd will reparse the smb.conf to
determine if the share defined by the APW exists. If the sharename is still invalid,
then smbd will return an ACCESS_DENIED error to the client.
The addprinter command program can output a single line of text, which Samba will set
as the port the new printer is connected to. If this line isn't output, Samba won't
reload its printer shares.
Default: addprinter command =
Example: addprinter command = /usr/bin/addprinter
add share command (G)
Samba 2.2.0 introduced the ability to dynamically add and delete shares via the
Windows NT 4.0 Server Manager. The add share command is used to define an external
program or script which will add a new service definition to smb.conf.
In order to successfully execute the add share command, smbd requires that the
administrator connects using a root account (i.e. uid == 0) or has the
SeDiskOperatorPrivilege. Scripts defined in the add share command parameter are
executed as root.
When executed, smbd will automatically invoke the add share command with five
parameters.
• configFile - the location of the global smb.conf file.
• shareName - the name of the new share.
• pathName - path to an **existing** directory on disk.
• comment - comment string to associate with the new share.
• max connections Number of maximum simultaneous connections to this share.
This parameter is only used to add file shares. To add printer shares, see the
addprinter command.
Default: add share command =
Example: add share command = /usr/local/bin/addshare
add user script (G)
This is the full pathname to a script that will be run AS ROOT by smbd(8) under
special circumstances described below.
Normally, a Samba server requires that UNIX users are created for all users accessing
files on this server. For sites that use Windows NT account databases as their primary
user database creating these users and keeping the user list in sync with the Windows
NT PDC is an onerous task. This option allows smbd to create the required UNIX users
ON DEMAND when a user accesses the Samba server.
When the Windows user attempts to access the Samba server, at login (session setup in
the SMB protocol) time, smbd(8) contacts the password server and attempts to
authenticate the given user with the given password. If the authentication succeeds
then smbd attempts to find a UNIX user in the UNIX password database to map the
Windows user into. If this lookup fails, and add user script is set then smbd will
call the specified script AS ROOT, expanding any %u argument to be the user name to
create.
If this script successfully creates the user then smbd will continue on as though the
UNIX user already existed. In this way, UNIX users are dynamically created to match
existing Windows NT accounts.
See also security, password server, delete user script.
Default: add user script =
Example: add user script = /usr/local/samba/bin/add_user %u
add user to group script (G)
Full path to the script that will be called when a user is added to a group using the
Windows NT domain administration tools. It will be run by smbd(8) AS ROOT. Any %g will
be replaced with the group name and any %u will be replaced with the user name.
Note that the adduser command used in the example below does not support the used
syntax on all systems.
Default: add user to group script =
Example: add user to group script = /usr/sbin/adduser %u %g
administrative share (S)
If this parameter is set to yes for a share, then the share will be an administrative
share. The Administrative Shares are the default network shares created by all Windows
NT-based operating systems. These are shares like C$, D$ or ADMIN$. The type of these
shares is STYPE_DISKTREE_HIDDEN.
See the section below on security for more information about this option.
Default: administrative share = no
admin users (S)
This is a list of users who will be granted administrative privileges on the share.
This means that they will do all file operations as the super-user (root).
You should use this option very carefully, as any user in this list will be able to do
anything they like on the share, irrespective of file permissions.
Default: admin users =
Example: admin users = jason
afs share (S)
This parameter controls whether special AFS features are enabled for this share. If
enabled, it assumes that the directory exported via the path parameter is a local AFS
import. The special AFS features include the attempt to hand-craft an AFS token if you
enabled --with-fake-kaserver in configure.
Default: afs share = no
afs token lifetime (G)
This parameter controls the lifetime of tokens that the AFS fake-kaserver claims. In
reality these never expire but this lifetime controls when the afs client will forget
the token.
Set this parameter to 0 to get NEVERDATE.
Default: afs token lifetime = 604800
afs username map (G)
If you are using the fake kaserver AFS feature, you might want to hand-craft the
usernames you are creating tokens for. For example this is necessary if you have users
from several domain in your AFS Protection Database. One possible scheme to code users
as DOMAIN+User as it is done by winbind with the + as a separator.
The mapped user name must contain the cell name to log into, so without setting this
parameter there will be no token.
Default: afs username map =
Example: afs username map = %u@afs.samba.org
aio max threads (G)
The integer parameter specifies the maximum number of threads each smbd process will
create when doing parallel asynchronous IO calls. If the number of outstanding calls
is greater than this number the requests will not be refused but go onto a queue and
will be scheduled in turn as outstanding requests complete.
Related command: aio read size
Related command: aio write size
Default: aio max threads = 100
aio read size (S)
If this integer parameter is set to a non-zero value, Samba will read from files
asynchronously when the request size is bigger than this value. Note that it happens
only for non-chained and non-chaining reads.
The only reasonable values for this parameter are 0 (no async I/O) and 1 (always do
async I/O).
Related command: aio write size
Default: aio read size = 1
Example: aio read size = 0 # Always do reads synchronously
aio write behind (S)
If Samba has been built with asynchronous I/O support, Samba will not wait until write
requests are finished before returning the result to the client for files listed in
this parameter. Instead, Samba will immediately return that the write request has been
finished successfully, no matter if the operation will succeed or not. This might
speed up clients without aio support, but is really dangerous, because data could be
lost and files could be damaged.
The syntax is identical to the veto files parameter.
Default: aio write behind =
Example: aio write behind = /*.tmp/
aio write size (S)
If this integer parameter is set to a non-zero value, Samba will write to files
asynchronously when the request size is bigger than this value. Note that it happens
only for non-chained and non-chaining writes.
The only reasonable values for this parameter are 0 (no async I/O) and 1 (always do
async I/O).
Compared to aio read size this parameter has a smaller effect, most writes should end
up in the file system cache. Writes that require space allocation might benefit most
from going asynchronous.
Related command: aio read size
Default: aio write size = 1
Example: aio write size = 0 # Always do writes synchronously
algorithmic rid base (G)
This determines how Samba will use its algorithmic mapping from uids/gid to the RIDs
needed to construct NT Security Identifiers.
Setting this option to a larger value could be useful to sites transitioning from
WinNT and Win2k, as existing user and group rids would otherwise clash with system
users etc.
All UIDs and GIDs must be able to be resolved into SIDs for the correct operation of
ACLs on the server. As such the algorithmic mapping can't be 'turned off', but pushing
it 'out of the way' should resolve the issues. Users and groups can then be assigned
'low' RIDs in arbitrary-rid supporting backends.
Default: algorithmic rid base = 1000
Example: algorithmic rid base = 100000
allocation roundup size (S)
This parameter allows an administrator to tune the allocation size reported to Windows
clients. This is only useful for old SMB1 clients because modern SMB dialects
eliminated that bottleneck and have better performance by default. Using this
parameter may cause difficulties for some applications, e.g. MS Visual Studio. If the
MS Visual Studio compiler starts to crash with an internal error, set this parameter
to zero for this share. Settings this parameter to a large value can also cause small
files to allocate more space on the disk than needed.
This parameter is deprecated and will be removed in one of the next Samba releases.
The integer parameter specifies the roundup size in bytes.
Default: allocation roundup size = 0
Example: allocation roundup size = 1048576 # (to set it to the former default of 1
MiB)
allow dcerpc auth level connect (G)
This option controls whether DCERPC services are allowed to be used with
DCERPC_AUTH_LEVEL_CONNECT, which provides authentication, but no per message integrity
nor privacy protection.
Some interfaces like samr, lsarpc and netlogon have a hard-coded default of no and
epmapper, mgmt and rpcecho have a hard-coded default of yes.
The behavior can be overwritten per interface name (e.g. lsarpc, netlogon, samr,
srvsvc, winreg, wkssvc ...) by using 'allow dcerpc auth level connect:interface = yes'
as option.
This option is over-ridden by the implementation specific restrictions. E.g. the
drsuapi and backupkey protocols require DCERPC_AUTH_LEVEL_PRIVACY. The dnsserver
protocol requires DCERPC_AUTH_LEVEL_INTEGRITY.
Default: allow dcerpc auth level connect = no
Example: allow dcerpc auth level connect = yes
allow dns updates (G)
This option determines what kind of updates to the DNS are allowed.
DNS updates can either be disallowed completely by setting it to disabled, enabled
over secure connections only by setting it to secure only or allowed in all cases by
setting it to nonsecure.
Default: allow dns updates = secure only
Example: allow dns updates = disabled
allow insecure wide links (G)
In normal operation the option wide links which allows the server to follow symlinks
outside of a share path is automatically disabled when unix extensions are enabled on
a Samba server. This is done for security purposes to prevent UNIX clients creating
symlinks to areas of the server file system that the administrator does not wish to
export.
Setting allow insecure wide links to true disables the link between these two
parameters, removing this protection and allowing a site to configure the server to
follow symlinks (by setting wide links to "true") even when unix extensions is turned
on.
It is not recommended to enable this option unless you fully understand the
implications of allowing the server to follow symbolic links created by UNIX clients.
For most normal Samba configurations this would be considered a security hole and
setting this parameter is not recommended.
This option was added at the request of sites who had deliberately set Samba up in
this way and needed to continue supporting this functionality without having to patch
the Samba code.
Default: allow insecure wide links = no
allow nt4 crypto (G)
This option is deprecated and will be removed in future, as it is a security problem
if not set to "no" (which will be the hardcoded behavior in future).
This option controls whether the netlogon server (currently only in 'active directory
domain controller' mode), will reject clients which do not support
NETLOGON_NEG_STRONG_KEYS nor NETLOGON_NEG_SUPPORTS_AES.
This option was added with Samba 4.2.0. It may lock out clients which worked fine with
Samba versions up to 4.1.x. as the effective default was "yes" there, while it is "no"
now.
If you have clients without RequireStrongKey = 1 in the registry, you may need to set
"allow nt4 crypto = yes", until you have fixed all clients.
"allow nt4 crypto = yes" allows weak crypto to be negotiated, maybe via downgrade
attacks.
Avoid using this option! Use explicit 'allow nt4 crypto:COMPUTERACCOUNT = yes'
instead! Which is available with the patches for CVE-2022-38023 see
https://bugzilla.samba.org/show_bug.cgi?id=15240
Samba will log an error in the log files at log level 0 if legacy a client is rejected
or allowed without an explicit, 'allow nt4 crypto:COMPUTERACCOUNT = yes' option for
the client. The message will indicate the explicit 'allow nt4 crypto:COMPUTERACCOUNT =
yes' line to be added, if the legacy client software requires it. (The log level can
be adjusted with 'CVE_2022_38023:error_debug_level = 1' in order to complain only at a
higher log level).
This allows admins to use "yes" only for a short grace period, in order to collect the
explicit 'allow nt4 crypto:COMPUTERACCOUNT = yes' options.
This option is over-ridden by the effective value of 'yes' from the 'server reject md5
schannel:COMPUTERACCOUNT' and/or 'reject md5 clients' options.
Default: allow nt4 crypto = no
allow nt4 crypto:COMPUTERACCOUNT (G)
If you still have legacy domain members which required 'allow nt4 crypto = yes', it is
possible to specify an explicit exception per computer account by using 'allow nt4
crypto:COMPUTERACCOUNT = yes' as option. Note that COMPUTERACCOUNT has to be the
sAMAccountName value of the computer account (including the trailing '$' sign).
Samba will log a complaint in the log files at log level 0 about the security problem
if the option is set to "yes", but the related computer does not require it. (The log
level can be adjusted with 'CVE_2022_38023:warn_about_unused_debug_level = 1' in order
to complain only at a higher log level).
Samba will log a warning in the log files at log level 5, if a setting is still needed
for the specified computer account.
See CVE-2022-38023, https://bugzilla.samba.org/show_bug.cgi?id=15240.
This option overrides the allow nt4 crypto option.
This option is over-ridden by the effective value of 'yes' from the 'server reject md5
schannel:COMPUTERACCOUNT' and/or 'reject md5 clients' options.
Which means 'allow nt4 crypto:COMPUTERACCOUNT = yes' is only useful in combination
with 'server reject md5 schannel:COMPUTERACCOUNT = no'
allow nt4 crypto:LEGACYCOMPUTER1$ = yes
server reject md5 schannel:LEGACYCOMPUTER1$ = no
allow nt4 crypto:NASBOX$ = yes
server reject md5 schannel:NASBOX$ = no
allow nt4 crypto:LEGACYCOMPUTER2$ = yes
server reject md5 schannel:LEGACYCOMPUTER2$ = no
No default
allow trusted domains (G)
This option only takes effect when the security option is set to server, domain or
ads. If it is set to no, then attempts to connect to a resource from a domain or
workgroup other than the one which smbd is running in will fail, even if that domain
is trusted by the remote server doing the authentication.
This is useful if you only want your Samba server to serve resources to users in the
domain it is a member of. As an example, suppose that there are two domains DOMA and
DOMB. DOMB is trusted by DOMA, which contains the Samba server. Under normal
circumstances, a user with an account in DOMB can then access the resources of a UNIX
account with the same account name on the Samba server even if they do not have an
account in DOMA. This can make implementing a security boundary difficult.
Default: allow trusted domains = yes
allow unsafe cluster upgrade (G)
If set to no (the default), smbd checks at startup if other smbd versions are running
in the cluster and refuses to start if so. This is done to protect data corruption in
internal data structures due to incompatible Samba versions running concurrently in
the same cluster. Setting this parameter to yes disables this safety check.
Default: allow unsafe cluster upgrade = no
apply group policies (G)
This option controls whether winbind will execute the gpupdate command defined in gpo
update command on the Group Policy update interval. The Group Policy update interval
is defined as every 90 minutes, plus a random offset between 0 and 30 minutes. This
applies Group Policy Machine polices to the client or KDC and machine policies to a
server.
Default: apply group policies = no
Example: apply group policies = yes
async dns timeout (G)
The number of seconds the asynchronous DNS resolver code in Samba will wait for
responses. Some of the Samba client library code uses internal asynchronous DNS
resolution for A and AAAA records when trying to find Active Directory Domain
controllers. This value prevents this name resolution code from waiting for DNS server
timeouts.
The minimum value of this parameter is clamped at 1 second.
Default: async dns timeout = 10
Example: async dns timeout = 20
async smb echo handler (G)
This parameter specifies whether Samba should fork the async smb echo handler. It can
be beneficial if your file system can block syscalls for a very long time. In some
circumstances, it prolongs the timeout that Windows uses to determine whether a
connection is dead. This parameter is only for SMB1. For SMB2 and above TCP keepalives
can be used instead.
Default: async smb echo handler = no
auth event notification (G)
When enabled, this option causes Samba (acting as an Active Directory Domain
Controller) to stream authentication events across the internal message bus. Scripts
built using Samba's python bindings can listen to these events by registering as the
service auth_event.
This is not needed for the audit logging described in log level.
Instead, this should instead be considered a developer option (it assists in the Samba
testsuite) rather than a facility for external auditing, as message delivery is not
guaranteed (a feature that the testsuite works around).
The authentication events are also logged via the normal logging methods when the log
level is set appropriately, say to auth_json_audit:3.
Default: auth event notification = no
preload
This parameter is a synonym for auto services.
auto services (G)
This is a list of services that you want to be automatically added to the browse
lists. This is most useful for homes and printers services that would otherwise not be
visible.
Note that if you just want all printers in your printcap file loaded then the load
printers option is easier.
Default: auto services =
Example: auto services = fred lp colorlp
available (S)
This parameter lets you "turn off" a service. If available = no, then ALL attempts to
connect to the service will fail. Such failures are logged.
Default: available = yes
bind dns directory
This parameter is a synonym for binddns dir.
binddns dir (G)
This parameters defines the directory samba will use to store the configuration files
for bind, such as named.conf. NOTE: The bind dns directory needs to be on the same
mount point as the private directory!
Default: binddns dir = /var/lib/samba/bind-dns
bind interfaces only (G)
This global parameter allows the Samba admin to limit what interfaces on a machine
will serve SMB requests. It affects file service smbd(8) and name service nmbd(8) in a
slightly different ways.
For name service it causes nmbd to bind to ports 137 and 138 on the interfaces listed
in the interfaces parameter. nmbd also binds to the "all addresses" interface
(0.0.0.0) on ports 137 and 138 for the purposes of reading broadcast messages. If this
option is not set then nmbd will service name requests on all of these sockets. If
bind interfaces only is set then nmbd will check the source address of any packets
coming in on the broadcast sockets and discard any that don't match the broadcast
addresses of the interfaces in the interfaces parameter list. As unicast packets are
received on the other sockets it allows nmbd to refuse to serve names to machines that
send packets that arrive through any interfaces not listed in the interfaces list. IP
Source address spoofing does defeat this simple check, however, so it must not be used
seriously as a security feature for nmbd.
For file service it causes smbd(8) to bind only to the interface list given in the
interfaces parameter. This restricts the networks that smbd will serve, to packets
coming in on those interfaces. Note that you should not use this parameter for
machines that are serving PPP or other intermittent or non-broadcast network
interfaces as it will not cope with non-permanent interfaces.
If bind interfaces only is set and the network address 127.0.0.1 is not added to the
interfaces parameter list smbpasswd(8) may not work as expected due to the reasons
covered below.
To change a users SMB password, the smbpasswd by default connects to the localhost -
127.0.0.1 address as an SMB client to issue the password change request. If bind
interfaces only is set then unless the network address 127.0.0.1 is added to the
interfaces parameter list then smbpasswd will fail to connect in it's default mode.
smbpasswd can be forced to use the primary IP interface of the local host by using its
smbpasswd(8) -r remote machine parameter, with remote machine set to the IP name of
the primary interface of the local host.
Default: bind interfaces only = no
blocking locks (S)
This parameter controls the behavior of smbd(8) when given a request by a client to
obtain a byte range lock on a region of an open file, and the request has a time limit
associated with it.
If this parameter is set and the lock range requested cannot be immediately satisfied,
samba will internally queue the lock request, and periodically attempt to obtain the
lock until the timeout period expires.
If this parameter is set to no, then samba will behave as previous versions of Samba
would and will fail the lock request immediately if the lock range cannot be obtained.
Default: blocking locks = yes
block size (S)
This parameter controls the behavior of smbd(8) when reporting disk free sizes. By
default, this reports a disk block size of 1024 bytes.
Changing this parameter may have some effect on the efficiency of client writes, this
is not yet confirmed. This parameter was added to allow advanced administrators to
change it (usually to a higher value) and test the effect it has on client write
performance without re-compiling the code. As this is an experimental option it may be
removed in a future release.
Changing this option does not change the disk free reporting size, just the block size
unit reported to the client.
Default: block size = 1024
Example: block size = 4096
browsable
This parameter is a synonym for browseable.
browseable (S)
This controls whether this share is seen in the list of available shares in a net view
and in the browse list.
Default: browseable = yes
browse list (G)
This controls whether smbd(8) will serve a browse list to a client doing a
NetServerEnum call. Normally set to yes. You should never need to change this.
Default: browse list = yes
cache directory (G)
Usually, most of the TDB files are stored in the lock directory. Since Samba 3.4.0, it
is possible to differentiate between TDB files with persistent data and TDB files with
non-persistent data using the state directory and the cache directory options.
This option specifies the directory for storing TDB files containing non-persistent
data that will be kept across service restarts. The directory should be placed on
persistent storage, but the data can be safely deleted by an administrator.
Default: cache directory = /var/cache/samba
Example: cache directory = /var/run/samba/locks/cache
casesignames
This parameter is a synonym for case sensitive.
case sensitive (S)
See the discussion in the section name mangling.
Default: case sensitive = auto
change notify (G)
This parameter specifies whether Samba should reply to a client's file change notify
requests.
You should never need to change this parameter
Default: change notify = yes
change share command (G)
Samba 2.2.0 introduced the ability to dynamically add and delete shares via the
Windows NT 4.0 Server Manager. The change share command is used to define an external
program or script which will modify an existing service definition in smb.conf.
In order to successfully execute the change share command, smbd requires that the
administrator connects using a root account (i.e. uid == 0) or has the
SeDiskOperatorPrivilege. Scripts defined in the change share command parameter are
executed as root.
When executed, smbd will automatically invoke the change share command with six
parameters.
• configFile - the location of the global smb.conf file.
• shareName - the name of the new share.
• pathName - path to an **existing** directory on disk.
• comment - comment string to associate with the new share.
• max connections Number of maximum simultaneous connections to this share.
• CSC policy - client side caching policy in string form. Valid values are:
manual, documents, programs, disable.
This parameter is only used to modify existing file share definitions. To modify
printer shares, use the "Printers..." folder as seen when browsing the Samba host.
Default: change share command =
Example: change share command = /usr/local/bin/changeshare
check parent directory delete on close (S)
A Windows SMB server prevents the client from creating files in a directory that has
the delete-on-close flag set. By default Samba doesn't perform this check as this
check is a quite expensive operation in Samba.
Default: check parent directory delete on close = no
check password script (G)
The name of a program that can be used to check password complexity. The password is
sent to the program's standard input.
The program must return 0 on a good password, or any other value if the password is
bad. In case the password is considered weak (the program does not return 0) the user
will be notified and the password change will fail.
In Samba AD, this script will be run AS ROOT by samba(8) without any substitutions.
Note that starting with Samba 4.11 the following environment variables are exported to
the script:
• SAMBA_CPS_ACCOUNT_NAME is always present and contains the sAMAccountName of
user, the is the same as the %u substitutions in the none AD DC case.
• SAMBA_CPS_USER_PRINCIPAL_NAME is optional in the AD DC case if the
userPrincipalName is present.
• SAMBA_CPS_FULL_NAME is optional if the displayName is present.
Note: In the example directory is a sample program called crackcheck that uses
cracklib to check the password quality.
Default: check password script = # Disabled
Example: check password script = /usr/local/sbin/crackcheck
cldap port (G)
This option controls the port used by the CLDAP protocol.
Default: cldap port = 389
Example: cldap port = 3389
client ipc max protocol (G)
The value of the parameter (a string) is the highest protocol level that will be
supported for IPC$ connections as DCERPC transport.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol.
The value default refers to the latest supported protocol, currently SMB3_11.
See client max protocol for a full list of available protocols. The values CORE,
COREPLUS, LANMAN1, LANMAN2 are silently upgraded to NT1.
Default: client ipc max protocol = default
Example: client ipc max protocol = SMB2_10
client ipc min protocol (G)
This setting controls the minimum protocol version that the will be attempted to use
for IPC$ connections as DCERPC transport.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol.
The value default refers to the higher value of NT1 and the effective value of client
min protocol.
See client max protocol for a full list of available protocols. The values CORE,
COREPLUS, LANMAN1, LANMAN2 are silently upgraded to NT1.
Default: client ipc min protocol = default
Example: client ipc min protocol = SMB3_11
client ipc signing (G)
This controls whether the client is allowed or required to use SMB signing for IPC$
connections as DCERPC transport. Possible values are desired, required and disabled.
When set to required or default, SMB signing is mandatory.
When set to desired, SMB signing is offered, but not enforced and if set to disabled,
SMB signing is not offered either.
Connections from winbindd to Active Directory Domain Controllers always enforce
signing.
Default: client ipc signing = default
client lanman auth (G)
This parameter has been deprecated since Samba 4.13 and support for LanMan (as
distinct from NTLM, NTLMv2 or Kerberos) authentication as a client will be removed in
a future Samba release.
That is, in the future, the current default of client NTLMv2 auth = yes will be the
enforced behaviour.
This parameter determines whether or not smbclient(8) and other samba client tools
will attempt to authenticate itself to servers using the weaker LANMAN password hash.
If disabled, only server which support NT password hashes (e.g. Windows NT/2000,
Samba, etc... but not Windows 95/98) will be able to be connected from the Samba
client.
The LANMAN encrypted response is easily broken, due to its case-insensitive nature,
and the choice of algorithm. Clients without Windows 95/98 servers are advised to
disable this option.
Disabling this option will also disable the client plaintext auth option.
Likewise, if the client ntlmv2 auth parameter is enabled, then only NTLMv2 logins will
be attempted.
Default: client lanman auth = no
client ldap sasl wrapping (G)
The client ldap sasl wrapping defines whether ldap traffic will be signed or signed
and encrypted (sealed). Possible values are plain, sign and seal.
The values sign and seal are only available if Samba has been compiled against a
modern OpenLDAP version (2.3.x or higher).
This option is needed firstly to secure the privacy of administrative connections from
samba-tool, including in particular new or reset passwords for users. For this reason
the default is seal.
Additionally, winbindd and the net tool can use LDAP to communicate with Domain
Controllers, so this option also controls the level of privacy for those connections.
All supported AD DC versions will enforce the usage of at least signed LDAP
connections by default, so a value of at least sign is required in practice.
The default value is seal. That implies synchronizing the time with the KDC in the
case of using Kerberos.
Default: client ldap sasl wrapping = seal
client max protocol (G)
The value of the parameter (a string) is the highest protocol level that will be
supported by the client.
Possible values are :
• CORE: Earliest version. No concept of user names.
• COREPLUS: Slight improvements on CORE for efficiency.
• LANMAN1: First modern version of the protocol. Long filename support.
• LANMAN2: Updates to Lanman1 protocol.
• NT1: Current up to date version of the protocol. Used by Windows NT. Known
as CIFS.
• SMB2: Re-implementation of the SMB protocol. Used by Windows Vista and
later versions of Windows. SMB2 has sub protocols available.
• SMB2_02: The earliest SMB2 version.
• SMB2_10: Windows 7 SMB2 version.
By default SMB2 selects the SMB2_10 variant.
• SMB3: The same as SMB2. Used by Windows 8. SMB3 has sub protocols
available.
• SMB3_00: Windows 8 SMB3 version.
• SMB3_02: Windows 8.1 SMB3 version.
• SMB3_11: Windows 10 SMB3 version.
By default SMB3 selects the SMB3_11 variant.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol.
The value default refers to SMB3_11.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the client ipc max
protocol option.
Default: client max protocol = default
Example: client max protocol = LANMAN1
client min protocol (G)
This setting controls the minimum protocol version that the client will attempt to
use.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol unless you connect to a
legacy SMB1-only server.
See Related command: client max protocol for a full list of available protocols.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the client ipc min
protocol option.
Note that most command line tools support --option='client min protocol=NT1', so it
may not be required to enable SMB1 protocols globally in smb.conf.
Default: client min protocol = SMB2_02
Example: client min protocol = NT1
client NTLMv2 auth (G)
This parameter has been deprecated since Samba 4.13 and support for NTLM and LanMan
(as distinct from NTLMv2 or Kerberos authentication) will be removed in a future Samba
release.
That is, in the future, the current default of client NTLMv2 auth = yes will be the
enforced behaviour.
This parameter determines whether or not smbclient(8) will attempt to authenticate
itself to servers using the NTLMv2 encrypted password response.
If enabled, only an NTLMv2 and LMv2 response (both much more secure than earlier
versions) will be sent. Older servers (including NT4 < SP4, Win9x and Samba 2.2) are
not compatible with NTLMv2 when not in an NTLMv2 supporting domain
Similarly, if enabled, NTLMv1, client lanman auth and client plaintext auth
authentication will be disabled. This also disables share-level authentication.
If disabled, an NTLM response (and possibly a LANMAN response) will be sent by the
client, depending on the value of client lanman auth.
Note that Windows Vista and later versions already use NTLMv2 by default, and some
sites (particularly those following 'best practice' security polices) only allow
NTLMv2 responses, and not the weaker LM or NTLM.
When client use spnego is also set to yes extended security (SPNEGO) is required in
order to use NTLMv2 only within NTLMSSP. This behavior was introduced with the patches
for CVE-2016-2111.
Default: client NTLMv2 auth = yes
client plaintext auth (G)
This parameter has been deprecated since Samba 4.13 and support for plaintext (as
distinct from NTLM, NTLMv2 or Kerberos authentication) will be removed in a future
Samba release.
That is, in the future, the current default of client plaintext auth = no will be the
enforced behaviour.
Specifies whether a client should send a plaintext password if the server does not
support encrypted passwords.
Default: client plaintext auth = no
client protection (G)
This parameter defines which protection Samba client tools should use by default.
Possible client settings are:
• default - Use the individual default values of the options:
• client signing
• client smb encrypt
• plain - This will send everything just as plaintext, signing or encryption
are turned off.
• sign - This will enable integrity checking.
• encrypt - This will enable integrity checks and force encryption for
privacy.
Default: client protection = default
client schannel (G)
This option is deprecated with Samba 4.8 and will be removed in future. At the same
time the default changed to yes, which will be the hardcoded behavior in future.
This controls whether the client offers or even demands the use of the netlogon
schannel. client schannel = no does not offer the schannel, client schannel = auto
offers the schannel but does not enforce it, and client schannel = yes denies access
if the server is not able to speak netlogon schannel.
Note that for active directory domains this is hardcoded to client schannel = yes.
This option is over-ridden by the require strong key option.
Default: client schannel = yes
Example: client schannel = auto
client signing (G)
This controls whether the client is allowed or required to use SMB signing. Possible
values are desired, required and disabled.
When set to desired or default, SMB signing is offered, but not enforced.
When set to required, SMB signing is mandatory and if set to disabled, SMB signing is
not offered either.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the client ipc signing
option.
Default: client signing = default
client smb encrypt (G)
This parameter controls whether a client should try or is required to use SMB
encryption. It has different effects depending on whether the connection uses SMB1 or
SMB3:
• If the connection uses SMB1, then this option controls the use of a
Samba-specific extension to the SMB protocol introduced in Samba 3.2 that
makes use of the Unix extensions.
• If the connection uses SMB2 or newer, then this option controls the use of
the SMB-level encryption that is supported in SMB version 3.0 and above and
available in Windows 8 and newer.
This parameter can be set globally. Possible values are off, if_required, desired, and
required. A special value is default which is the implicit default setting of
if_required.
Effects for SMB1
The Samba-specific encryption of SMB1 connections is an extension to the SMB
protocol negotiated as part of the UNIX extensions. SMB encryption uses the GSSAPI
(SSPI on Windows) ability to encrypt and sign every request/response in a SMB
protocol stream. When enabled it provides a secure method of SMB/CIFS
communication, similar to an ssh protected session, but using SMB/CIFS
authentication to negotiate encryption and signing keys. Currently this is only
supported smbclient of by Samba 3.2 and newer. Windows does not support this
feature.
When set to default, SMB encryption is probed, but not enforced. When set to
required, SMB encryption is required and if set to disabled, SMB encryption can
not be negotiated.
Effects for SMB3 and newer
Native SMB transport encryption is available in SMB version 3.0 or newer. It is
only used by Samba if client max protocol is set to SMB3 or newer.
These features can be controlled with settings of client smb encrypt as follows:
• Leaving it as default, explicitly setting default, or setting it to
if_required globally will enable negotiation of encryption but will not
turn on data encryption globally.
• Setting it to desired globally will enable negotiation and will turn on
data encryption on sessions and share connections for those servers
that support it.
• Setting it to required globally will enable negotiation and turn on
data encryption on sessions and share connections. Clients that do not
support encryption will be denied access to the server.
• Setting it to off globally will completely disable the encryption
feature for all connections.
Default: client smb encrypt = default
client smb3 encryption algorithms (G)
This parameter specifies the availability and order of encryption algorithms which are
available for negotiation in the SMB3_11 dialect.
It is also possible to remove individual algorithms from the default list, by
prefixing them with '-'. This can avoid having to specify a hardcoded list.
Note: that the removal of AES-128-CCM from the list will result in SMB3_00 and SMB3_02
being unavailable, as it is the default and only available algorithm for these
dialects.
Default: client smb3 encryption algorithms = AES-128-GCM, AES-128-CCM, AES-256-GCM,
AES-256-CCM
Example: client smb3 encryption algorithms = AES-256-GCM
Example: client smb3 encryption algorithms = -AES-128-GCM -AES-128-CCM
client smb3 signing algorithms (G)
This parameter specifies the availability and order of signing algorithms which are
available for negotiation in the SMB3_11 dialect.
It is also possible to remove individual algorithms from the default list, by
prefixing them with '-'. This can avoid having to specify a hardcoded list.
Note: that the removal of AES-128-CMAC from the list will result in SMB3_00 and
SMB3_02 being unavailable, and the removal of HMAC-SHA256 will result in SMB2_02 and
SMB2_10 being unavailable, as these are the default and only available algorithms for
these dialects.
Default: client smb3 signing algorithms = AES-128-GMAC, AES-128-CMAC, HMAC-SHA256
Example: client smb3 signing algorithms = AES-128-CMAC, HMAC-SHA256
Example: client smb3 signing algorithms = -AES-128-CMAC
client use kerberos (G)
This parameter determines whether Samba client tools will try to authenticate using
Kerberos. For Kerberos authentication you need to use dns names instead of IP
addresses when connecting to a service.
Possible option settings are:
• desired - Kerberos authentication will be tried first and if it fails it
automatically fallback to NTLM.
• required - Kerberos authentication will be required. There will be no
fallback to NTLM or a different alternative.
• off - Don't use Kerberos, use NTLM instead or another alternative.
In case that weak cryptography is not allowed (e.g. FIPS mode) the default will be
forced to required.
Default: client use kerberos = desired
client use spnego principal (G)
This parameter determines whether or not smbclient(8) and other samba components
acting as a client will attempt to use the server-supplied principal sometimes given
in the SPNEGO exchange.
If enabled, Samba can attempt to use Kerberos to contact servers known only by IP
address. Kerberos relies on names, so ordinarily cannot function in this situation.
This is a VERY BAD IDEA for security reasons, and so this parameter SHOULD NOT BE
USED. It will be removed in a future version of Samba.
If disabled, Samba will use the name used to look up the server when asking the KDC
for a ticket. This avoids situations where a server may impersonate another,
soliciting authentication as one principal while being known on the network as
another.
Note that Windows XP SP2 and later versions already follow this behaviour, and Windows
Vista and later servers no longer supply this 'rfc4178 hint' principal on the server
side.
This parameter is deprecated in Samba 4.2.1 and will be removed (along with the
functionality) in a later release of Samba.
Default: client use spnego principal = no
client use spnego (G)
This parameter has been deprecated since Samba 4.13 and support for NTLMv2, NTLM and
LanMan authentication outside NTLMSSP will be removed in a future Samba release.
That is, in the future, the current default of client use spnego = yes will be the
enforced behaviour.
This variable controls whether Samba clients will try to use Simple and Protected
NEGOtiation (as specified by rfc2478) with supporting servers (including WindowsXP,
Windows2000 and Samba 3.0) to agree upon an authentication mechanism. This enables
Kerberos authentication in particular.
When client NTLMv2 auth is also set to yes extended security (SPNEGO) is required in
order to use NTLMv2 only within NTLMSSP. This behavior was introduced with the patches
for CVE-2016-2111.
Default: client use spnego = yes
cluster addresses (G)
With this parameter you can add additional addresses that nmbd will register with a
WINS server. Similarly, these addresses will be registered by default when net ads dns
register is called with clustering = yes configured.
Default: cluster addresses =
Example: cluster addresses = 10.0.0.1 10.0.0.2 10.0.0.3
clustering (G)
This parameter specifies whether Samba should contact ctdb for accessing its tdb files
and use ctdb as a backend for its messaging backend.
Set this parameter to yes only if you have a cluster setup with ctdb running.
Default: clustering = no
comment (S)
This is a text field that is seen next to a share when a client does a queries the
server, either via the network neighborhood or via net view to list what shares are
available.
If you want to set the string that is displayed next to the machine name then see the
server string parameter.
Default: comment = # No comment
Example: comment = Fred's Files
config backend (G)
This controls the backend for storing the configuration. Possible values are file (the
default) and registry. When config backend = registry is encountered while loading
smb.conf, the configuration read so far is dropped and the global options are read
from registry instead. So this triggers a registry only configuration. Share
definitions are not read immediately but instead registry shares is set to yes.
Note: This option can not be set inside the registry configuration itself.
Default: config backend = file
Example: config backend = registry
config file (G)
This allows you to override the config file to use, instead of the default (usually
smb.conf). There is a chicken and egg problem here as this option is set in the config
file!
For this reason, if the name of the config file has changed when the parameters are
loaded then it will reload them from the new config file.
This option takes the usual substitutions, which can be very useful.
If the config file doesn't exist then it won't be loaded (allowing you to special case
the config files of just a few clients).
No default
Example: config file = /usr/local/samba/lib/smb.conf.%m
copy (S)
This parameter allows you to "clone" service entries. The specified service is simply
duplicated under the current service's name. Any parameters specified in the current
section will override those in the section being copied.
This feature lets you set up a 'template' service and create similar services easily.
Note that the service being copied must occur earlier in the configuration file than
the service doing the copying.
Default: copy =
Example: copy = otherservice
create krb5 conf (G)
Setting this parameter to no prevents winbind from creating custom krb5.conf files.
Winbind normally does this because the krb5 libraries are not AD-site-aware and thus
would pick any domain controller out of potentially very many. Winbind is site-aware
and makes the krb5 libraries use a local DC by creating its own krb5.conf files.
Preventing winbind from doing this might become necessary if you have to add special
options into your system-krb5.conf that winbind does not see.
Default: create krb5 conf = yes
create mode
This parameter is a synonym for create mask.
create mask (S)
When a file is created, the necessary permissions are calculated according to the
mapping from DOS modes to UNIX permissions, and the resulting UNIX mode is then
bit-wise 'AND'ed with this parameter. This parameter may be thought of as a bit-wise
MASK for the UNIX modes of a file. Any bit not set here will be removed from the modes
set on a file when it is created.
The default value of this parameter removes the group and other write and execute bits
from the UNIX modes.
Following this Samba will bit-wise 'OR' the UNIX mode created from this parameter with
the value of the force create mode parameter which is set to 000 by default.
This parameter does not affect directory masks. See the parameter directory mask for
details.
Default: create mask = 0744
Example: create mask = 0775
csc policy (S)
This stands for client-side caching policy, and specifies how clients capable of
offline caching will cache the files in the share. The valid values are: manual,
documents, programs, disable.
These values correspond to those used on Windows servers.
For example, shares containing roaming profiles can have offline caching disabled
using csc policy = disable.
Default: csc policy = manual
Example: csc policy = programs
ctdbd socket (G)
If you set clustering=yes, you need to tell Samba where ctdbd listens on its unix
domain socket. The default path as of ctdb 1.0 is /tmp/ctdb.socket which you have to
explicitly set for Samba in smb.conf.
Default: ctdbd socket =
Example: ctdbd socket = /tmp/ctdb.socket
ctdb locktime warn threshold (G)
In a cluster environment using Samba and ctdb it is critical that locks on central
ctdb-hosted databases like locking.tdb are not held for long. With the current Samba
architecture it happens that Samba takes a lock and while holding that lock makes file
system calls into the shared cluster file system. This option makes Samba warn if it
detects that it has held locks for the specified number of milliseconds. If this
happens, smbd will emit a debug level 0 message into its logs and potentially into
syslog. The most likely reason for such a log message is that an operation of the
cluster file system Samba exports is taking longer than expected. The messages are
meant as a debugging aid for potential cluster problems.
The default value of 0 disables this logging.
Default: ctdb locktime warn threshold = 0
ctdb timeout (G)
This parameter specifies a timeout in milliseconds for the connection between Samba
and ctdb. It is only valid if you have compiled Samba with clustering and if you have
set clustering=yes.
When something in the cluster blocks, it can happen that we wait indefinitely long for
ctdb, just adding to the blocking condition. In a well-running cluster this should
never happen, but there are too many components in a cluster that might have hickups.
Choosing the right balance for this value is very tricky, because on a busy cluster
long service times to transfer something across the cluster might be valid. Setting it
too short will degrade the service your cluster presents, setting it too long might
make the cluster itself not recover from something severely broken for too long.
Be aware that if you set this parameter, this needs to be in the file smb.conf, it is
not really helpful to put this into a registry configuration (typical on a cluster),
because to access the registry contact to ctdb is required.
Setting ctdb timeout to n makes any process waiting longer than n milliseconds for a
reply by the cluster panic. Setting it to 0 (the default) makes Samba block forever,
which is the highly recommended default.
Default: ctdb timeout = 0
cups connection timeout (G)
This parameter is only applicable if printing is set to cups.
If set, this option specifies the number of seconds that smbd will wait whilst trying
to contact to the CUPS server. The connection will fail if it takes longer than this
number of seconds.
Default: cups connection timeout = 30
Example: cups connection timeout = 60
cups encrypt (G)
This parameter is only applicable if printing is set to cups and if you use CUPS newer
than 1.0.x.It is used to define whether or not Samba should use encryption when
talking to the CUPS server. Possible values are auto, yes and no
When set to auto we will try to do a TLS handshake on each CUPS connection setup. If
that fails, we will fall back to unencrypted operation.
Default: cups encrypt = no
cups options (S)
This parameter is only applicable if printing is set to cups. Its value is a free form
string of options passed directly to the cups library.
You can pass any generic print option known to CUPS (as listed in the CUPS "Software
Users' Manual"). You can also pass any printer specific option (as listed in
"lpoptions -d printername -l") valid for the target queue. Multiple parameters should
be space-delimited name/value pairs according to the PAPI text option ABNF
specification. Collection values ("name={a=... b=... c=...}") are stored with the
curley brackets intact.
You should set this parameter to raw if your CUPS server error_log file contains
messages such as "Unsupported format 'application/octet-stream'" when printing from a
Windows client through Samba. It is no longer necessary to enable system wide raw
printing in /etc/cups/mime.{convs,types}.
Default: cups options = ""
Example: cups options = "raw media=a4"
cups server (G)
This parameter is only applicable if printing is set to cups.
If set, this option overrides the ServerName option in the CUPS client.conf. This is
necessary if you have virtual samba servers that connect to different CUPS daemons.
Optionally, a port can be specified by separating the server name and port number with
a colon. If no port was specified, the default port for IPP (631) will be used.
Default: cups server = ""
Example: cups server = mycupsserver
Example: cups server = mycupsserver:1631
dcerpc endpoint servers (G)
Specifies which DCE/RPC endpoint servers should be run.
Default: dcerpc endpoint servers = epmapper, wkssvc, samr, netlogon, lsarpc, drsuapi,
dssetup, unixinfo, browser, eventlog6, backupkey, dnsserver
Example: dcerpc endpoint servers = rpcecho
deadtime (G)
The value of the parameter (a decimal integer) represents the number of minutes of
inactivity before a connection is considered dead, and it is disconnected. The
deadtime only takes effect if the number of open files is zero.
This is useful to stop a server's resources being exhausted by a large number of
inactive connections.
Most clients have an auto-reconnect feature when a connection is broken so in most
cases this parameter should be transparent to users.
Using this parameter with a timeout of a few minutes is recommended for most systems.
A deadtime of zero indicates that no auto-disconnection should be performed.
Default: deadtime = 10080
Example: deadtime = 15
debug class (G)
With this boolean parameter enabled, the debug class (DBGC_CLASS) will be displayed in
the debug header.
For more information about currently available debug classes, see section about log
level.
Default: debug class = no
debug encryption (G)
This option will make the smbd server and client code using libsmb (smbclient, smbget,
smbspool, ...) dump the Session Id, the decrypted Session Key, the Signing Key, the
Application Key, the Encryption Key and the Decryption Key every time an SMB3+ session
is established. This information will be printed in logs at level 0.
Warning: access to these values enables the decryption of any encrypted traffic on the
dumped sessions. This option should only be enabled for debugging purposes.
Default: debug encryption = no
debug hires timestamp (G)
Sometimes the timestamps in the log messages are needed with a resolution of higher
that seconds, this boolean parameter adds microsecond resolution to the timestamp
message header when turned on.
Note that the parameter debug timestamp or debug syslog format must be on for this to
have an effect.
Default: debug hires timestamp = yes
debug pid (G)
When using only one log file for more then one forked smbd(8)-process there may be
hard to follow which process outputs which message. This boolean parameter is adds the
process-id to the timestamp message headers in the logfile when turned on.
Note that the parameter debug timestamp must be on for this to have an effect.
Default: debug pid = no
debug prefix timestamp (G)
With this option enabled, the timestamp message header is prefixed to the debug
message without the filename and function information that is included with the debug
timestamp parameter. This gives timestamps to the messages without adding an
additional line.
Note that this parameter overrides the debug timestamp parameter.
Default: debug prefix timestamp = no
debug syslog format (G)
With this option enabled (yes (alias in_logs) or always), debug messages are printed
in a single-line format like that traditionally produced by syslog. The timestamp
consists of an abbreviated month, space-padded date, and time including seconds. This
is followed by the hostname and the program name, with the process-ID in square
brackets.
The value always produces this log format even to STDOUT or STDERR
The value no defers to other parameters and typically produces traditional two-line
Samba logs to log files.
If debug hires timestamp is also enabled then an RFC5424 timestamp is used instead.
Default: debug syslog format = no
winbind debug traceid (G)
With this boolean parameter enabled, the per request unique traceid will be displayed
in the debug header for winbind processes.
Default: winbind debug traceid = no
debug uid (G)
Samba is sometimes run as root and sometime run as the connected user, this boolean
parameter inserts the current euid, egid, uid and gid to the timestamp message headers
in the log file if turned on.
Note that the parameter debug timestamp must be on for this to have an effect.
Default: debug uid = no
dedicated keytab file (G)
Specifies the absolute path to the kerberos keytab file when kerberos method is set to
"dedicated keytab".
Default: dedicated keytab file =
Example: dedicated keytab file = /usr/local/etc/krb5.keytab
default case (S)
See the section on name mangling. Also note the short preserve case parameter.
Default: default case = lower
default devmode (S)
This parameter is only applicable to printable services. When smbd is serving Printer
Drivers to Windows NT/2k/XP clients, each printer on the Samba server has a Device
Mode which defines things such as paper size and orientation and duplex settings. The
device mode can only correctly be generated by the printer driver itself (which can
only be executed on a Win32 platform). Because smbd is unable to execute the driver
code to generate the device mode, the default behavior is to set this field to NULL.
Most problems with serving printer drivers to Windows NT/2k/XP clients can be traced
to a problem with the generated device mode. Certain drivers will do things such as
crashing the client's Explorer.exe with a NULL devmode. However, other printer drivers
can cause the client's spooler service (spoolsv.exe) to die if the devmode was not
created by the driver itself (i.e. smbd generates a default devmode).
This parameter should be used with care and tested with the printer driver in
question. It is better to leave the device mode to NULL and let the Windows client set
the correct values. Because drivers do not do this all the time, setting default
devmode = yes will instruct smbd to generate a default one.
For more information on Windows NT/2k printing and Device Modes, see the MSDN
documentation.
Default: default devmode = yes
default
This parameter is a synonym for default service.
default service (G)
This parameter specifies the name of a service which will be connected to if the
service actually requested cannot be found. Note that the square brackets are NOT
given in the parameter value (see example below).
There is no default value for this parameter. If this parameter is not given,
attempting to connect to a nonexistent service results in an error.
Typically the default service would be a guest ok, read only service.
Also note that the apparent service name will be changed to equal that of the
requested service, this is very useful as it allows you to use macros like %S to make
a wildcard service.
Note also that any "_" characters in the name of the service used in the default
service will get mapped to a "/". This allows for interesting things.
Default: default service =
Example: default service = pub
defer sharing violations (G)
Windows allows specifying how a file will be shared with other processes when it is
opened. Sharing violations occur when a file is opened by a different process using
options that violate the share settings specified by other processes. This parameter
causes smbd to act as a Windows server does, and defer returning a "sharing violation"
error message for up to one second, allowing the client to close the file causing the
violation in the meantime.
UNIX by default does not have this behaviour.
There should be no reason to turn off this parameter, as it is designed to enable
Samba to more correctly emulate Windows.
Default: defer sharing violations = yes
delete group script (G)
This is the full pathname to a script that will be run AS ROOT by smbd(8) when a group
is requested to be deleted. It will expand any %g to the group name passed. This
script is only useful for installations using the Windows NT domain administration
tools.
Default: delete group script =
deleteprinter command (G)
With the introduction of MS-RPC based printer support for Windows NT/2000 clients in
Samba 2.2, it is now possible to delete a printer at run time by issuing the
DeletePrinter() RPC call.
For a Samba host this means that the printer must be physically deleted from the
underlying printing system. The deleteprinter command defines a script to be run which
will perform the necessary operations for removing the printer from the print system
and from smb.conf.
The deleteprinter command is automatically called with only one parameter: printer
name.
Once the deleteprinter command has been executed, smbd will reparse the smb.conf to
check that the associated printer no longer exists. If the sharename is still valid,
then smbd will return an ACCESS_DENIED error to the client.
Default: deleteprinter command =
Example: deleteprinter command = /usr/bin/removeprinter
delete readonly (S)
This parameter allows readonly files to be deleted. This is not normal DOS semantics,
but is allowed by UNIX.
This option may be useful for running applications such as rcs, where UNIX file
ownership prevents changing file permissions, and DOS semantics prevent deletion of a
read only file.
Default: delete readonly = no
delete share command (G)
Samba 2.2.0 introduced the ability to dynamically add and delete shares via the
Windows NT 4.0 Server Manager. The delete share command is used to define an external
program or script which will remove an existing service definition from smb.conf.
In order to successfully execute the delete share command, smbd requires that the
administrator connects using a root account (i.e. uid == 0) or has the
SeDiskOperatorPrivilege. Scripts defined in the delete share command parameter are
executed as root.
When executed, smbd will automatically invoke the delete share command with two
parameters.
• configFile - the location of the global smb.conf file.
• shareName - the name of the existing service.
This parameter is only used to remove file shares. To delete printer shares, see the
deleteprinter command.
Default: delete share command =
Example: delete share command = /usr/local/bin/delshare
delete user from group script (G)
Full path to the script that will be called when a user is removed from a group using
the Windows NT domain administration tools. It will be run by smbd(8) AS ROOT. Any %g
will be replaced with the group name and any %u will be replaced with the user name.
Default: delete user from group script =
Example: delete user from group script = /usr/sbin/deluser %u %g
delete user script (G)
This is the full pathname to a script that will be run by smbd(8) when managing users
with remote RPC (NT) tools.
This script is called when a remote client removes a user from the server, normally
using 'User Manager for Domains' or rpcclient.
This script should delete the given UNIX username.
Default: delete user script =
Example: delete user script = /usr/local/samba/bin/del_user %u
delete veto files (S)
This option is used when Samba is attempting to delete a directory that contains one
or more vetoed files or directories or non-visible files or directories (such as
dangling symlinks that point nowhere). (see the veto files, hide special files, hide
unreadable, hide unwriteable files options). If this option is set to no (the default)
then if a vetoed directory contains any non-vetoed files or directories then the
directory delete will fail. This is usually what you want.
If this option is set to yes, then Samba will attempt to recursively delete any files
and directories within the vetoed directory. This can be useful for integration with
file serving systems such as NetAtalk which create meta-files within directories you
might normally veto DOS/Windows users from seeing (e.g. .AppleDouble)
Setting delete veto files = yes allows these directories to be transparently deleted
when the parent directory is deleted (so long as the user has permissions to do so).
Default: delete veto files = no
dfree cache time (S)
The dfree cache time should only be used on systems where a problem occurs with the
internal disk space calculations. This has been known to happen with Ultrix, but may
occur with other operating systems. The symptom that was seen was an error of "Abort
Retry Ignore" at the end of each directory listing.
This is a new parameter introduced in Samba version 3.0.21. It specifies in seconds
the time that smbd will cache the output of a disk free query. If set to zero (the
default) no caching is done. This allows a heavily loaded server to prevent rapid
spawning of dfree command scripts increasing the load.
By default this parameter is zero, meaning no caching will be done.
No default
Example: dfree cache time = 60
dfree command (S)
The dfree command setting should only be used on systems where a problem occurs with
the internal disk space calculations. This has been known to happen with Ultrix, but
may occur with other operating systems. The symptom that was seen was an error of
"Abort Retry Ignore" at the end of each directory listing.
This setting allows the replacement of the internal routines to calculate the total
disk space and amount available with an external routine. The example below gives a
possible script that might fulfill this function.
In Samba version 3.0.21 this parameter has been changed to be a per-share parameter,
and in addition the parameter dfree cache time was added to allow the output of this
script to be cached for systems under heavy load.
The external program will be passed a single parameter indicating a directory in the
filesystem being queried. This will typically consist of the string ./. The script
should return two integers in ASCII. The first should be the total disk space in
blocks, and the second should be the number of available blocks. An optional third
return value can give the block size in bytes. The default blocksize is 1024 bytes.
Note: Your script should NOT be setuid or setgid and should be owned by (and writeable
only by) root!
Where the script dfree (which must be made executable) could be:
#!/bin/sh
df "$1" | tail -1 | awk '{print $(NF-4),$(NF-2)}'
or perhaps (on Sys V based systems):
#!/bin/sh
/usr/bin/df -k "$1" | tail -1 | awk '{print $3" "$5}'
Note that you may have to replace the command names with full path names on some
systems. Also note the arguments passed into the script should be quoted inside the
script in case they contain special characters such as spaces or newlines.
By default internal routines for determining the disk capacity and remaining space
will be used.
No default
Example: dfree command = /usr/local/samba/bin/dfree
dgram port (G)
Specifies which ports the server should listen on for NetBIOS datagram traffic.
Default: dgram port = 138
directory mode
This parameter is a synonym for directory mask.
directory mask (S)
This parameter is the octal modes which are used when converting DOS modes to UNIX
modes when creating UNIX directories.
When a directory is created, the necessary permissions are calculated according to the
mapping from DOS modes to UNIX permissions, and the resulting UNIX mode is then
bit-wise 'AND'ed with this parameter. This parameter may be thought of as a bit-wise
MASK for the UNIX modes of a directory. Any bit not set here will be removed from the
modes set on a directory when it is created.
The default value of this parameter removes the 'group' and 'other' write bits from
the UNIX mode, allowing only the user who owns the directory to modify it.
Following this Samba will bit-wise 'OR' the UNIX mode created from this parameter with
the value of the force directory mode parameter. This parameter is set to 000 by
default (i.e. no extra mode bits are added).
Default: directory mask = 0755
Example: directory mask = 0775
directory security mask (S)
This parameter has been removed for Samba 4.0.0.
No default
disable netbios (G)
Enabling this parameter will disable netbios support in Samba. Netbios is the only
available form of browsing in Windows versions prior to Windows 2000.
Note
Clients that only support netbios won't be able to see your samba server when
netbios support is disabled.
Default: disable netbios = no
disable spoolss (G)
Enabling this parameter will disable Samba's support for the SPOOLSS set of MS-RPC's
and will yield identical behavior as Samba 2.0.x. Windows NT/2000 clients will
downgrade to using Lanman style printing commands. Windows 9x/ME will be unaffected by
the parameter. However, this will also disable the ability to upload printer drivers
to a Samba server via the Windows NT Add Printer Wizard or by using the NT printer
properties dialog window. It will also disable the capability of Windows NT/2000
clients to download print drivers from the Samba host upon demand. Be very careful
about enabling this parameter.
Default: disable spoolss = no
dmapi support (S)
This parameter specifies whether Samba should use DMAPI to determine whether a file is
offline or not. This would typically be used in conjunction with a hierarchical
storage system that automatically migrates files to tape.
Note that Samba infers the status of a file by examining the events that a DMAPI
application has registered interest in. This heuristic is satisfactory for a number of
hierarchical storage systems, but there may be system for which it will fail. In this
case, Samba may erroneously report files to be offline.
This parameter is only available if a supported DMAPI implementation was found at
compilation time. It will only be used if DMAPI is found to enabled on the system at
run time.
Default: dmapi support = no
dns forwarder (G)
This option specifies the list of DNS servers that DNS requests will be forwarded to
if they can not be handled by Samba itself.
The DNS forwarder is only used if the internal DNS server in Samba is used. Port
numbers can be appended by separating them from the address by using a colon (':').
When specifying a port, IPv6 addresses must be enclosed in square brackets ('[' and
']'). IPv6 forwarder addresses with no port specified, don't need the square brackets,
and default to port 53.
Default: dns forwarder =
Example: dns forwarder = 192.168.0.1 192.168.0.2 ::1 [2001:db8::1]
[2001:db8:1:2::1]:54
dns port (G)
Specifies which ports the server should listen on for DNS traffic.
It makes possible to use another DNS server as a front and forward to Samba.
Warning
Dynamic DNS updates may not be proxied by the front DNS server when forwarding to
Samba. Dynamic DNS update proxying depends on the features of the other DNS server
used as a front.
Default: dns port = 53
dns proxy (G)
Specifies that nmbd(8) when acting as a WINS server and finding that a NetBIOS name
has not been registered, should treat the NetBIOS name word-for-word as a DNS name and
do a lookup with the DNS server for that name on behalf of the name-querying client.
Note that the maximum length for a NetBIOS name is 15 characters, so the DNS name (or
DNS alias) can likewise only be 15 characters, maximum.
nmbd spawns a second copy of itself to do the DNS name lookup requests, as doing a
name lookup is a blocking action.
Default: dns proxy = yes
dns update command (G)
This option sets the command that is called when there are DNS updates. It should
update the local machines DNS names using TSIG-GSS.
Default: dns update command = /usr/sbin/samba_dnsupdate
Example: dns update command = /usr/local/sbin/dnsupdate
dns zone scavenging (G)
When enabled (the default is disabled) unused dynamic dns records are periodically
removed.
Warning
This option should not be enabled for installations created with versions of samba
before 4.9. Doing this will result in the loss of static DNS entries. This is due
to a bug in previous versions of samba (BUG 12451) which marked dynamic DNS
records as static and static records as dynamic.
Note
If one record for a DNS name is static (non-aging) then no other record for that
DNS name will be scavenged.
Default: dns zone scavenging = no
dns zone transfer clients allow (G)
This option specifies the list of IPs authorized to ask for dns zone transfer from
bind DLZ module.
The IP list is comma and space separated and specified in the same syntax as used in
hosts allow, specifically including IP address, IP prefixes and IP address masks.
As this is a DNS server option, hostnames are naturally not permitted.
The default behaviour is to deny any request. A request will be authorized only if the
emitting client is identified in this list, and not in dns zone transfer clients deny
Default: dns zone transfer clients allow =
Example: dns zone transfer clients allow = 192.168.0.1
dns zone transfer clients deny (G)
This option specifies the list of IPs denied to ask for dns zone transfer from bind
DLZ module.
The IP list is comma and space separated and specified in the same syntax as used in
hosts allow, specifically including IP address, IP prefixes and IP address masks.
As this is a DNS server option, hostnames are naturally not permitted.
If a client identified in this list sends a zone transfer request, it will always be
denied, even if they are in dns zone transfer clients allow. This allows the
definition of specific denied clients within an authorized subnet.
Default: dns zone transfer clients deny =
Example: dns zone transfer clients deny = 192.168.0.1
domain logons (G)
This parameter has been deprecated since Samba 4.13 and support for NT4-style domain
logons(as distinct from the Samba AD DC) will be removed in a future Samba release.
That is, in the future, the current default of domain logons = no will be the enforced
behaviour.
If set to yes, the Samba server will provide the netlogon service for Windows 9X
network logons for the workgroup it is in. This will also cause the Samba server to
act as a domain controller for NT4 style domain services. For more details on setting
up this feature see the Domain Control chapter of the Samba HOWTO Collection.
Default: domain logons = no
domain master (G)
Tell smbd(8) to enable WAN-wide browse list collation. Setting this option causes nmbd
to claim a special domain specific NetBIOS name that identifies it as a domain master
browser for its given workgroup. Local master browsers in the same workgroup on
broadcast-isolated subnets will give this nmbd their local browse lists, and then ask
smbd(8) for a complete copy of the browse list for the whole wide area network.
Browser clients will then contact their local master browser, and will receive the
domain-wide browse list, instead of just the list for their broadcast-isolated subnet.
Note that Windows NT Primary Domain Controllers expect to be able to claim this
workgroup specific special NetBIOS name that identifies them as domain master browsers
for that workgroup by default (i.e. there is no way to prevent a Windows NT PDC from
attempting to do this). This means that if this parameter is set and nmbd claims the
special name for a workgroup before a Windows NT PDC is able to do so then cross
subnet browsing will behave strangely and may fail.
If domain logons = yes, then the default behavior is to enable the domain master
parameter. If domain logons is not enabled (the default setting), then neither will
domain master be enabled by default.
When domain logons = Yes the default setting for this parameter is Yes, with the
result that Samba will be a PDC. If domain master = No, Samba will function as a BDC.
In general, this parameter should be set to 'No' only on a BDC.
Default: domain master = auto
dont descend (S)
There are certain directories on some systems (e.g., the /proc tree under Linux) that
are either not of interest to clients or are infinitely deep (recursive). This
parameter allows you to specify a comma-delimited list of directories that the server
should always show as empty.
Note that Samba can be very fussy about the exact format of the "dont descend"
entries. For example you may need ./proc instead of just /proc. Experimentation is the
best policy :-)
Default: dont descend =
Example: dont descend = /proc,/dev
dos charset (G)
DOS SMB clients assume the server has the same charset as they do. This option
specifies which charset Samba should use to talk to DOS clients.
The default depends on which charsets you have installed. Samba tries to use charset
850 but falls back to ASCII in case it is not available. Run testparm(1) to check the
default on your system.
No default
dos filemode (S)
The default behavior in Samba is to provide UNIX-like behavior where only the owner of
a file/directory is able to change the permissions on it. However, this behavior is
often confusing to DOS/Windows users. Enabling this parameter allows a user who has
write access to the file (by whatever means, including an ACL permission) to modify
the permissions (including ACL) on it. Note that a user belonging to the group owning
the file will not be allowed to change permissions if the group is only granted read
access. Ownership of the file/directory may also be changed. Note that using the VFS
modules acl_xattr or acl_tdb which store native Windows as meta-data will
automatically turn this option on for any share for which they are loaded, as they
require this option to emulate Windows ACLs correctly.
Default: dos filemode = no
dos filetime resolution (S)
Under the DOS and Windows FAT filesystem, the finest granularity on time resolution is
two seconds. Setting this parameter for a share causes Samba to round the reported
time down to the nearest two second boundary when a query call that requires one
second resolution is made to smbd(8).
This option is mainly used as a compatibility option for Visual C++ when used against
Samba shares. If oplocks are enabled on a share, Visual C++ uses two different time
reading calls to check if a file has changed since it was last read. One of these
calls uses a one-second granularity, the other uses a two second granularity. As the
two second call rounds any odd second down, then if the file has a timestamp of an odd
number of seconds then the two timestamps will not match and Visual C++ will keep
reporting the file has changed. Setting this option causes the two timestamps to
match, and Visual C++ is happy.
Default: dos filetime resolution = no
dos filetimes (S)
Under DOS and Windows, if a user can write to a file they can change the timestamp on
it. Under POSIX semantics, only the owner of the file or root may change the
timestamp. By default, Samba emulates the DOS semantics and allows one to change the
timestamp on a file if the user smbd is acting on behalf has write permissions. Due to
changes in Microsoft Office 2000 and beyond, the default for this parameter has been
changed from "no" to "yes" in Samba 3.0.14 and above. Microsoft Excel will display
dialog box warnings about the file being changed by another user if this parameter is
not set to "yes" and files are being shared between users.
Default: dos filetimes = yes
dsdb event notification (G)
When enabled, this option causes Samba (acting as an Active Directory Domain
Controller) to stream Samba database events across the internal message bus. Scripts
built using Samba's python bindings can listen to these events by registering as the
service dsdb_event.
This is not needed for the audit logging described in log level.
Instead, this should instead be considered a developer option (it assists in the Samba
testsuite) rather than a facility for external auditing, as message delivery is not
guaranteed (a feature that the testsuite works around).
The Samba database events are also logged via the normal logging methods when the log
level is set appropriately, say to dsdb_json_audit:5.
Default: dsdb event notification = no
dsdb group change notification (G)
When enabled, this option causes Samba (acting as an Active Directory Domain
Controller) to stream group membership change events across the internal message bus.
Scripts built using Samba's python bindings can listen to these events by registering
as the service dsdb_group_event.
This is not needed for the audit logging described in log level.
Instead, this should instead be considered a developer option (it assists in the Samba
testsuite) rather than a facility for external auditing, as message delivery is not
guaranteed (a feature that the testsuite works around).
The Samba database events are also logged via the normal logging methods when the log
level is set appropriately, say to dsdb_group_json_audit:5.
Default: dsdb group change notification = no
dsdb password event notification (G)
When enabled, this option causes Samba (acting as an Active Directory Domain
Controller) to stream password change and reset events across the internal message
bus. Scripts built using Samba's python bindings can listen to these events by
registering as the service password_event.
This is not needed for the audit logging described in log level.
Instead, this should instead be considered a developer option (it assists in the Samba
testsuite) rather than a facility for external auditing, as message delivery is not
guaranteed (a feature that the testsuite works around).
The Samba database events are also logged via the normal logging methods when the log
level is set appropriately, say to dsdb_password_json_audit:5.
Default: dsdb password event notification = no
durable handles (S)
This boolean parameter controls whether Samba can grant SMB2 durable file handles on a
share.
Note that durable handles are only enabled if kernel oplocks = no, kernel share modes
= no, and posix locking = no, i.e. if the share is configured for CIFS/SMB2 only
access, not supporting interoperability features with local UNIX processes or NFS
operations.
Also note that, for the time being, durability is not granted for a handle that has
the delete on close flag set.
Default: durable handles = yes
ea support (S)
This boolean parameter controls whether smbd(8) will allow clients to attempt to
access extended attributes on a share. In order to enable this parameter on a setup
with default VFS modules:
• Samba must have been built with extended attributes support.
• The underlying filesystem exposed by the share must support extended
attributes (e.g. the getfattr(1) / setfattr(1) utilities must work).
• Access to extended user attributes must be allowed by the underlying
filesystem (e.g. when mounted with a system-dependent option like
user_xattr on Linux).
This option exposes the "user" attribute namespace from the underlying filesystem to
clients. In order to match Windows conventions, the namespace prefix ("user.") is
stripped from the attribute name on the client side. The handling of further attribute
namespaces (like "security", "system", or "trusted") is not affected by this option.
Note that the SMB protocol allows setting attributes whose value is 64K bytes long,
and that on NTFS, the maximum storage space for extended attributes per file is 64K.
On some filesystem the limits may be lower. Filesystems with too limited EA space may
experience unexpected weird effects. The default has changed to yes in Samba release
4.9.0 and above to allow better Windows fileserver compatibility in a default install.
Default: ea support = yes
elasticsearch:address (S)
Specifies the name of the Elasticsearch server to use for Spotlight queries when using
the Elasticsearch backend.
Default: elasticsearch:address = localhost
Example: elasticsearch:address = needle.haystack.samba.org
elasticsearch:ignore unknown attribute (G)
Ignore unknown Spotlight attributes in search queries. An example query using the
unsupported attribute "kMDItemTopic" would be kMDItemTopic=="hotstuff". By default any
query using such a type would completely fail. By enabling this option, if the type
match is a subexpression of a larger expression, then this subexpression is just
ignored.
Default: elasticsearch:ignore unknown attribute = no
Example: elasticsearch:ignore unknown attribute = yes
elasticsearch:ignore unknown type (G)
Ignore unknown Spotlight types in search queries. An example query using the
unsupported type "public.calendar-event" would be
kMDItemContentType=="public.calendar-event". By default any query using such a type
would completely fail. By enabling this option, if the type match is a subexpression
of a larger expression, then this subexpression is just ignored.
Default: elasticsearch:ignore unknown type = no
Example: elasticsearch:ignore unknown type = yes
elasticsearch:index (S)
Specifies the name of the Elasticsearch index to use for Spotlight queries when using
the Elasticsearch backend. The default value of "_all" is a special Elasticsearch
value that performs the search operation on all indices.
Default: elasticsearch:index = _all
Example: elasticsearch:index = spotlight
elasticsearch:mappings (G)
Path to a file specifying metadata attribute mappings in JSON format. Use by the
Elasticsearch backend of the Spotlight RPC service.
Default: elasticsearch:mappings = /usr/share/samba/elasticsearch_mappings.json
Example: elasticsearch:mappings = /usr/share/foo/mymappings.json
elasticsearch:max results (S)
Path to a file specifying metadata attribute mappings in JSON format. Used by the
Elasticsearch backend of the Spotlight RPC service. A value of 0 means no limit.
Default: elasticsearch:max results = 100
Example: elasticsearch:max results = 10
elasticsearch:port (S)
Specifies the TCP port of the Elasticsearch server to use for Spotlight queries when
using the Elasticsearch backend.
Default: elasticsearch:port = 9200
Example: elasticsearch:port = 9201
elasticsearch:use tls (S)
Specifies whether to use HTTPS when talking to the Elasticsearch server used for
Spotlight queries when using the Elasticsearch backend.
Default: elasticsearch:use tls = no
Example: elasticsearch:use tls = yes
enable asu support (G)
Hosts running the "Advanced Server for Unix (ASU)" product require some special
accommodations such as creating a builtin [ADMIN$] share that only supports IPC
connections. The has been the default behavior in smbd for many years. However,
certain Microsoft applications such as the Print Migrator tool require that the remote
server support an [ADMIN$] file share. Disabling this parameter allows for creating an
[ADMIN$] file share in smb.conf.
Default: enable asu support = no
enable core files (G)
This parameter specifies whether core dumps should be written on internal exits.
Normally set to yes. You should never need to change this.
Default: enable core files = yes
Example: enable core files = no
enable privileges (G)
This deprecated parameter controls whether or not smbd will honor privileges assigned
to specific SIDs via either net rpc rights or one of the Windows user and group
manager tools. This parameter is enabled by default. It can be disabled to prevent
members of the Domain Admins group from being able to assign privileges to users or
groups which can then result in certain smbd operations running as root that would
normally run under the context of the connected user.
An example of how privileges can be used is to assign the right to join clients to a
Samba controlled domain without providing root access to the server via smbd.
Please read the extended description provided in the Samba HOWTO documentation.
Default: enable privileges = yes
enable spoolss (G)
Inverted synonym for disable spoolss.
Default: enable spoolss = yes
encrypt passwords (G)
This parameter has been deprecated since Samba 4.11 and support for plaintext (as
distinct from NTLM, NTLMv2 or Kerberos authentication) will be removed in a future
Samba release.
That is, in the future, the current default of encrypt passwords = yes will be the
enforced behaviour.
This boolean controls whether encrypted passwords will be negotiated with the client.
Note that Windows NT 4.0 SP3 and above and also Windows 98 will by default expect
encrypted passwords unless a registry entry is changed. To use encrypted passwords in
Samba see the chapter "User Database" in the Samba HOWTO Collection.
MS Windows clients that expect Microsoft encrypted passwords and that do not have
plain text password support enabled will be able to connect only to a Samba server
that has encrypted password support enabled and for which the user accounts have a
valid encrypted password. Refer to the smbpasswd command man page for information
regarding the creation of encrypted passwords for user accounts.
The use of plain text passwords is NOT advised as support for this feature is no
longer maintained in Microsoft Windows products. If you want to use plain text
passwords you must set this parameter to no.
In order for encrypted passwords to work correctly smbd(8) must either have access to
a local smbpasswd(5) file (see the smbpasswd(8) program for information on how to set
up and maintain this file), or set the security = [domain|ads] parameter which causes
smbd to authenticate against another server.
Default: encrypt passwords = yes
enhanced browsing (G)
This option enables a couple of enhancements to cross-subnet browse propagation that
have been added in Samba but which are not standard in Microsoft implementations.
The first enhancement to browse propagation consists of a regular wildcard query to a
Samba WINS server for all Domain Master Browsers, followed by a browse synchronization
with each of the returned DMBs. The second enhancement consists of a regular
randomised browse synchronization with all currently known DMBs.
You may wish to disable this option if you have a problem with empty workgroups not
disappearing from browse lists. Due to the restrictions of the browse protocols, these
enhancements can cause a empty workgroup to stay around forever which can be annoying.
In general you should leave this option enabled as it makes cross-subnet browse
propagation much more reliable.
Default: enhanced browsing = yes
enumports command (G)
The concept of a "port" is fairly foreign to UNIX hosts. Under Windows NT/2000 print
servers, a port is associated with a port monitor and generally takes the form of a
local port (i.e. LPT1:, COM1:, FILE:) or a remote port (i.e. LPD Port Monitor,
etc...). By default, Samba has only one port defined--"Samba Printer Port". Under
Windows NT/2000, all printers must have a valid port name. If you wish to have a list
of ports displayed (smbd does not use a port name for anything) other than the default
"Samba Printer Port", you can define enumports command to point to a program which
should generate a list of ports, one per line, to standard output. This listing will
then be used in response to the level 1 and 2 EnumPorts() RPC.
Default: enumports command =
Example: enumports command = /usr/bin/listports
eventlog list (G)
This option defines a list of log names that Samba will report to the Microsoft
EventViewer utility. The listed eventlogs will be associated with tdb file on disk in
the $(statedir)/eventlog.
The administrator must use an external process to parse the normal Unix logs such as
/var/log/messages and write then entries to the eventlog tdb files. Refer to the
eventlogadm(8) utility for how to write eventlog entries.
Default: eventlog list =
Example: eventlog list = Security Application Syslog Apache
fake directory create times (S)
NTFS and Windows VFAT file systems keep a create time for all files and directories.
This is not the same as the ctime - status change time - that Unix keeps, so Samba by
default reports the earliest of the various times Unix does keep. Setting this
parameter for a share causes Samba to always report midnight 1-1-1980 as the create
time for directories.
This option is mainly used as a compatibility option for Visual C++ when used against
Samba shares. Visual C++ generated makefiles have the object directory as a dependency
for each object file, and a make rule to create the directory. Also, when NMAKE
compares timestamps it uses the creation time when examining a directory. Thus the
object directory will be created if it does not exist, but once it does exist it will
always have an earlier timestamp than the object files it contains.
However, Unix time semantics mean that the create time reported by Samba will be
updated whenever a file is created or deleted in the directory. NMAKE finds all object
files in the object directory. The timestamp of the last one built is then compared to
the timestamp of the object directory. If the directory's timestamp if newer, then all
object files will be rebuilt. Enabling this option ensures directories always predate
their contents and an NMAKE build will proceed as expected.
Default: fake directory create times = no
fake oplocks (S)
Oplocks are the way that SMB clients get permission from a server to locally cache
file operations. If a server grants an oplock (opportunistic lock) then the client is
free to assume that it is the only one accessing the file and it will aggressively
cache file data. With some oplock types the client may even cache file open/close
operations. This can give enormous performance benefits.
When you set fake oplocks = yes, smbd(8) will always grant oplock requests no matter
how many clients are using the file.
It is generally much better to use the real oplocks support rather than this
parameter.
If you enable this option on all read-only shares or shares that you know will only be
accessed from one client at a time such as physically read-only media like CDROMs, you
will see a big performance improvement on many operations. If you enable this option
on shares where multiple clients may be accessing the files read-write at the same
time you can get data corruption. Use this option carefully!
Default: fake oplocks = no
follow symlinks (S)
This parameter allows the Samba administrator to stop smbd(8) from following symbolic
links in a particular share. Setting this parameter to no prevents any file or
directory that is a symbolic link from being followed (the user will get an error).
This option is very useful to stop users from adding a symbolic link to /etc/passwd in
their home directory for instance. However it will slow filename lookups down
slightly.
This option is enabled (i.e. smbd will follow symbolic links) by default.
Default: follow symlinks = yes
smbd force process locks (S)
This boolean option tells smbd whether to forcefully disable the use of Open File
Description locks on Linux.
This option should not be changed from the default unless you know what you're doing.
Default: smbd force process locks = no
force create mode (S)
This parameter specifies a set of UNIX mode bit permissions that will always be set on
a file created by Samba. This is done by bitwise 'OR'ing these bits onto the mode bits
of a file that is being created. The default for this parameter is (in octal) 000. The
modes in this parameter are bitwise 'OR'ed onto the file mode after the mask set in
the create mask parameter is applied.
The example below would force all newly created files to have read and execute
permissions set for 'group' and 'other' as well as the read/write/execute bits set for
the 'user'.
Default: force create mode = 0000
Example: force create mode = 0755
force directory mode (S)
This parameter specifies a set of UNIX mode bit permissions that will always be set on
a directory created by Samba. This is done by bitwise 'OR'ing these bits onto the mode
bits of a directory that is being created. The default for this parameter is (in
octal) 0000 which will not add any extra permission bits to a created directory. This
operation is done after the mode mask in the parameter directory mask is applied.
The example below would force all created directories to have read and execute
permissions set for 'group' and 'other' as well as the read/write/execute bits set for
the 'user'.
Default: force directory mode = 0000
Example: force directory mode = 0755
force directory security mode (S)
This parameter has been removed for Samba 4.0.0.
No default
group
This parameter is a synonym for force group.
force group (S)
This specifies a UNIX group name that will be assigned as the default primary group
for all users connecting to this service. This is useful for sharing files by ensuring
that all access to files on service will use the named group for their permissions
checking. Thus, by assigning permissions for this group to the files and directories
within this service the Samba administrator can restrict or allow sharing of these
files.
In Samba 2.0.5 and above this parameter has extended functionality in the following
way. If the group name listed here has a '+' character prepended to it then the
current user accessing the share only has the primary group default assigned to this
group if they are already assigned as a member of that group. This allows an
administrator to decide that only users who are already in a particular group will
create files with group ownership set to that group. This gives a finer granularity of
ownership assignment. For example, the setting force group = +sys means that only
users who are already in group sys will have their default primary group assigned to
sys when accessing this Samba share. All other users will retain their ordinary
primary group.
If the force user parameter is also set the group specified in force group will
override the primary group set in force user.
Default: force group =
Example: force group = agroup
force printername (S)
When printing from Windows NT (or later), each printer in smb.conf has two associated
names which can be used by the client. The first is the sharename (or shortname)
defined in smb.conf. This is the only printername available for use by Windows 9x
clients. The second name associated with a printer can be seen when browsing to the
"Printers" (or "Printers and Faxes") folder on the Samba server. This is referred to
simply as the printername (not to be confused with the printer name option).
When assigning a new driver to a printer on a remote Windows compatible print server
such as Samba, the Windows client will rename the printer to match the driver name
just uploaded. This can result in confusion for users when multiple printers are bound
to the same driver. To prevent Samba from allowing the printer's printername to differ
from the sharename defined in smb.conf, set force printername = yes.
Be aware that enabling this parameter may affect migrating printers from a Windows
server to Samba since Windows has no way to force the sharename and printername to
match.
It is recommended that this parameter's value not be changed once the printer is in
use by clients as this could cause a user not be able to delete printer connections
from their local Printers folder.
Default: force printername = no
force security mode (S)
This parameter has been removed for Samba 4.0.0.
No default
force unknown acl user (S)
If this parameter is set, a Windows NT ACL that contains an unknown SID (security
descriptor, or representation of a user or group id) as the owner or group owner of
the file will be silently mapped into the current UNIX uid or gid of the currently
connected user.
This is designed to allow Windows NT clients to copy files and folders containing ACLs
that were created locally on the client machine and contain users local to that
machine only (no domain users) to be copied to a Samba server (usually with XCOPY /O)
and have the unknown userid and groupid of the file owner map to the current connected
user. This can only be fixed correctly when winbindd allows arbitrary mapping from any
Windows NT SID to a UNIX uid or gid.
Try using this parameter when XCOPY /O gives an ACCESS_DENIED error.
Default: force unknown acl user = no
force user (S)
This specifies a UNIX user name that will be assigned as the default user for all
users connecting to this service. This is useful for sharing files. You should also
use it carefully as using it incorrectly can cause security problems.
This user name only gets used once a connection is established. Thus clients still
need to connect as a valid user and supply a valid password. Once connected, all file
operations will be performed as the "forced user", no matter what username the client
connected as. This can be very useful.
In Samba 2.0.5 and above this parameter also causes the primary group of the forced
user to be used as the primary group for all file activity. Prior to 2.0.5 the primary
group was left as the primary group of the connecting user (this was a bug).
Default: force user =
Example: force user = auser
fss: prune stale (G)
When enabled, Samba's File Server Remote VSS Protocol (FSRVP) server checks all FSRVP
initiated snapshots on startup, and removes any corresponding state (including share
definitions) for nonexistent snapshot paths.
Default: fss: prune stale = no
Example: fss: prune stale = yes
fss: sequence timeout (G)
The File Server Remote VSS Protocol (FSRVP) server includes a message sequence timer
to ensure cleanup on unexpected client disconnect. This parameter overrides the
default timeout between FSRVP operations. FSRVP timeouts can be completely disabled
via a value of 0.
Default: fss: sequence timeout = 180 or 1800, depending on operation
Example: fss: sequence timeout = 0
fstype (S)
This parameter allows the administrator to configure the string that specifies the
type of filesystem a share is using that is reported by smbd(8) when a client queries
the filesystem type for a share. The default type is NTFS for compatibility with
Windows NT but this can be changed to other strings such as Samba or FAT if required.
Default: fstype = NTFS
Example: fstype = Samba
get quota command (G)
The get quota command should only be used whenever there is no operating system API
available from the OS that samba can use.
This option is only available Samba was compiled with quotas support.
This parameter should specify the path to a script that queries the quota information
for the specified user/group for the partition that the specified directory is on.
Such a script is being given 3 arguments:
• directory
• type of query
• uid of user or gid of group
The directory is actually mostly just "." - It needs to be treated relatively to the
current working directory that the script can also query.
The type of query can be one of:
• 1 - user quotas
• 2 - user default quotas (uid = -1)
• 3 - group quotas
• 4 - group default quotas (gid = -1)
This script should print one line as output with spaces between the columns. The
printed columns should be:
• 1 - quota flags (0 = no quotas, 1 = quotas enabled, 2 = quotas enabled and
enforced)
• 2 - number of currently used blocks
• 3 - the softlimit number of blocks
• 4 - the hardlimit number of blocks
• 5 - currently used number of inodes
• 6 - the softlimit number of inodes
• 7 - the hardlimit number of inodes
• 8 (optional) - the number of bytes in a block(default is 1024)
Default: get quota command =
Example: get quota command = /usr/local/sbin/query_quota
getwd cache (G)
This is a tuning option. When this is enabled a caching algorithm will be used to
reduce the time taken for getwd() calls. This can have a significant impact on
performance, especially when the wide links parameter is set to no.
Default: getwd cache = yes
gpo update command (G)
This option sets the command that is called to apply GPO policies. The samba-gpupdate
script applies System Access and Kerberos Policies to the KDC. System Access policies
set minPwdAge, maxPwdAge, minPwdLength, and pwdProperties in the samdb. Kerberos
Policies set kdc:service ticket lifetime, kdc:user ticket lifetime, and kdc:renewal
lifetime in smb.conf.
Default: gpo update command = /usr/sbin/samba-gpupdate
Example: gpo update command = /usr/local/sbin/gpoupdate
guest account (G)
This is a username which will be used for access to services which are specified as
guest ok (see below). Whatever privileges this user has will be available to any
client connecting to the guest service. This user must exist in the password file, but
does not require a valid login. The user account "ftp" is often a good choice for this
parameter.
On some systems the default guest account "nobody" may not be able to print. Use
another account in this case. You should test this by trying to log in as your guest
user (perhaps by using the su - command) and trying to print using the system print
command such as lpr(1) or lp(1).
This parameter does not accept % macros, because many parts of the system require this
value to be constant for correct operation.
Default: guest account = nobody # default can be changed at compile-time
Example: guest account = ftp
public
This parameter is a synonym for guest ok.
guest ok (S)
If this parameter is yes for a service, then no password is required to connect to the
service. Privileges will be those of the guest account.
This parameter nullifies the benefits of setting restrict anonymous = 2
See the section below on security for more information about this option.
Default: guest ok = no
only guest
This parameter is a synonym for guest only.
guest only (S)
If this parameter is yes for a service, then only guest connections to the service are
permitted. This parameter will have no effect if guest ok is not set for the service.
See the section below on security for more information about this option.
Default: guest only = no
hide dot files (S)
This is a boolean parameter that controls whether files starting with a dot appear as
hidden files.
Default: hide dot files = yes
hide files (S)
This is a list of files or directories that are not visible but are accessible. The
DOS 'hidden' attribute is applied to any files or directories that match.
Each entry in the list must be separated by a '/', which allows spaces to be included
in the entry. '*' and '?' can be used to specify multiple files or directories as in
DOS wildcards.
Each entry must be a Unix path, not a DOS path and must not include the Unix directory
separator '/'.
Note that the case sensitivity option is applicable in hiding files.
Setting this parameter will affect the performance of Samba, as it will be forced to
check all files and directories for a match as they are scanned.
The example shown above is based on files that the Macintosh SMB client (DAVE)
available from Thursby creates for internal use, and also still hides all files
beginning with a dot.
An example of us of this parameter is:
hide files = /.*/DesktopFolderDB/TrashFor%m/resource.frk/
Default: hide files = # no file are hidden
hide new files timeout (S)
Setting this parameter to something but 0 hides files that have been modified less
than N seconds ago.
It can be used for ingest/process queue style workloads. A processing application
should only see files that are definitely finished. As many applications do not have
proper external workflow control, this can be a way to make sure processing does not
interfere with file ingest.
Default: hide new files timeout = 0
hide special files (S)
This parameter prevents clients from seeing special files such as sockets, devices and
fifo's in directory listings.
Default: hide special files = no
hide unreadable (S)
This parameter prevents clients from seeing the existence of files that cannot be
read. Defaults to off.
Please note that enabling this can slow down listing large directories significantly.
Samba has to evaluate the ACLs of all directory members, which can be a lot of effort.
Default: hide unreadable = no
hide unwriteable files (S)
This parameter prevents clients from seeing the existence of files that cannot be
written to. Defaults to off. Note that unwriteable directories are shown as usual.
Please note that enabling this can slow down listing large directories significantly.
Samba has to evaluate the ACLs of all directory members, which can be a lot of effort.
Default: hide unwriteable files = no
honor change notify privilege (S)
This option can be used to make use of the change notify privilege. By default notify
results are not checked against the file system permissions.
If "honor change notify privilege" is enabled, a user will only receive notify
results, if he has change notify privilege or sufficient file system permissions. If a
user has the change notify privilege, he will receive all requested notify results,
even if the user does not have the permissions on the file system.
Default: honor change notify privilege = no
host msdfs (G)
If set to yes, Samba will act as a Dfs server, and allow Dfs-aware clients to browse
Dfs trees hosted on the server.
See also the msdfs root share level parameter. For more information on setting up a
Dfs tree on Samba, refer to the MSFDS chapter in the book Samba3-HOWTO.
Default: host msdfs = yes
hostname lookups (G)
Specifies whether samba should use (expensive) hostname lookups or use the ip
addresses instead. An example place where hostname lookups are currently used is when
checking the hosts deny and hosts allow.
Default: hostname lookups = no
Example: hostname lookups = yes
allow hosts
This parameter is a synonym for hosts allow.
hosts allow (S)
A synonym for this parameter is allow hosts.
This parameter is a comma, space, or tab delimited set of hosts which are permitted to
access a service.
If specified in the [global] section then it will apply to all services, regardless of
whether the individual service has a different setting.
You can specify the hosts by name or IP number. For example, you could restrict access
to only the hosts on a Class C subnet with something like allow hosts = 150.203.5..
The full syntax of the list is described in the man page hosts_access(5). Note that
this man page may not be present on your system, so a brief description will be given
here also.
Note that the localhost address 127.0.0.1 will always be allowed access unless
specifically denied by a hosts deny option.
You can also specify hosts by network/netmask pairs and by netgroup names if your
system supports netgroups. The EXCEPT keyword can also be used to limit a wildcard
list. The following examples may provide some help:
Example 1: allow all IPs in 150.203.*.*; except one
hosts allow = 150.203. EXCEPT 150.203.6.66
Example 2: allow hosts that match the given network/netmask
hosts allow = 150.203.15.0/255.255.255.0
Example 3: allow a couple of hosts
hosts allow = lapland, arvidsjaur
Example 4: allow only hosts in NIS netgroup "foonet", but deny access from one
particular host
hosts allow = @foonet
hosts deny = pirate
Note
Note that access still requires suitable user-level passwords.
See testparm(1) for a way of testing your host access to see if it does what you
expect.
Default: hosts allow = # none (i.e., all hosts permitted access)
Example: hosts allow = 150.203.5. myhost.mynet.edu.au
deny hosts
This parameter is a synonym for hosts deny.
hosts deny (S)
The opposite of hosts allow - hosts listed here are NOT permitted access to services
unless the specific services have their own lists to override this one. Where the
lists conflict, the allow list takes precedence.
In the event that it is necessary to deny all by default, use the keyword ALL (or the
netmask 0.0.0.0/0) and then explicitly specify to the hosts allow = hosts allow
parameter those hosts that should be permitted access.
Default: hosts deny = # none (i.e., no hosts specifically excluded)
Example: hosts deny = 150.203.4. badhost.mynet.edu.au
idmap backend (G)
The idmap backend provides a plugin interface for Winbind to use varying backends to
store SID/uid/gid mapping tables.
This option specifies the default backend that is used when no special configuration
set, but it is now deprecated in favour of the new spelling idmap config * : backend.
Default: idmap backend = tdb
idmap cache time (G)
This parameter specifies the number of seconds that Winbind's idmap interface will
cache positive SID/uid/gid query results. By default, Samba will cache these results
for one week.
Default: idmap cache time = 604800
idmap config DOMAIN : OPTION (G)
ID mapping in Samba is the mapping between Windows SIDs and Unix user and group IDs.
This is performed by Winbindd with a configurable plugin interface. Samba's ID mapping
is configured by options starting with the idmap config prefix. An idmap option
consists of the idmap config prefix, followed by a domain name or the asterisk
character (*), a colon, and the name of an idmap setting for the chosen domain.
The idmap configuration is hence divided into groups, one group for each domain to be
configured, and one group with the asterisk instead of a proper domain name, which
specifies the default configuration that is used to catch all domains that do not have
an explicit idmap configuration of their own.
There are three general options available:
backend = backend_name
This specifies the name of the idmap plugin to use as the SID/uid/gid backend for
this domain. The standard backends are tdb (idmap_tdb(8)), tdb2 (idmap_tdb2(8)),
ldap (idmap_ldap(8)), rid (idmap_rid(8)), hash (idmap_hash(8)), autorid
(idmap_autorid(8)), ad (idmap_ad(8)) and nss (idmap_nss(8)). The corresponding
manual pages contain the details, but here is a summary.
The first three of these create mappings of their own using internal unixid
counters and store the mappings in a database. These are suitable for use in the
default idmap configuration. The rid and hash backends use a pure algorithmic
calculation to determine the unixid for a SID. The autorid module is a mixture of
the tdb and rid backend. It creates ranges for each domain encountered and then
uses the rid algorithm for each of these automatically configured domains
individually. The ad backend uses unix ids stored in Active Directory via the
standard schema extensions. The nss backend reverses the standard winbindd setup
and gets the unix ids via names from nsswitch which can be useful in an ldap
setup.
range = low - high
Defines the available matching uid and gid range for which the backend is
authoritative. For allocating backends, this also defines the start and the end of
the range for allocating new unique IDs.
winbind uses this parameter to find the backend that is authoritative for a unix
ID to SID mapping, so it must be set for each individually configured domain and
for the default configuration. The configured ranges must be mutually disjoint.
Note that the low value interacts with the min domain uid option!
read only = yes|no
This option can be used to turn the writing backends tdb, tdb2, and ldap into read
only mode. This can be useful e.g. in cases where a pre-filled database exists
that should not be extended automatically.
The following example illustrates how to configure the idmap_ad(8) backend for the
CORP domain and the idmap_tdb(8) backend for all other domains. This configuration
assumes that the admin of CORP assigns unix ids below 1000000 via the SFU extensions,
and winbind is supposed to use the next million entries for its own mappings from
trusted domains and for local groups for example.
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999
idmap config CORP : backend = ad
idmap config CORP : range = 1000-999999
No default
winbind gid
This parameter is a synonym for idmap gid.
idmap gid (G)
The idmap gid parameter specifies the range of group ids for the default idmap
configuration. It is now deprecated in favour of idmap config * : range.
See the idmap config option.
Default: idmap gid =
Example: idmap gid = 10000-20000
idmap negative cache time (G)
This parameter specifies the number of seconds that Winbind's idmap interface will
cache negative SID/uid/gid query results.
Default: idmap negative cache time = 120
winbind uid
This parameter is a synonym for idmap uid.
idmap uid (G)
The idmap uid parameter specifies the range of user ids for the default idmap
configuration. It is now deprecated in favour of idmap config * : range.
See the idmap config option.
Default: idmap uid =
Example: idmap uid = 10000-20000
include (S)
This allows you to include one config file inside another. The file is included
literally, as though typed in place.
It takes the standard substitutions, except %u, %P and %S.
The parameter include = registry has a special meaning: It does not include a file
named registry from the current working directory, but instead reads the global
configuration options from the registry. See the section on registry-based
configuration for details. Note that this option automatically activates registry
shares.
Default: include =
Example: include = /usr/local/samba/lib/admin_smb.conf
include system krb5 conf (G)
Setting this parameter to no will prevent winbind to include the system /etc/krb5.conf
file into the krb5.conf file it creates. See also create krb5 conf. This option only
applies to Samba built with MIT Kerberos.
Default: include system krb5 conf = yes
inherit acls (S)
This parameter is only relevant for filesystems that do not support standardized NFS4
ACLs but only a POSIX draft ACL implementation and which implements default ACLs like
most filesystems on Linux. It can be used to ensure that if default ACLs exist on
parent directories, they are always honored when creating a new file or subdirectory
in these parent directories. The default behavior is to use the unix mode specified
when creating the directory. Enabling this option sets the unix mode to 0777, thus
guaranteeing that the default directory ACLs are propagated. Note that using the VFS
modules acl_xattr or acl_tdb which store native Windows as meta-data will
automatically turn this option on for any share for which they are loaded, as they
require this option to emulate Windows ACLs correctly.
Default: inherit acls = no
inherit owner (S)
The ownership of new files and directories is normally governed by effective uid of
the connected user. This option allows the Samba administrator to specify that the
ownership for new files and directories should be controlled by the ownership of the
parent directory.
Valid options are:
• no - Both the Windows (SID) owner and the UNIX (uid) owner of the file are
governed by the identity of the user that created the file.
• windows and unix - The Windows (SID) owner and the UNIX (uid) owner of new
files and directories are set to the respective owner of the parent
directory.
• yes - a synonym for windows and unix.
• unix only - Only the UNIX owner is set to the UNIX owner of the parent
directory.
Common scenarios where this behavior is useful is in implementing drop-boxes, where
users can create and edit files but not delete them and ensuring that newly created
files in a user's roaming profile directory are actually owned by the user.
The unix only option effectively breaks the tie between the Windows owner of a file
and the UNIX owner. As a logical consequence, in this mode, setting the Windows owner
of a file does not modify the UNIX owner. Using this mode should typically be combined
with a backing store that can emulate the full NT ACL model without affecting the
POSIX permissions, such as the acl_xattr VFS module, coupled with acl_xattr:ignore
system acls = yes. This can be used to emulate folder quotas, when files are exposed
only via SMB (without UNIX extensions). The UNIX owner of a directory is locally set
and inherited by all subdirectories and files, and they all consume the same quota.
Default: inherit owner = no
inherit permissions (S)
The permissions on new files and directories are normally governed by create mask,
directory mask, force create mode and force directory mode but the boolean inherit
permissions parameter overrides this.
New directories inherit the mode of the parent directory, including bits such as
setgid.
New files inherit their read/write bits from the parent directory. Their execute bits
continue to be determined by map archive, map hidden and map system as usual.
Note that the setuid bit is never set via inheritance (the code explicitly prohibits
this).
This can be particularly useful on large systems with many users, perhaps several
thousand, to allow a single [homes] share to be used flexibly by each user.
Default: inherit permissions = no
init logon delay (G)
This parameter specifies a delay in milliseconds for the hosts configured for delayed
initial samlogon with init logon delayed hosts.
Default: init logon delay = 100
init logon delayed hosts (G)
This parameter takes a list of host names, addresses or networks for which the initial
samlogon reply should be delayed (so other DCs get preferred by XP workstations if
there are any).
The length of the delay can be specified with the init logon delay parameter.
Default: init logon delayed hosts =
Example: init logon delayed hosts = 150.203.5. myhost.mynet.de
interfaces (G)
This option allows you to override the default network interfaces list that Samba will
use for browsing, name registration and other NetBIOS over TCP/IP (NBT) traffic. By
default Samba will query the kernel for the list of all active interfaces and use any
interfaces except 127.0.0.1 that are broadcast capable.
The option takes a list of interface strings. Each string can be in any of the
following forms:
• a network interface name (such as eth0). This may include shell-like
wildcards so eth* will match any interface starting with the substring
"eth"
• an IP address. In this case the netmask is determined from the list of
interfaces obtained from the kernel
• an IP/mask pair.
• a broadcast/mask pair.
The "mask" parameters can either be a bit length (such as 24 for a C class network) or
a full netmask in dotted decimal form.
The "IP" parameters above can either be a full dotted decimal IP address or a hostname
which will be looked up via the OS's normal hostname resolution mechanisms.
By default Samba enables all active interfaces that are broadcast capable except the
loopback adaptor (IP address 127.0.0.1).
In order to support SMB3 multi-channel configurations, smbd understands some extra
parameters which can be appended after the actual interface with this extended syntax
(note that the quoting is important in order to handle the ; and , characters):
"interface[;key1=value1[,key2=value2[...]]]"
Known keys are speed, capability, and if_index. Speed is specified in bits per second.
Known capabilities are RSS and RDMA. The if_index should be used with care: the values
must not coincide with indexes used by the kernel. Note that these options are mainly
intended for testing and development rather than for production use. At least on Linux
systems, these values should be auto-detected, but the settings can serve as last a
resort when autodetection is not working or is not available. The specified values
overwrite the auto-detected values.
The first two example below configures three network interfaces corresponding to the
eth0 device and IP addresses 192.168.2.10 and 192.168.3.10. The netmasks of the latter
two interfaces would be set to 255.255.255.0.
The other examples show how per interface extra parameters can be specified. Notice
the possible usage of "," and ";", which makes the double quoting necessary.
Default: interfaces =
Example: interfaces = eth0 192.168.2.10/24 192.168.3.10/255.255.255.0
Example: interfaces = eth0, 192.168.2.10/24; 192.168.3.10/255.255.255.0
Example: interfaces = "eth0;if_index=65,speed=1000000000,capability=RSS"
Example: interfaces = "lo;speed=1000000000" "eth0;capability=RSS"
Example: interfaces = "lo;speed=1000000000" , "eth0;capability=RSS"
Example: interfaces = "eth0;capability=RSS" , "rdma1;capability=RDMA" ;
"rdma2;capability=RSS,capability=RDMA"
invalid users (S)
This is a list of users that should not be allowed to login to this service. This is
really a paranoid check to absolutely ensure an improper setting does not breach your
security.
A name starting with a '@' is interpreted as an NIS netgroup first (if your system
supports NIS), and then as a UNIX group if the name was not found in the NIS netgroup
database.
A name starting with '+' is interpreted only by looking in the UNIX group database via
the NSS getgrnam() interface. A name starting with '&' is interpreted only by looking
in the NIS netgroup database (this requires NIS to be working on your system). The
characters '+' and '&' may be used at the start of the name in either order so the
value +&group means check the UNIX group database, followed by the NIS netgroup
database, and the value &+group means check the NIS netgroup database, followed by the
UNIX group database (the same as the '@' prefix).
The current servicename is substituted for %S. This is useful in the [homes] section.
Default: invalid users = # no invalid users
Example: invalid users = root fred admin @wheel
iprint server (G)
This parameter is only applicable if printing is set to iprint.
If set, this option overrides the ServerName option in the CUPS client.conf. This is
necessary if you have virtual samba servers that connect to different CUPS daemons.
Default: iprint server = ""
Example: iprint server = MYCUPSSERVER
kdc default domain supported enctypes (G)
Set the default value of msDS-SupportedEncryptionTypes for service accounts in Active
Directory that are missing this value or where msDS-SupportedEncryptionTypes is set to
0.
This allows Samba administrators to match the configuration flexibility provided by
the
HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\KDC\DefaultDomainSupportedEncTypes
Registry Value on Windows.
Unlike the Windows registry key (which only takes an base-10 number), in Samba this
may also be expressed in hexadecimal or as a list of Kerberos encryption type names.
Specified values are ORed together bitwise, and those currently supported consist of:
• arcfour-hmac-md5, rc4-hmac, 0x4, or 4
Known on Windows as Kerberos RC4 encryption
• aes128-cts-hmac-sha1-96, aes128-cts, 0x8, or 8
Known on Windows as Kerberos AES 128 bit encryption
• aes256-cts-hmac-sha1-96, aes256-cts, 0x10, or 16
Known on Windows as Kerberos AES 256 bit encryption
• aes256-cts-hmac-sha1-96-sk, aes256-cts-sk, 0x20, or 32
Allow AES session keys. When this is set, it indicates to the KDC that AES
session keys can be used, even when aes256-cts and aes128-cts are not set.
This allows use of AES keys against hosts otherwise only configured with
RC4 for ticket keys (which is the default).
Default: kdc default domain supported enctypes = 0 # maps to what the software
supports currently: arcfour-hmac-md5 aes256-cts-hmac-sha1-96-sk
kdc enable fast (G)
With the Samba 4.16 the embedded Heimdal KDC brings support for RFC6113 FAST, which
wasn't available in older Samba versions.
This option is mostly for testing and currently only applies if the embedded Heimdal
KDC is used.
Default: kdc enable fast = yes
kdc force enable rc4 weak session keys (G)
RFC8429 declares that rc4-hmac Kerberos ciphers are weak and there are known attacks
on Active Directory use of this cipher suite.
However for compatibility with Microsoft Windows this option allows the KDC to assume
that regardless of the value set in a service account's msDS-SupportedEncryptionTypes
attribute that a rc4-hmac Kerberos session key (as distinct from the ticket key, as
found in a service keytab) can be used if the potentially older client requests it.
Default: kdc force enable rc4 weak session keys = no
kdc supported enctypes (G)
On an active directory domain controller, this is the list of supported encryption
types for local running kdc.
This allows Samba administrators to remove support for weak/unused encryption types,
similar the configuration flexibility provided by the Network security: Configure
encryption types allowed for Kerberos GPO/Local Policies/Security Options Value, which
results in the
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\Kerberos\Parameters\SupportedEncryptionTypes
Registry Value on Windows.
Unlike the Windows registry key (which only takes an base-10 number), in Samba this
may also be expressed as hexadecimal or a list of Kerberos encryption type names.
Specified values are ORed together bitwise, and those currently supported consist of:
• arcfour-hmac-md5, rc4-hmac, 0x4, or 4
Known on Windows as Kerberos RC4 encryption
• aes128-cts-hmac-sha1-96, aes128-cts, 0x8, or 8
Known on Windows as Kerberos AES 128 bit encryption
• aes256-cts-hmac-sha1-96, aes256-cts, 0x10, or 16
Known on Windows as Kerberos AES 256 bit encryption
Default: kdc supported enctypes = 0 # maps to what the software supports currently:
arcfour-hmac-md5 aes128-cts-hmac-sha1-96 aes256-cts-hmac-sha1-96
keepalive (G)
The value of the parameter (an integer) represents the number of seconds between
keepalive packets. If this parameter is zero, no keepalive packets will be sent.
Keepalive packets, if sent, allow the server to tell whether a client is still present
and responding.
Keepalives should, in general, not be needed if the socket has the SO_KEEPALIVE
attribute set on it by default. (see socket options). Basically you should only use
this option if you strike difficulties.
Please note this option only applies to SMB1 client connections, and has no effect on
SMB2 clients.
Default: keepalive = 300
Example: keepalive = 600
kerberos encryption types (G)
This parameter determines the encryption types to use when operating as a Kerberos
client. Possible values are all, strong, and legacy.
Samba uses a Kerberos library (MIT or Heimdal) to obtain Kerberos tickets. This
library is normally configured outside of Samba, using the krb5.conf file. This file
may also include directives to configure the encryption types to be used. However,
Samba implements Active Directory protocols and algorithms to locate a domain
controller. In order to force the Kerberos library into using the correct domain
controller, some Samba processes, such as winbindd(8) and net(8), build a private
krb5.conf file for use by the Kerberos library while being invoked from Samba. This
private file controls all aspects of the Kerberos library operation, and this
parameter controls how the encryption types are configured within this generated file,
and therefore also controls the encryption types negotiable by Samba.
When set to all, all active directory encryption types are allowed.
When set to strong, only AES-based encryption types are offered. This can be used in
hardened environments to prevent downgrade attacks.
When set to legacy, only RC4-HMAC-MD5 is allowed. AVOID using this option, because of
CVE-2022-37966 see https://bugzilla.samba.org/show_bug.cgi?id=15237.
Default: kerberos encryption types = all
kerberos method (G)
Controls how kerberos tickets are verified.
Valid options are:
• secrets only - use only the secrets.tdb for ticket verification (default)
• system keytab - use only the system keytab for ticket verification
• dedicated keytab - use a dedicated keytab for ticket verification
• secrets and keytab - use the secrets.tdb first, then the system keytab
The major difference between "system keytab" and "dedicated keytab" is that the latter
method relies on kerberos to find the correct keytab entry instead of filtering based
on expected principals.
When the kerberos method is in "dedicated keytab" mode, dedicated keytab file must be
set to specify the location of the keytab file.
Default: kerberos method = default
kernel change notify (G)
This parameter specifies whether Samba should ask the kernel for change notifications
in directories so that SMB clients can refresh whenever the data on the server
changes.
This parameter is only used when your kernel supports change notification to user
programs using the inotify interface.
Default: kernel change notify = yes
kernel oplocks (S)
For UNIXes that support kernel based oplocks (currently only Linux), this parameter
allows the use of them to be turned on or off. However, this disables Level II oplocks
for clients as the Linux kernel does not support them properly.
Kernel oplocks support allows Samba oplocks to be broken whenever a local UNIX process
or NFS operation accesses a file that smbd(8) has oplocked. This allows complete data
consistency between SMB/CIFS, NFS and local file access (and is a very cool feature
:-).
If you do not need this interaction, you should disable the parameter on Linux to get
Level II oplocks and the associated performance benefit.
This parameter defaults to no and is translated to a no-op on systems that do not have
the necessary kernel support.
Default: kernel oplocks = no
kernel share modes (S)
This parameter controls whether SMB share modes are translated into file system
specific sharemode calls.
Kernel share modes provide a minimal level of interoperability with local UNIX
processes and NFS operations by preventing access corresponding to the SMB share
modes. This requires a file system specific VFS module with proper support.
Note that in order to use SMB2 durable file handles on a share, you have to turn
kernel share modes off.
This parameter defaults to no. Setting it to yes requires a file system module that
supports file system sharemodes, otherwise attempts to access files will fail with a
sharing violation.
Default: kernel share modes = no
kpasswd port (G)
Specifies which ports the Kerberos server should listen on for password changes.
Default: kpasswd port = 464
krb5 port (G)
Specifies which port the KDC should listen on for Kerberos traffic.
Default: krb5 port = 88
lanman auth (G)
This parameter has been deprecated since Samba 4.11 and support for LanMan (as
distinct from NTLM, NTLMv2 or Kerberos authentication) will be removed in a future
Samba release.
That is, in the future, the current default of lanman auth = no will be the enforced
behaviour.
This parameter determines whether or not smbd(8) will attempt to authenticate users or
permit password changes using the LANMAN password hash. If disabled, only clients
which support NT password hashes (e.g. Windows NT/2000 clients, smbclient, but not
Windows 95/98 or the MS DOS network client) will be able to connect to the Samba host.
The LANMAN encrypted response is easily broken, due to its case-insensitive nature,
and the choice of algorithm. Servers without Windows 95/98/ME or MS DOS clients are
advised to disable this option.
When this parameter is set to no this will also result in sambaLMPassword in Samba's
passdb being blanked after the next password change. As a result of that lanman
clients won't be able to authenticate, even if lanman auth is re-enabled later on.
Unlike the encrypt passwords option, this parameter cannot alter client behaviour, and
the LANMAN response will still be sent over the network. See the client lanman auth to
disable this for Samba's clients (such as smbclient)
This parameter is overridden by ntlm auth, so unless that it is also set to
ntlmv1-permitted or yes, then only NTLMv2 logins will be permitted and no LM hash will
be stored. All modern clients support NTLMv2, and but some older clients require
special configuration to use it.
This parameter has no impact on the Samba AD DC, LM authentication is always disabled
and no LM password is ever stored.
Default: lanman auth = no
large readwrite (G)
This parameter determines whether or not smbd(8) supports the new 64k streaming read
and write variant SMB requests introduced with Windows 2000. Note that due to Windows
2000 client redirector bugs this requires Samba to be running on a 64-bit capable
operating system such as IRIX, Solaris or a Linux 2.4 kernel. Can improve performance
by 10% with Windows 2000 clients. Defaults to on. Not as tested as some other Samba
code paths.
Default: large readwrite = yes
ldap admin dn (G)
The ldap admin dn defines the Distinguished Name (DN) name used by Samba to contact
the ldap server when retrieving user account information. The ldap admin dn is used in
conjunction with the admin dn password stored in the private/secrets.tdb file. See the
smbpasswd(8) man page for more information on how to accomplish this.
The ldap admin dn requires a fully specified DN. The ldap suffix is not appended to
the ldap admin dn.
No default
ldap connection timeout (G)
This parameter tells the LDAP library calls which timeout in seconds they should honor
during initial connection establishments to LDAP servers. It is very useful in
failover scenarios in particular. If one or more LDAP servers are not reachable at
all, we do not have to wait until TCP timeouts are over. This feature must be
supported by your LDAP library.
This parameter is different from ldap timeout which affects operations on LDAP servers
using an existing connection and not establishing an initial connection.
Default: ldap connection timeout = 2
ldap debug level (G)
This parameter controls the debug level of the LDAP library calls. In the case of
OpenLDAP, it is the same bit-field as understood by the server and documented in the
slapd.conf(5) manpage. A typical useful value will be 1 for tracing function calls.
The debug output from the LDAP libraries appears with the prefix [LDAP] in Samba's
logging output. The level at which LDAP logging is printed is controlled by the
parameter ldap debug threshold.
Default: ldap debug level = 0
Example: ldap debug level = 1
ldap debug threshold (G)
This parameter controls the Samba debug level at which the ldap library debug output
is printed in the Samba logs. See the description of ldap debug level for details.
Default: ldap debug threshold = 10
Example: ldap debug threshold = 5
ldap delete dn (G)
This parameter specifies whether a delete operation in the ldapsam deletes the
complete entry or only the attributes specific to Samba.
Default: ldap delete dn = no
ldap deref (G)
This option controls whether Samba should tell the LDAP library to use a certain alias
dereferencing method. The default is auto, which means that the default setting of the
ldap client library will be kept. Other possible values are never, finding, searching
and always. Grab your LDAP manual for more information.
Default: ldap deref = auto
Example: ldap deref = searching
ldap follow referral (G)
This option controls whether to follow LDAP referrals or not when searching for
entries in the LDAP database. Possible values are on to enable following referrals,
off to disable this, and auto, to use the libldap default settings. libldap's choice
of following referrals or not is set in /etc/openldap/ldap.conf with the REFERRALS
parameter as documented in ldap.conf(5).
Default: ldap follow referral = auto
Example: ldap follow referral = off
ldap group suffix (G)
This parameter specifies the suffix that is used for groups when these are added to
the LDAP directory. If this parameter is unset, the value of ldap suffix will be used
instead. The suffix string is prepended to the ldap suffix string so use a partial DN.
Default: ldap group suffix =
Example: ldap group suffix = ou=Groups
ldap idmap suffix (G)
This parameters specifies the suffix that is used when storing idmap mappings. If this
parameter is unset, the value of ldap suffix will be used instead. The suffix string
is prepended to the ldap suffix string so use a partial DN.
Default: ldap idmap suffix =
Example: ldap idmap suffix = ou=Idmap
ldap machine suffix (G)
It specifies where machines should be added to the ldap tree. If this parameter is
unset, the value of ldap suffix will be used instead. The suffix string is prepended
to the ldap suffix string so use a partial DN.
Default: ldap machine suffix =
Example: ldap machine suffix = ou=Computers
ldap max anonymous request size (G)
This parameter specifies the maximum permitted size (in bytes) for an LDAP request
received on an anonymous connection.
If the request size exceeds this limit the request will be rejected.
Default: ldap max anonymous request size = 256000
Example: ldap max anonymous request size = 500000
ldap max authenticated request size (G)
This parameter specifies the maximum permitted size (in bytes) for an LDAP request
received on an authenticated connection.
If the request size exceeds this limit the request will be rejected.
Default: ldap max authenticated request size = 16777216
Example: ldap max authenticated request size = 4194304
ldap max search request size (G)
This parameter specifies the maximum permitted size (in bytes) for an LDAP search
request.
If the request size exceeds this limit the request will be rejected.
Default: ldap max search request size = 256000
Example: ldap max search request size = 4194304
ldap page size (G)
This parameter specifies the number of entries per page.
If the LDAP server supports paged results, clients can request subsets of search
results (pages) instead of the entire list. This parameter specifies the size of these
pages.
Default: ldap page size = 1000
Example: ldap page size = 512
ldap password sync
This parameter is a synonym for ldap passwd sync.
ldap passwd sync (G)
This option is used to define whether or not Samba should sync the LDAP password with
the NT and LM hashes for normal accounts (NOT for workstation, server or domain
trusts) on a password change via SAMBA.
The ldap passwd sync can be set to one of three values:
• Yes = Try to update the LDAP, NT and LM passwords and update the pwdLastSet
time.
• No = Update NT and LM passwords and update the pwdLastSet time.
• Only = Only update the LDAP password and let the LDAP server do the rest.
Default: ldap passwd sync = no
ldap replication sleep (G)
When Samba is asked to write to a read-only LDAP replica, we are redirected to talk to
the read-write master server. This server then replicates our changes back to the
'local' server, however the replication might take some seconds, especially over slow
links. Certain client activities, particularly domain joins, can become confused by
the 'success' that does not immediately change the LDAP back-end's data.
This option simply causes Samba to wait a short time, to allow the LDAP server to
catch up. If you have a particularly high-latency network, you may wish to time the
LDAP replication with a network sniffer, and increase this value accordingly. Be aware
that no checking is performed that the data has actually replicated.
The value is specified in milliseconds, the maximum value is 5000 (5 seconds).
Default: ldap replication sleep = 1000
ldapsam:editposix (G)
Editposix is an option that leverages ldapsam:trusted to make it simpler to manage a
domain controller eliminating the need to set up custom scripts to add and manage the
posix users and groups. This option will instead directly manipulate the ldap tree to
create, remove and modify user and group entries. This option also requires a running
winbindd as it is used to allocate new uids/gids on user/group creation. The
allocation range must be therefore configured.
To use this option, a basic ldap tree must be provided and the ldap suffix parameters
must be properly configured. On virgin servers the default users and groups
(Administrator, Guest, Domain Users, Domain Admins, Domain Guests) can be precreated
with the command net sam provision. To run this command the ldap server must be
running, Winbindd must be running and the smb.conf ldap options must be properly
configured. The typical ldap setup used with the ldapsam:trusted = yes option is
usually sufficient to use ldapsam:editposix = yes as well.
An example configuration can be the following:
encrypt passwords = true
passdb backend = ldapsam
ldapsam:trusted=yes
ldapsam:editposix=yes
ldap admin dn = cn=admin,dc=samba,dc=org
ldap delete dn = yes
ldap group suffix = ou=groups
ldap idmap suffix = ou=idmap
ldap machine suffix = ou=computers
ldap user suffix = ou=users
ldap suffix = dc=samba,dc=org
idmap backend = ldap:"ldap://localhost"
idmap uid = 5000-50000
idmap gid = 5000-50000
This configuration assumes a directory layout like described in the following ldif:
dn: dc=samba,dc=org
objectClass: top
objectClass: dcObject
objectClass: organization
o: samba.org
dc: samba
dn: cn=admin,dc=samba,dc=org
objectClass: simpleSecurityObject
objectClass: organizationalRole
cn: admin
description: LDAP administrator
userPassword: secret
dn: ou=users,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: users
dn: ou=groups,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: groups
dn: ou=idmap,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: idmap
dn: ou=computers,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: computers
Default: ldapsam:editposix = no
ldapsam:trusted (G)
By default, Samba as a Domain Controller with an LDAP backend needs to use the
Unix-style NSS subsystem to access user and group information. Due to the way Unix
stores user information in /etc/passwd and /etc/group this inevitably leads to
inefficiencies. One important question a user needs to know is the list of groups he
is member of. The plain UNIX model involves a complete enumeration of the file
/etc/group and its NSS counterparts in LDAP. UNIX has optimized functions to enumerate
group membership. Sadly, other functions that are used to deal with user and group
attributes lack such optimization.
To make Samba scale well in large environments, the ldapsam:trusted = yes option
assumes that the complete user and group database that is relevant to Samba is stored
in LDAP with the standard posixAccount/posixGroup attributes. It further assumes that
the Samba auxiliary object classes are stored together with the POSIX data in the same
LDAP object. If these assumptions are met, ldapsam:trusted = yes can be activated and
Samba can bypass the NSS system to query user group memberships. Optimized LDAP
queries can greatly speed up domain logon and administration tasks. Depending on the
size of the LDAP database a factor of 100 or more for common queries is easily
achieved.
Default: ldapsam:trusted = no
ldap server require strong auth (G)
The ldap server require strong auth defines whether the ldap server requires ldap
traffic to be signed or signed and encrypted (sealed). Possible values are no,
allow_sasl_without_tls_channel_bindings and yes.
Windows has LdapEnforceChannelBinding under
HKLM\SYSTEM\CurrentControlSet\Services\NTDS\Parameters\.
A value of no allows simple and sasl binds over all transports. This matches
LdapEnforceChannelBinding=0.
A value of allow_sasl_without_tls_channel_bindings allows simple and sasl binds
(without sign or seal) over TLS encrypted connections. Missing tls channel bindings
are ignored, so only use this if a value of yes is not possible. Unencrypted
connections only allow sasl binds with sign or seal. This matches
LdapEnforceChannelBinding=1.
Before support for tls channel bindings existed in Samba, a value of
allow_sasl_over_tls was possible in order to allow sasl binds without tls channel
bindings. This now misleading as a value of yes will now allow sasl binds with tls
channel bindings. Configurations should be changed to yes instead or
allow_sasl_without_tls_channel_bindings if really required. Currently
allow_sasl_over_tls is just an alias of allow_sasl_without_tls_channel_bindings, but
it will be removed in future versions.
A value of yes allows only simple binds and sasl binds with correct tls channel
bindings over TLS encrypted connections. sasl binds without tls channel bindings are
not allowed. Unencrypted connections only allow sasl binds with sign or seal. This
matches LdapEnforceChannelBinding=2.
Default: ldap server require strong auth = yes
ldap ssl (G)
This option is used to define whether or not Samba should use SSL when connecting to
the ldap server This is NOT related to Samba's previous SSL support which was enabled
by specifying the --with-ssl option to the configure script.
LDAP connections should be secured where possible. This may be done setting either
this parameter to start tls or by specifying ldaps:// in the URL argument of passdb
backend.
The ldap ssl can be set to one of two values:
• Off = Never use SSL when querying the directory.
• start tls = Use the LDAPv3 StartTLS extended operation (RFC2830) for
communicating with the directory server.
Please note that this parameter does only affect rpc methods.
Default: ldap ssl = start tls
ldap suffix (G)
Specifies the base for all ldap suffixes and for storing the sambaDomain object.
The ldap suffix will be appended to the values specified for the ldap user suffix,
ldap group suffix, ldap machine suffix, and the ldap idmap suffix. Each of these
should be given only a DN relative to the ldap suffix.
Default: ldap suffix =
Example: ldap suffix = dc=samba,dc=org
ldap timeout (G)
This parameter defines the number of seconds that Samba should use as timeout for LDAP
operations.
Default: ldap timeout = 15
ldap user suffix (G)
This parameter specifies where users are added to the tree. If this parameter is
unset, the value of ldap suffix will be used instead. The suffix string is prepended
to the ldap suffix string so use a partial DN.
Default: ldap user suffix =
Example: ldap user suffix = ou=people
level2 oplocks (S)
This parameter controls whether Samba supports level2 (read-only) oplocks on a share.
Level2, or read-only oplocks allow Windows NT clients that have an oplock on a file to
downgrade from a read-write oplock to a read-only oplock once a second client opens
the file (instead of releasing all oplocks on a second open, as in traditional,
exclusive oplocks). This allows all openers of the file that support level2 oplocks to
cache the file for read-ahead only (ie. they may not cache writes or lock requests)
and increases performance for many accesses of files that are not commonly written
(such as application .EXE files).
Once one of the clients which have a read-only oplock writes to the file all clients
are notified (no reply is needed or waited for) and told to break their oplocks to
"none" and delete any read-ahead caches.
It is recommended that this parameter be turned on to speed access to shared
executables.
For more discussions on level2 oplocks see the CIFS spec.
Currently, if kernel oplocks are supported then level2 oplocks are not granted (even
if this parameter is set to yes). Note also, the oplocks parameter must be set to yes
on this share in order for this parameter to have any effect.
Default: level2 oplocks = yes
lm announce (G)
This parameter determines if nmbd(8) will produce Lanman announce broadcasts that are
needed by OS/2 clients in order for them to see the Samba server in their browse list.
This parameter can have three values, yes, no, or auto. The default is auto. If set to
no Samba will never produce these broadcasts. If set to yes Samba will produce Lanman
announce broadcasts at a frequency set by the parameter lm interval. If set to auto
Samba will not send Lanman announce broadcasts by default but will listen for them. If
it hears such a broadcast on the wire it will then start sending them at a frequency
set by the parameter lm interval.
Default: lm announce = auto
Example: lm announce = yes
lm interval (G)
If Samba is set to produce Lanman announce broadcasts needed by OS/2 clients (see the
lm announce parameter) then this parameter defines the frequency in seconds with which
they will be made. If this is set to zero then no Lanman announcements will be made
despite the setting of the lm announce parameter.
Default: lm interval = 60
Example: lm interval = 120
load printers (G)
A boolean variable that controls whether all printers in the printcap will be loaded
for browsing by default. See the printers section for more details.
Default: load printers = yes
local master (G)
This option allows nmbd(8) to try and become a local master browser on a subnet. If
set to no then nmbd will not attempt to become a local master browser on a subnet and
will also lose in all browsing elections. By default this value is set to yes. Setting
this value to yes doesn't mean that Samba will become the local master browser on a
subnet, just that nmbd will participate in elections for local master browser.
Setting this value to no will cause nmbd never to become a local master browser.
Default: local master = yes
lock dir
This parameter is a synonym for lock directory.
lock directory (G)
This option specifies the directory where lock files will be placed. The lock files
are used to implement the max connections option.
Note: This option can not be set inside registry configurations.
The files placed in this directory are not required across service restarts and can be
safely placed on volatile storage (e.g. tmpfs in Linux)
Default: lock directory = /run/samba
Example: lock directory = /var/run/samba/locks
locking (S)
This controls whether or not locking will be performed by the server in response to
lock requests from the client.
If locking = no, all lock and unlock requests will appear to succeed and all lock
queries will report that the file in question is available for locking.
If locking = yes, real locking will be performed by the server.
This option may be useful for read-only filesystems which may not need locking (such
as CDROM drives), although setting this parameter of no is not really recommended even
in this case.
Be careful about disabling locking either globally or in a specific service, as lack
of locking may result in data corruption. You should never need to set this parameter.
Default: locking = yes
lock spin time (G)
The time in milliseconds that smbd should keep waiting to see if a failed lock request
can be granted. This parameter has changed in default value from Samba 3.0.23 from 10
to 200. The associated lock spin count parameter is no longer used in Samba 3.0.24.
You should not need to change the value of this parameter.
Default: lock spin time = 200
log file (G)
This option allows you to override the name of the Samba log file (also known as the
debug file).
This option takes the standard substitutions, allowing you to have separate log files
for each user or machine.
No default
Example: log file = /usr/local/samba/var/log.%m
logging (G)
This parameter configures logging backends. Multiple backends can be specified at the
same time, with different log levels for each backend. The parameter is a list of
backends, where each backend is specified as backend[:option][@loglevel].
The 'option' parameter can be used to pass backend-specific options.
The log level for a backend is optional, if it is not set for a backend, all messages
are sent to this backend. The parameter log level determines overall log levels, while
the log levels specified here define what is sent to the individual backends.
When logging is set, it overrides the syslog and syslog only parameters.
Some backends are only available when Samba has been compiled with the additional
libraries. The overall list of logging backends:
• syslog
• file
• systemd
• lttng
• gpfs
• ringbuf
The ringbuf backend supports an optional size argument to change the buffer size used,
the default is 1 MB: ringbuf:size=NBYTES
Default: logging =
Example: logging = syslog@1 file
debuglevel
This parameter is a synonym for log level.
log level (G)
The value of the parameter (a string) allows the debug level (logging level) to be
specified in the smb.conf file.
This parameter has been extended since the 2.2.x series, now it allows one to specify
the debug level for multiple debug classes and distinct logfiles for debug classes.
This is to give greater flexibility in the configuration of the system. The following
debug classes are currently implemented:
• all
• tdb
• printdrivers
• lanman
• smb
• rpc_parse
• rpc_srv
• rpc_cli
• passdb
• sam
• auth
• winbind
• vfs
• idmap
• quota
• acls
• locking
• msdfs
• dmapi
• registry
• scavenger
• dns
• ldb
• tevent
• auth_audit
• auth_json_audit
• kerberos
• drs_repl
• smb2
• smb2_credits
• dsdb_audit
• dsdb_json_audit
• dsdb_password_audit
• dsdb_password_json_audit
• dsdb_transaction_audit
• dsdb_transaction_json_audit
• dsdb_group_audit
• dsdb_group_json_audit
Various modules register dynamic debug classes at first usage:
• catia
• dfs_samba4
• extd_audit
• fileid
• fruit
• full_audit
• media_harmony
• preopen
• recycle
• shadow_copy
• shadow_copy
• unityed_media
• virusfilter
To configure the logging for specific classes to go into a different file then log
file, you can append @PATH to the class, eg log level = 1
full_audit:1@/var/log/audit.log.
Authentication and authorization audit information is logged under the auth_audit, and
if Samba was not compiled with --without-json, a JSON representation is logged under
auth_json_audit.
Support is comprehensive for all authentication and authorisation of user accounts in
the Samba Active Directory Domain Controller, as well as the implicit authentication
in password changes. In the file server, NTLM authentication, SMB and RPC
authorization is covered.
Log levels for auth_audit and auth_audit_json are:
• 2: Authentication Failure
• 3: Authentication Success
• 4: Authorization Success
• 5: Anonymous Authentication and Authorization Success
Changes to the AD DC sam.ldb database are logged under the dsdb_audit and a JSON
representation is logged under dsdb_json_audit.
Group membership changes to the AD DC sam.ldb database are logged under the
dsdb_group_audit and a JSON representation is logged under dsdb_group_json_audit.
Log levels for dsdb_audit, dsdb_json_audit, dsdb_group_audit, dsdb_group_json_audit
and dsdb_json_audit are:
• 5: Database modifications
• 5: Replicated updates from another DC
Password changes and Password resets in the AD DC are logged under dsdb_password_audit
and a JSON representation is logged under the dsdb_password_json_audit. Password
changes will also appears as authentication events via auth_audit and auth_audit_json.
Log levels for dsdb_password_audit and dsdb_password_json_audit are:
• 5: Successful password changes and resets
Transaction rollbacks and prepare commit failures are logged under the
dsdb_transaction_audit and a JSON representation is logged under the
dsdb_transaction_json_audit.
Log levels for dsdb_transaction_audit and dsdb_transaction_json are:
• 5: Transaction failure (rollback)
• 10: Transaction success (commit)
Transaction roll-backs are possible in Samba, and whilst they rarely reflect anything
more than the failure of an individual operation (say due to the add of a conflicting
record), they are possible. Audit logs are already generated and sent to the system
logs before the transaction is complete. Logging the transaction details allows the
identification of password and sam.ldb operations that have been rolled back, and so
have not actually persisted.
Warning
Changes to sam.ldb made locally by the root user with direct access to the
database are not logged to the system logs, but to the administrator's own
console. While less than ideal, any user able to make such modifications could
disable the audit logging in any case.
Default: log level = 0
Example: log level = 3 passdb:5 auth:10 winbind:2
Example: log level = 1 full_audit:1@/var/log/audit.log winbind:2
log nt token command (G)
This option can be set to a command that will be called when new nt tokens are
created.
This is only useful for development purposes.
Default: log nt token command =
logon drive (G)
This parameter specifies the local path to which the home directory will be connected
(see logon home) and is only used by NT Workstations.
Note that this option is only useful if Samba is set up as a logon server.
Default: logon drive =
Example: logon drive = h:
logon home (G)
This parameter specifies the home directory location when a Win95/98 or NT Workstation
logs into a Samba PDC. It allows you to do
C:\>NET USE H: /HOME
from a command prompt, for example.
This option takes the standard substitutions, allowing you to have separate logon
scripts for each user or machine.
This parameter can be used with Win9X workstations to ensure that roaming profiles are
stored in a subdirectory of the user's home directory. This is done in the following
way:
logon home = \\%N\%U\profile
This tells Samba to return the above string, with substitutions made when a client
requests the info, generally in a NetUserGetInfo request. Win9X clients truncate the
info to \\server\share when a user does net use /home but use the whole string when
dealing with profiles.
Note that in prior versions of Samba, the logon path was returned rather than logon
home. This broke net use /home but allowed profiles outside the home directory. The
current implementation is correct, and can be used for profiles if you use the above
trick.
Disable this feature by setting logon home = "" - using the empty string.
This option is only useful if Samba is set up as a logon server.
Default: logon home = \\%N\%U
Example: logon home = \\remote_smb_server\%U
logon path (G)
This parameter specifies the directory where roaming profiles (Desktop, NTuser.dat,
etc) are stored. Contrary to previous versions of these manual pages, it has nothing
to do with Win 9X roaming profiles. To find out how to handle roaming profiles for Win
9X system, see the logon home parameter.
This option takes the standard substitutions, allowing you to have separate logon
scripts for each user or machine. It also specifies the directory from which the
"Application Data", desktop, start menu, network neighborhood, programs and other
folders, and their contents, are loaded and displayed on your Windows NT client.
The share and the path must be readable by the user for the preferences and
directories to be loaded onto the Windows NT client. The share must be writeable when
the user logs in for the first time, in order that the Windows NT client can create
the NTuser.dat and other directories. Thereafter, the directories and any of the
contents can, if required, be made read-only. It is not advisable that the NTuser.dat
file be made read-only - rename it to NTuser.man to achieve the desired effect (a
MANdatory profile).
Windows clients can sometimes maintain a connection to the [homes] share, even though
there is no user logged in. Therefore, it is vital that the logon path does not
include a reference to the homes share (i.e. setting this parameter to
\\%N\homes\profile_path will cause problems).
This option takes the standard substitutions, allowing you to have separate logon
scripts for each user or machine.
Warning
Do not quote the value. Setting this as “\\%N\profile\%U” will break profile
handling. Where the tdbsam or ldapsam passdb backend is used, at the time the user
account is created the value configured for this parameter is written to the
passdb backend and that value will over-ride the parameter value present in the
smb.conf file. Any error present in the passdb backend account record must be
edited using the appropriate tool (pdbedit on the command-line, or any other
locally provided system tool).
Note that this option is only useful if Samba is set up as a domain controller.
Disable the use of roaming profiles by setting the value of this parameter to the
empty string. For example, logon path = "". Take note that even if the default setting
in the smb.conf file is the empty string, any value specified in the user account
settings in the passdb backend will over-ride the effect of setting this parameter to
null. Disabling of all roaming profile use requires that the user account settings
must also be blank.
An example of use is:
logon path = \\PROFILESERVER\PROFILE\%U
Default: logon path = \\%N\%U\profile
logon script (G)
This parameter specifies the batch file (.bat) or NT command file (.cmd) to be
downloaded and run on a machine when a user successfully logs in. The file must
contain the DOS style CR/LF line endings. Using a DOS-style editor to create the file
is recommended.
The script must be a relative path to the [netlogon] service. If the [netlogon]
service specifies a path of /usr/local/samba/netlogon, and logon script = STARTUP.BAT,
then the file that will be downloaded is:
/usr/local/samba/netlogon/STARTUP.BAT
The contents of the batch file are entirely your choice. A suggested command would be
to add NET TIME \\SERVER /SET /YES, to force every machine to synchronize clocks with
the same time server. Another use would be to add NET USE U: \\SERVER\UTILS for
commonly used utilities, or
NET USE Q: \\SERVER\ISO9001_QA
for example.
Note that it is particularly important not to allow write access to the [netlogon]
share, or to grant users write permission on the batch files in a secure environment,
as this would allow the batch files to be arbitrarily modified and security to be
breached.
This option takes the standard substitutions, allowing you to have separate logon
scripts for each user or machine.
This option is only useful if Samba is set up as a logon server in a classic domain
controller role. If Samba is set up as an Active Directory domain controller, LDAP
attribute scriptPath is used instead. For configurations where passdb backend =
ldapsam is in use, this option only defines a default value in case LDAP attribute
sambaLogonScript is missing.
Default: logon script =
Example: logon script = scripts\%U.bat
log writeable files on exit (G)
When the network connection between a CIFS client and Samba dies, Samba has no option
but to simply shut down the server side of the network connection. If this happens,
there is a risk of data corruption because the Windows client did not complete all
write operations that the Windows application requested. Setting this option to "yes"
makes smbd log with a level 0 message a list of all files that have been opened for
writing when the network connection died. Those are the files that are potentially
corrupted. It is meant as an aid for the administrator to give him a list of files to
do consistency checks on.
Default: log writeable files on exit = no
lppause command (S)
This parameter specifies the command to be executed on the server host in order to
stop printing or spooling a specific print job.
This command should be a program or script which takes a printer name and job number
to pause the print job. One way of implementing this is by using job priorities, where
jobs having a too low priority won't be sent to the printer.
If a %p is given then the printer name is put in its place. A %j is replaced with the
job number (an integer). On HPUX (see printing=hpux ), if the -p%p option is added to
the lpq command, the job will show up with the correct status, i.e. if the job
priority is lower than the set fence priority it will have the PAUSED status, whereas
if the priority is equal or higher it will have the SPOOLED or PRINTING status.
Note that it is good practice to include the absolute path in the lppause command as
the PATH may not be available to the server.
Currently no default value is given to this string, unless the value of the printing
parameter is SYSV, in which case the default is : lp -i %p-%j -H hold or if the value
of the printing parameter is SOFTQ, then the default is: qstat -s -j%j -h.
Default: lppause command = # determined by printing parameter
Example: lppause command = /usr/bin/lpalt %p-%j -p0
lpq cache time (G)
This controls how long lpq info will be cached for to prevent the lpq command being
called too often. A separate cache is kept for each variation of the lpq command used
by the system, so if you use different lpq commands for different users then they
won't share cache information.
The cache files are stored in /tmp/lpq.xxxx where xxxx is a hash of the lpq command in
use.
The default is 30 seconds, meaning that the cached results of a previous identical lpq
command will be used if the cached data is less than 30 seconds old. A large value may
be advisable if your lpq command is very slow.
A value of 0 will disable caching completely.
Default: lpq cache time = 30
Example: lpq cache time = 10
lpq command (S)
This parameter specifies the command to be executed on the server host in order to
obtain lpq-style printer status information.
This command should be a program or script which takes a printer name as its only
parameter and outputs printer status information.
Currently nine styles of printer status information are supported; BSD, AIX, LPRNG,
PLP, SYSV, HPUX, QNX, CUPS, and SOFTQ. This covers most UNIX systems. You control
which type is expected using the printing = option.
Some clients (notably Windows for Workgroups) may not correctly send the connection
number for the printer they are requesting status information about. To get around
this, the server reports on the first printer service connected to by the client. This
only happens if the connection number sent is invalid.
If a %p is given then the printer name is put in its place. Otherwise it is placed at
the end of the command.
Note that it is good practice to include the absolute path in the lpq command as the
$PATH may not be available to the server. When compiled with the CUPS libraries, no
lpq command is needed because smbd will make a library call to obtain the print queue
listing.
Default: lpq command = # determined by printing parameter
Example: lpq command = /usr/bin/lpq -P%p
lpresume command (S)
This parameter specifies the command to be executed on the server host in order to
restart or continue printing or spooling a specific print job.
This command should be a program or script which takes a printer name and job number
to resume the print job. See also the lppause command parameter.
If a %p is given then the printer name is put in its place. A %j is replaced with the
job number (an integer).
Note that it is good practice to include the absolute path in the lpresume command as
the PATH may not be available to the server.
See also the printing parameter.
Default: Currently no default value is given to this string, unless the value of the
printing parameter is SYSV, in which case the default is:
lp -i %p-%j -H resume
or if the value of the printing parameter is SOFTQ, then the default is:
qstat -s -j%j -r
Default: lpresume command = # determined by printing parameter
Example: lpresume command = /usr/bin/lpalt %p-%j -p2
lprm command (S)
This parameter specifies the command to be executed on the server host in order to
delete a print job.
This command should be a program or script which takes a printer name and job number,
and deletes the print job.
If a %p is given then the printer name is put in its place. A %j is replaced with the
job number (an integer).
Note that it is good practice to include the absolute path in the lprm command as the
PATH may not be available to the server.
Examples of use are:
lprm command = /usr/bin/lprm -P%p %j
or
lprm command = /usr/bin/cancel %p-%j
Default: lprm command = # determined by printing parameter
lsa over netlogon (G)
Setting this deprecated option will allow the RPC server in the AD DC to answer the
LSARPC interface on the \pipe\netlogon IPC pipe.
When enabled, this matches the behaviour of Microsoft's Windows, due to their internal
implementation choices.
If it is disabled (the default), the AD DC can offer improved performance, as the
netlogon server is decoupled and can run as multiple processes.
Default: lsa over netlogon = no
machine password timeout (G)
If a Samba server is a member of a Windows NT or Active Directory Domain (see the
security = domain and security = ads parameters), then periodically a running winbindd
process will try and change the MACHINE ACCOUNT PASSWORD stored in the TDB called
secrets.tdb. This parameter specifies how often this password will be changed, in
seconds. The default is one week (expressed in seconds), the same as a Windows NT
Domain member server.
See also smbpasswd(8), and the security = domain and security = ads parameters.
Default: machine password timeout = 604800
magic output (S)
This parameter specifies the name of a file which will contain output created by a
magic script (see the magic script parameter below).
Warning
If two clients use the same magic script in the same directory the output file
content is undefined.
Default: magic output = # <magic script name>.out
Example: magic output = myfile.txt
magic script (S)
This parameter specifies the name of a file which, if opened, will be executed by the
server when the file is closed. This allows a UNIX script to be sent to the Samba host
and executed on behalf of the connected user.
Scripts executed in this way will be deleted upon completion assuming that the user
has the appropriate level of privilege and the file permissions allow the deletion.
If the script generates output, output will be sent to the file specified by the magic
output parameter (see above).
Note that some shells are unable to interpret scripts containing CR/LF instead of CR
as the end-of-line marker. Magic scripts must be executable as is on the host, which
for some hosts and some shells will require filtering at the DOS end.
Magic scripts are EXPERIMENTAL and should NOT be relied upon.
Default: magic script =
Example: magic script = user.csh
mangled names (S)
This controls whether non-DOS names under UNIX should be mapped to DOS-compatible
names ("mangled") and made visible, or whether non-DOS names should simply be ignored.
See the section on name mangling for details on how to control the mangling process.
Possible option settings are
• yes - enables name mangling for all not DOS 8.3 conforming names.
• no - disables any name mangling.
• illegal (default) - does mangling for names with illegal NTFS characters.
This is the most sensible setting for modern clients that don't use the
shortname anymore.
If mangling is used then the mangling method is as follows:
• The first (up to) five alphanumeric characters before the rightmost dot of
the filename are preserved, forced to upper case, and appear as the first
(up to) five characters of the mangled name.
• A tilde "~" is appended to the first part of the mangled name, followed by
a two-character unique sequence, based on the original root name (i.e., the
original filename minus its final extension). The final extension is
included in the hash calculation only if it contains any upper case
characters or is longer than three characters.
Note that the character to use may be specified using the mangling char
option, if you don't like '~'.
• Files whose UNIX name begins with a dot will be presented as DOS hidden
files. The mangled name will be created as for other filenames, but with
the leading dot removed and "___" as its extension regardless of actual
original extension (that's three underscores).
The two-digit hash value consists of upper case alphanumeric characters.
This algorithm can cause name collisions only if files in a directory share the same
first five alphanumeric characters. The probability of such a clash is 1/1300.
The name mangling (if enabled) allows a file to be copied between UNIX directories
from Windows/DOS while retaining the long UNIX filename. UNIX files can be renamed to
a new extension from Windows/DOS and will retain the same basename. Mangled names do
not change between sessions.
Default: mangled names = illegal
Example: mangled names = no
mangle prefix (G)
controls the number of prefix characters from the original name used when generating
the mangled names. A larger value will give a weaker hash and therefore more name
collisions. The minimum value is 1 and the maximum value is 6.
mangle prefix is effective only when mangling method is hash2.
Default: mangle prefix = 1
Example: mangle prefix = 4
mangling char (S)
This controls what character is used as the magic character in name mangling. The
default is a '~' but this may interfere with some software. Use this option to set it
to whatever you prefer. This is effective only when mangling method is hash.
Default: mangling char = ~
Example: mangling char = ^
mangling method (G)
controls the algorithm used for the generating the mangled names. Can take two
different values, "hash" and "hash2". "hash" is the algorithm that was used in Samba
for many years and was the default in Samba 2.2.x "hash2" is now the default and is
newer and considered a better algorithm (generates less collisions) in the names. Many
Win32 applications store the mangled names and so changing to algorithms must not be
done lightly as these applications may break unless reinstalled.
Default: mangling method = hash2
Example: mangling method = hash
map acl inherit (S)
This boolean parameter is only relevant for systems that do not support standardized
NFS4 ACLs but only a POSIX draft implementation of ACLs. Linux is the only common UNIX
system which does still not offer standardized NFS4 ACLs actually. On such systems
this parameter controls whether smbd(8) will attempt to map the 'protected' (don't
inherit) flags of the Windows ACLs into an extended attribute called user.SAMBA_PAI
(POSIX draft ACL Inheritance). This parameter requires support for extended attributes
on the filesystem and allows the Windows ACL editor to store (non-)inheritance
information while NT ACLs are mapped best-effort to the POSIX draft ACLs that the OS
and filesystem implements.
Default: map acl inherit = no
map archive (S)
This controls whether the DOS archive attribute should be mapped to the UNIX owner
execute bit. The DOS archive bit is set when a file has been modified since its last
backup. One motivation for this option is to keep Samba/your PC from making any file
it touches from becoming executable under UNIX. This can be quite annoying for shared
source code, documents, etc...
Note that this parameter will be ignored if the store dos attributes parameter is set,
as the DOS archive attribute will then be stored inside a UNIX extended attribute.
Note that this requires the create mask parameter to be set such that owner execute
bit is not masked out (i.e. it must include 100). See the parameter create mask for
details.
Default: map archive = yes
map hidden (S)
This controls whether DOS style hidden files should be mapped to the UNIX world
execute bit.
Note that this parameter will be ignored if the store dos attributes parameter is set,
as the DOS hidden attribute will then be stored inside a UNIX extended attribute.
Note that this requires the create mask to be set such that the world execute bit is
not masked out (i.e. it must include 001). See the parameter create mask for details.
Default: map hidden = no
map readonly (S)
This controls how the DOS read only attribute should be mapped from a UNIX filesystem.
This parameter can take three different values, which tell smbd(8) how to display the
read only attribute on files, where either store dos attributes is set to No, or no
extended attribute is present. If store dos attributes is set to yes then this
parameter is ignored. This is a new parameter introduced in Samba version 3.0.21.
The three settings are :
• Yes - The read only DOS attribute is mapped to the inverse of the user or
owner write bit in the unix permission mode set. If the owner write bit is
not set, the read only attribute is reported as being set on the file. If
the read only DOS attribute is set, Samba sets the owner, group and others
write bits to zero. Write bits set in an ACL are ignored by Samba. If the
read only DOS attribute is unset, Samba simply sets the write bit of the
owner to one.
• Permissions - The read only DOS attribute is mapped to the effective
permissions of the connecting user, as evaluated by smbd(8) by reading the
unix permissions and filesystem ACL (if present). If the connecting user
does not have permission to modify the file, the read only attribute is
reported as being set on the file.
• No - The read only DOS attribute is unaffected by permissions, and can only
be set by the store dos attributes method. This may be useful for exporting
mounted CDs.
Note that this parameter will be ignored if the store dos attributes parameter is set,
as the DOS 'read-only' attribute will then be stored inside a UNIX extended attribute.
The default has changed to no in Samba release 4.9.0 and above to allow better Windows
fileserver compatibility in a default install. In addition the default setting of
store dos attributes has been changed to Yes in Samba release 4.9.0 and above.
Default: map readonly = no
map system (S)
This controls whether DOS style system files should be mapped to the UNIX group
execute bit.
Note that this parameter will be ignored if the store dos attributes parameter is set,
as the DOS system attribute will then be stored inside a UNIX extended attribute.
Note that this requires the create mask to be set such that the group execute bit is
not masked out (i.e. it must include 010). See the parameter create mask for details.
Default: map system = no
map to guest (G)
This parameter can take four different values, which tell smbd(8) what to do with user
login requests that don't match a valid UNIX user in some way.
The four settings are :
• Never - Means user login requests with an invalid password are rejected.
This is the default.
• Bad User - Means user logins with an invalid password are rejected, unless
the username does not exist, in which case it is treated as a guest login
and mapped into the guest account.
• Bad Password - Means user logins with an invalid password are treated as a
guest login and mapped into the guest account. Note that this can cause
problems as it means that any user incorrectly typing their password will
be silently logged on as "guest" - and will not know the reason they cannot
access files they think they should - there will have been no message given
to them that they got their password wrong. Helpdesk services will hate you
if you set the map to guest parameter this way :-).
• Bad Uid - Is only applicable when Samba is configured in some type of
domain mode security (security = {domain|ads}) and means that user logins
which are successfully authenticated but which have no valid Unix user
account (and smbd is unable to create one) should be mapped to the defined
guest account. This was the default behavior of Samba 2.x releases. Note
that if a member server is running winbindd, this option should never be
required because the nss_winbind library will export the Windows domain
users and groups to the underlying OS via the Name Service Switch
interface.
Note that this parameter is needed to set up "Guest" share services. This is because
in these modes the name of the resource being requested is not sent to the server
until after the server has successfully authenticated the client so the server cannot
make authentication decisions at the correct time (connection to the share) for
"Guest" shares.
Default: map to guest = Never
Example: map to guest = Bad User
max connections (S)
This option allows the number of simultaneous connections to a service to be limited.
If max connections is greater than 0 then connections will be refused if this number
of connections to the service are already open. A value of zero mean an unlimited
number of connections may be made.
Record lock files are used to implement this feature. The lock files will be stored in
the directory specified by the lock directory option.
Default: max connections = 0
Example: max connections = 10
max disk size (G)
This option allows you to put an upper limit on the apparent size of disks. If you set
this option to 100 then all shares will appear to be not larger than 100 MB in size.
Note that this option does not limit the amount of data you can put on the disk. In
the above case you could still store much more than 100 MB on the disk, but if a
client ever asks for the amount of free disk space or the total disk size then the
result will be bounded by the amount specified in max disk size.
This option is primarily useful to work around bugs in some pieces of software that
can't handle very large disks, particularly disks over 1GB in size.
A max disk size of 0 means no limit.
Default: max disk size = 0
Example: max disk size = 1000
max log size (G)
This option (an integer in kilobytes) specifies the max size the log file should grow
to. Samba periodically checks the size and if it is exceeded it will rename the file,
adding a .old extension.
A size of 0 means no limit.
Default: max log size = 5000
Example: max log size = 1000
max mux (G)
This option controls the maximum number of outstanding simultaneous SMB operations
that Samba tells the client it will allow. You should never need to set this
parameter.
Default: max mux = 50
max open files (G)
This parameter limits the maximum number of open files that one smbd(8) file serving
process may have open for a client at any one time. This parameter can be set very
high (16384) as Samba uses only one bit per unopened file. Setting this parameter
lower than 16384 will cause Samba to complain and set this value back to the minimum
of 16384, as Windows 7 depends on this number of open file handles being available.
The limit of the number of open files is usually set by the UNIX per-process file
descriptor limit rather than this parameter so you should never need to touch this
parameter.
Default: max open files = 16384
max print jobs (S)
This parameter limits the maximum number of jobs allowable in a Samba printer queue at
any given moment. If this number is exceeded, smbd(8) will remote "Out of Space" to
the client.
Default: max print jobs = 1000
Example: max print jobs = 5000
max reported print jobs (S)
This parameter limits the maximum number of jobs displayed in a port monitor for Samba
printer queue at any given moment. If this number is exceeded, the excess jobs will
not be shown. A value of zero means there is no limit on the number of print jobs
reported.
Default: max reported print jobs = 0
Example: max reported print jobs = 1000
max smbd processes (G)
This parameter limits the maximum number of smbd(8) processes concurrently running on
a system and is intended as a stopgap to prevent degrading service to clients in the
event that the server has insufficient resources to handle more than this number of
connections. Remember that under normal operating conditions, each user will have an
smbd(8) associated with him or her to handle connections to all shares from a given
host.
For a Samba ADDC running the standard process model this option limits the number of
processes forked to handle requests. Currently new processes are only forked for ldap
and netlogon requests.
Default: max smbd processes = 0
Example: max smbd processes = 1000
max stat cache size (G)
This parameter limits the size in memory of any stat cache being used to speed up case
insensitive name mappings. It represents the number of kilobyte (1024) units the stat
cache can use. A value of zero, meaning unlimited, is not advisable due to increased
memory usage. You should not need to change this parameter.
Default: max stat cache size = 512
Example: max stat cache size = 100
max ttl (G)
This option tells nmbd(8) what the default 'time to live' of NetBIOS names should be
(in seconds) when nmbd is requesting a name using either a broadcast packet or from a
WINS server. You should never need to change this parameter. The default is 3 days.
Default: max ttl = 259200
max wins ttl (G)
This option tells smbd(8) when acting as a WINS server (wins support = yes) what the
maximum 'time to live' of NetBIOS names that nmbd will grant will be (in seconds). You
should never need to change this parameter. The default is 6 days (518400 seconds).
Default: max wins ttl = 518400
max xmit (G)
This option controls the maximum packet size that will be negotiated by Samba's
smbd(8) for the SMB1 protocol. The default is 16644, which matches the behavior of
Windows 2000. A value below 2048 is likely to cause problems. You should never need to
change this parameter from its default value.
Default: max xmit = 16644
Example: max xmit = 8192
mdns name (G)
This parameter controls the name that multicast DNS support advertises as its'
hostname.
The default is to use the NETBIOS name which is typically the hostname in all capital
letters.
A setting of mdns will defer the hostname configuration to the MDNS library that is
used.
Default: mdns name = netbios
message command (G)
This specifies what command to run when the server receives a WinPopup style message.
This would normally be a command that would deliver the message somehow. How this is
to be done is up to your imagination.
An example is:
message command = csh -c 'xedit %s;rm %s' &
This delivers the message using xedit, then removes it afterwards. NOTE THAT IT IS
VERY IMPORTANT THAT THIS COMMAND RETURN IMMEDIATELY. That's why I have the '&' on the
end. If it doesn't return immediately then your PCs may freeze when sending messages
(they should recover after 30 seconds, hopefully).
All messages are delivered as the global guest user. The command takes the standard
substitutions, although
%u won't work (%U may be better in this case).
Apart from the standard substitutions, some additional ones apply. In particular:
• %s = the filename containing the message.
• %t = the destination that the message was sent to (probably the server
name).
• %f = who the message is from.
You could make this command send mail, or whatever else takes your fancy. Please let
us know of any really interesting ideas you have.
Here's a way of sending the messages as mail to root:
message command = /bin/mail -s 'message from %f on %m' root < %s; rm %s
If you don't have a message command then the message won't be delivered and Samba will
tell the sender there was an error. Unfortunately WfWg totally ignores the error code
and carries on regardless, saying that the message was delivered.
If you want to silently delete it then try:
message command = rm %s
Default: message command =
Example: message command = csh -c 'xedit %s; rm %s' &
min domain uid (G)
The integer parameter specifies the minimum uid allowed when mapping a local account
to a domain account.
Note that this option interacts with the configured idmap ranges!
Default: min domain uid = 1000
min print space (S)
This sets the minimum amount of free disk space that must be available before a user
will be able to spool a print job. It is specified in kilobytes. The default is 0,
which means a user can always spool a print job.
Default: min print space = 0
Example: min print space = 2000
min receivefile size (G)
This option changes the behavior of smbd(8) when processing SMBwriteX calls. Any
incoming SMBwriteX call on a non-signed SMB/CIFS connection greater than this value
will not be processed in the normal way but will be passed to any underlying kernel
recvfile or splice system call (if there is no such call Samba will emulate in user
space). This allows zero-copy writes directly from network socket buffers into the
filesystem buffer cache, if available. It may improve performance but user testing is
recommended. If set to zero Samba processes SMBwriteX calls in the normal way. To
enable POSIX large write support (SMB/CIFS writes up to 16Mb) this option must be
nonzero. The maximum value is 128k. Values greater than 128k will be silently set to
128k.
Note this option will have NO EFFECT if set on a SMB signed connection.
The default is zero, which disables this option.
Default: min receivefile size = 0
min wins ttl (G)
This option tells nmbd(8) when acting as a WINS server (wins support = yes) what the
minimum 'time to live' of NetBIOS names that nmbd will grant will be (in seconds). You
should never need to change this parameter. The default is 6 hours (21600 seconds).
Default: min wins ttl = 21600
mit kdc command (G)
This option specifies the path to the MIT kdc binary.
If the KDC is not installed in the default location and wasn't correctly detected
during build then you should modify this variable and point it to the correct binary.
Default: mit kdc command =
Example: mit kdc command = /opt/mit/sbin/krb5kdc
msdfs proxy (S)
This parameter indicates that the share is a stand-in for another CIFS share whose
location is specified by the value of the parameter. When clients attempt to connect
to this share, they are redirected to one or multiple, comma separated proxied shares
using the SMB-Dfs protocol.
Only Dfs roots can act as proxy shares. Take a look at the msdfs root and host msdfs
options to find out how to set up a Dfs root share.
No default
Example: msdfs proxy = \otherserver\someshare,\otherserver2\someshare
msdfs root (S)
If set to yes, Samba treats the share as a Dfs root and allows clients to browse the
distributed file system tree rooted at the share directory. Dfs links are specified in
the share directory by symbolic links of the form
msdfs:serverA\\shareA,serverB\\shareB and so on. For more information on setting up a
Dfs tree on Samba, refer to the MSDFS chapter in the Samba3-HOWTO book.
Default: msdfs root = no
msdfs shuffle referrals (S)
If set to yes, Samba will shuffle Dfs referrals for a given Dfs link if multiple are
available, allowing for load balancing across clients. For more information on setting
up a Dfs tree on Samba, refer to the MSDFS chapter in the Samba3-HOWTO book.
Default: msdfs shuffle referrals = no
multicast dns register (G)
If compiled with proper support for it, Samba will announce itself with multicast DNS
services like for example provided by the Avahi daemon.
This parameter allows disabling Samba to register itself.
Default: multicast dns register = yes
name cache timeout (G)
Specifies the number of seconds it takes before entries in samba's hostname resolve
cache time out. If the timeout is set to 0. the caching is disabled.
Default: name cache timeout = 660
Example: name cache timeout = 0
name resolve order (G)
This option is used by the programs in the Samba suite to determine what naming
services to use and in what order to resolve host names to IP addresses. Its main
purpose to is to control how netbios name resolution is performed. The option takes a
space separated string of name resolution options.
The options are: "lmhosts", "host", "wins" and "bcast". They cause names to be
resolved as follows:
• lmhosts : Lookup an IP address in the Samba lmhosts file. If the line in
lmhosts has no name type attached to the NetBIOS name (see the manpage for
lmhosts for details) then any name type matches for lookup.
• host : Do a standard host name to IP address resolution, using the system
/etc/hosts or DNS lookups. This method of name resolution is operating
system depended for instance on IRIX or Solaris this may be controlled by
the /etc/nsswitch.conf file. Note that this method is used only if the
NetBIOS name type being queried is the 0x20 (server) name type or 0x1c
(domain controllers). The latter case is only useful for active directory
domains and results in a DNS query for the SRV RR entry matching
_ldap._tcp.domain.
• wins : Query a name with the IP address listed in the WINSSERVER parameter.
If no WINS server has been specified this method will be ignored.
• bcast : Do a broadcast on each of the known local interfaces listed in the
interfaces parameter. This is the least reliable of the name resolution
methods as it depends on the target host being on a locally connected
subnet.
The example below will cause the local lmhosts file to be examined first, followed by
a broadcast attempt, followed by a normal system hostname lookup.
When Samba is functioning in ADS security mode (security = ads) it is advised to use
following settings for name resolve order:
name resolve order = wins bcast
DC lookups will still be done via DNS, but fallbacks to netbios names will not
inundate your DNS servers with needless queries for DOMAIN<0x1c> lookups.
Default: name resolve order = lmhosts wins host bcast
Example: name resolve order = lmhosts bcast host
socket address
This parameter is a synonym for nbt client socket address.
nbt client socket address (G)
This option allows you to control what address Samba will send NBT client packets
from, and process replies using, including in nmbd.
Setting this option should never be necessary on usual Samba servers running only one
nmbd.
By default Samba will send UDP packets from the OS default address for the
destination, and accept replies on 0.0.0.0.
This parameter is deprecated. See bind interfaces only = Yes and interfaces for the
previous behaviour of controlling the normal listening sockets.
Default: nbt client socket address = 0.0.0.0
Example: nbt client socket address = 192.168.2.20
nbtd:wins_prepend1Bto1Cqueries (G)
Normally queries for 0x1C names (all logon servers for a domain) will return the first
address of the 0x1B names (domain master browser and PDC) as first address in the
result list. As many client only use the first address in the list by default, all
clients will use the same server (the PDC). Windows servers have an option to disable
this behavior (since Windows 2000 Service Pack 2).
Default: nbtd:wins_prepend1Bto1Cqueries = yes
nbtd:wins_wins_randomize1Clist (G)
Normally queries for 0x1C names will return the addresses in the same order as they're
stored in the database, that means first all addresses which have been directly
registered at the local wins server and then all addresses registered at other
servers. Windows servers have an option to change this behavior and randomize the
returned addresses. Set this parameter to "yes" and Samba will sort the address list
depending on the client address and the matching bits of the addresses, the first
address is randomized based on depending on the "nbtd:wins_randomize1Clist_mask"
parameter.
Default: nbtd:wins_wins_randomize1Clist = no
nbtd:wins_randomize1Clist_mask (G)
If the "nbtd:wins_randomize1Clist" parameter is set to "yes", then randomizing of the
first returned address is based on the specified netmask. If there are addresses which
are in the same subnet as the client address, the first returned address is randomly
chosen out them. Otherwise the first returned address is randomly chosen out of all
addresses.
Default: nbtd:wins_randomize1Clist_mask = 255.255.255.0
nbt port (G)
Specifies which port the server should use for NetBIOS over IP name services traffic.
Default: nbt port = 137
ncalrpc dir (G)
This directory will hold a series of named pipes to allow RPC over inter-process
communication.
This will allow Samba and other unix processes to interact over DCE/RPC without using
TCP/IP. Additionally a sub-directory 'np' has restricted permissions, and allows a
trusted communication channel between Samba processes
Default: ncalrpc dir = /run/samba/ncalrpc
Example: ncalrpc dir = /var/run/samba/ncalrpc
netbios aliases (G)
This is a list of NetBIOS names that nmbd will advertise as additional names by which
the Samba server is known. This allows one machine to appear in browse lists under
multiple names. If a machine is acting as a browse server or logon server none of
these names will be advertised as either browse server or logon servers, only the
primary name of the machine will be advertised with these capabilities.
Default: netbios aliases = # empty string (no additional names)
Example: netbios aliases = TEST TEST1 TEST2
netbios name (G)
This sets the NetBIOS name by which a Samba server is known. By default it is the same
as the first component of the host's DNS name. If a machine is a browse server or
logon server this name (or the first component of the hosts DNS name) will be the name
that these services are advertised under.
Note that the maximum length for a NetBIOS name is 15 characters.
There is a bug in Samba that breaks operation of browsing and access to shares if the
netbios name is set to the literal name PIPE. To avoid this problem, do not name your
Samba server PIPE.
Default: netbios name = # machine DNS name
Example: netbios name = MYNAME
netbios scope (G)
This sets the NetBIOS scope that Samba will operate under. This should not be set
unless every machine on your LAN also sets this value.
Default: netbios scope =
neutralize nt4 emulation (G)
This option controls whether winbindd sends the NETLOGON_NEG_NEUTRALIZE_NT4_EMULATION
flag in order to bypass the NT4 emulation of a domain controller.
Typically you should not need set this. It can be useful for upgrades from NT4 to AD
domains.
The behavior can be controlled per netbios domain by using 'neutralize nt4
emulation:NETBIOSDOMAIN = yes' as option.
Default: neutralize nt4 emulation = no
nmbd bind explicit broadcast (G)
This option causes nmbd(8) to explicitly bind to the broadcast address of the local
subnets. This is needed to make nmbd work correctly in combination with the socket
address option. You should not need to unset this option.
Default: nmbd bind explicit broadcast = yes
nsupdate command (G)
This option sets the path to the nsupdate command which is used for GSS-TSIG dynamic
DNS updates.
Default: nsupdate command = /usr/bin/nsupdate -g
nt hash store (G)
This parameter determines whether or not samba(8) will, as an AD DC, attempt to store
the NT password hash used in NTLM and NTLMv2 authentication for users in this domain.
If so configured, the Samba Active Directory Domain Controller, will, except for trust
accounts (computers, domain controllers and inter-domain trusts) the NOT store the NT
hash for new and changed accounts in the sam.ldb database.
This avoids the storage of an unsalted hash for these user-created passwords. As a
consequence the arcfour-hmac-md5 Kerberos key type is also unavailable in the KDC for
these users - thankfully modern clients will select an AES based key instead.
NOTE: As the password history in Active Directory is stored as an NT hash (and thus
unavailable), a workaround is used, relying instead on Kerberos password hash values.
This stores three passwords, the current, previous and second previous password. This
allows some checking against reuse.
However as these values are salted, changing the sAMAccountName, userAccountControl or
userPrincipalName of an account will cause the salt to change. After the rare
combination of both a rename and a password change only the current password will be
recognised for password history purposes.
The available settings are:
• always - Always store the NT hash (as machine accounts will also always
store an NT hash, a hash will be stored for all accounts).
This setting may be useful if ntlm auth is set to disabled for a trial
period
• never - Never store the NT hash for user accounts, only for machine
accounts
• auto - Store an NT hash if ntlm auth is not set to disabled.
Default: nt hash store = always
nt acl support (S)
This boolean parameter controls whether smbd(8) will attempt to map UNIX permissions
into Windows NT access control lists. The UNIX permissions considered are the
traditional UNIX owner and group permissions, as well as filesystem ACLs set on any
files or directories. This parameter was formally a global parameter in releases prior
to 2.2.2.
Default: nt acl support = yes
ntlm auth (G)
This parameter determines whether or not smbd(8) will attempt to authenticate users
using the NTLM encrypted password response for this local passdb (SAM or account
database).
If disabled, both NTLM and LanMan authentication against the local passdb is disabled.
Note that these settings apply only to local users, authentication will still be
forwarded to and NTLM authentication accepted against any domain we are joined to, and
any trusted domain, even if disabled or if NTLMv2-only is enforced here. To control
NTLM authentication for domain users, this option must be configured on each DC.
By default with ntlm auth set to ntlmv2-only only NTLMv2 logins will be permitted. All
modern clients support NTLMv2 by default, but some older clients will require special
configuration to use it.
The primary user of NTLMv1 is MSCHAPv2 for VPNs and 802.1x.
The available settings are:
• ntlmv1-permitted (alias yes) - Allow NTLMv1 and above for all clients.
This is the required setting to enable the lanman auth parameter.
• ntlmv2-only (alias no) - Do not allow NTLMv1 to be used, but permit NTLMv2.
• mschapv2-and-ntlmv2-only - Only allow NTLMv1 when the client promises that
it is providing MSCHAPv2 authentication (such as the ntlm_auth tool).
• disabled - Do not accept NTLM (or LanMan) authentication of any level, nor
permit NTLM password changes.
WARNING: Both Microsoft Windows and Samba Read Only Domain Controllers
(RODCs) convert a plain-text LDAP Simple Bind into an NTLMv2 authentication
to forward to a full DC. Setting this option to disabled will cause these
forwarded authentications to fail.
Additionally, for Samba acting as an Active Directory Domain Controller,
for user accounts, if nt hash store is set to the default setting of auto,
the NT hash will not be stored in the sam.ldb database for new users and
after a password change.
The default changed from yes to no with Samba 4.5. The default changed again to
ntlmv2-only with Samba 4.7, however the behaviour is unchanged.
Default: ntlm auth = ntlmv2-only
nt pipe support (G)
This boolean parameter controls whether smbd(8) will allow Windows NT clients to
connect to the NT SMB specific IPC$ pipes. This is a developer debugging option and
can be left alone.
Default: nt pipe support = yes
ntp signd socket directory (G)
This setting controls the location of the socket that the NTP daemon uses to
communicate with Samba for signing packets.
If a non-default path is specified here, then it is also necessary to make NTP aware
of the new path using the ntpsigndsocket directive in ntp.conf.
Default: ntp signd socket directory = /var/lib/samba/ntp_signd
nt status support (G)
This boolean parameter controls whether smbd(8) will negotiate NT specific status
support with Windows NT/2k/XP clients. This is a developer debugging option and should
be left alone. If this option is set to no then Samba offers exactly the same DOS
error codes that versions prior to Samba 2.2.3 reported.
You should not need to ever disable this parameter.
Default: nt status support = yes
ntvfs handler (S)
This specifies the NTVFS handlers for this share.
• unixuid: Sets up user credentials based on POSIX gid/uid.
• cifs: Proxies a remote CIFS FS. Mainly useful for testing.
• nbench: Filter module that saves data useful to the nbench benchmark suite.
• ipc: Allows using SMB for inter process communication. Only used for the
IPC$ share.
• posix: Maps POSIX FS semantics to NT semantics
• print: Allows printing over SMB. This is LANMAN-style printing, not the be
confused with the spoolss DCE/RPC interface used by later versions of
Windows.
Note that this option is only used when the NTVFS file server is in use. It is not
used with the (default) s3fs file server.
Default: ntvfs handler = unixuid, default
null passwords (G)
Allow or disallow client access to accounts that have null passwords.
See also smbpasswd(5).
Default: null passwords = no
obey pam restrictions (G)
When Samba 3.0 is configured to enable PAM support (i.e. --with-pam), this parameter
will control whether or not Samba should obey PAM's account and session management
directives. The default behavior is to use PAM for clear text authentication only and
to ignore any account or session management. Note that Samba always ignores PAM for
authentication in the case of encrypt passwords = yes. The reason is that PAM modules
cannot support the challenge/response authentication mechanism needed in the presence
of SMB password encryption.
Default: obey pam restrictions = no
old password allowed period (G)
Number of minutes to permit an NTLM login after a password change or reset using the
old password. This allows the user to re-cache the new password on multiple clients
without disrupting a network reconnection in the meantime.
This parameter only applies when server role is set to Active Directory Domain
Controller.
Default: old password allowed period = 60
oplock break wait time (G)
This is a tuning parameter added due to bugs in both Windows 9x and WinNT. If Samba
responds to a client too quickly when that client issues an SMB that can cause an
oplock break request, then the network client can fail and not respond to the break
request. This tuning parameter (which is set in milliseconds) is the amount of time
Samba will wait before sending an oplock break request to such (broken) clients.
Warning
DO NOT CHANGE THIS PARAMETER UNLESS YOU HAVE READ AND UNDERSTOOD THE SAMBA OPLOCK
CODE.
Default: oplock break wait time = 0
oplocks (S)
This boolean option tells smbd whether to issue oplocks (opportunistic locks) to file
open requests on this share. The oplock code can dramatically (approx. 30% or more)
improve the speed of access to files on Samba servers. It allows the clients to
aggressively cache files locally and you may want to disable this option for
unreliable network environments (it is turned on by default in Windows NT Servers).
Oplocks may be selectively turned off on certain files with a share. See the veto
oplock files parameter. On some systems oplocks are recognized by the underlying
operating system. This allows data synchronization between all access to oplocked
files, whether it be via Samba or NFS or a local UNIX process. See the kernel oplocks
parameter for details.
Default: oplocks = yes
os2 driver map (G)
The parameter is used to define the absolute path to a file containing a mapping of
Windows NT printer driver names to OS/2 printer driver names. The format is:
<nt driver name> = <os2 driver name>.<device name>
For example, a valid entry using the HP LaserJet 5 printer driver would appear as HP
LaserJet 5L = LASERJET.HP LaserJet 5L.
The need for the file is due to the printer driver namespace problem described in the
chapter on Classical Printing in the Samba3-HOWTO book. For more details on OS/2
clients, please refer to chapter on other clients in the Samba3-HOWTO book.
Default: os2 driver map =
os level (G)
This integer value controls what level Samba advertises itself as for browse
elections. The value of this parameter determines whether nmbd(8) has a chance of
becoming a local master browser for the workgroup in the local broadcast area.
Note: By default, Samba will win a local master browsing election over all Microsoft
operating systems except a Windows NT 4.0/2000 Domain Controller. This means that a
misconfigured Samba host can effectively isolate a subnet for browsing purposes. This
parameter is largely auto-configured in the Samba-3 release series and it is seldom
necessary to manually override the default setting. Please refer to the chapter on
Network Browsing in the Samba-3 HOWTO document for further information regarding the
use of this parameter. Note: The maximum value for this parameter is 255. If you use
higher values, counting will start at 0!
Default: os level = 20
Example: os level = 65
pam password change (G)
With the addition of better PAM support in Samba 2.2, this parameter, it is possible
to use PAM's password change control flag for Samba. If enabled, then PAM will be used
for password changes when requested by an SMB client instead of the program listed in
passwd program. It should be possible to enable this without changing your passwd chat
parameter for most setups.
Default: pam password change = no
panic action (G)
This is a Samba developer option that allows a system command to be called when either
smbd(8) or nmbd(8) crashes. This is usually used to draw attention to the fact that a
problem occurred.
Default: panic action =
Example: panic action = /bin/sleep 90000
passdb backend (G)
This option allows the administrator to chose which backend will be used for storing
user and possibly group information. This allows you to swap between different storage
mechanisms without recompile.
The parameter value is divided into two parts, the backend's name, and a 'location'
string that has meaning only to that particular backed. These are separated by a :
character.
Available backends can include:
• smbpasswd - The old plaintext passdb backend. Some Samba features will not
work if this passdb backend is used. Takes a path to the smbpasswd file as
an optional argument.
• tdbsam - The TDB based password storage backend. Takes a path to the TDB as
an optional argument (defaults to passdb.tdb in the private dir directory.
• ldapsam - The LDAP based passdb backend. Takes an LDAP URL as an optional
argument (defaults to ldap://localhost)
LDAP connections should be secured where possible. This may be done using
either Start-TLS (see ldap ssl) or by specifying ldaps:// in the URL
argument.
Multiple servers may also be specified in double-quotes. Whether multiple
servers are supported or not and the exact syntax depends on the LDAP
library you use.
Examples of use are:
passdb backend = tdbsam:/etc/samba/private/passdb.tdb
or multi server LDAP URL with OpenLDAP library:
passdb backend = ldapsam:"ldap://ldap-1.example.com ldap://ldap-2.example.com"
or multi server LDAP URL with Netscape based LDAP library:
passdb backend = ldapsam:"ldap://ldap-1.example.com ldap-2.example.com"
Default: passdb backend = tdbsam
passdb expand explicit (G)
This parameter controls whether Samba substitutes %-macros in the passdb fields if
they are explicitly set. We used to expand macros here, but this turned out to be a
bug because the Windows client can expand a variable %G_osver% in which %G would have
been substituted by the user's primary group.
Default: passdb expand explicit = no
passwd chat (G)
This string controls the "chat" conversation that takes places between smbd(8) and the
local password changing program to change the user's password. The string describes a
sequence of response-receive pairs that smbd(8) uses to determine what to send to the
passwd program and what to expect back. If the expected output is not received then
the password is not changed.
This chat sequence is often quite site specific, depending on what local methods are
used for password control.
Note that this parameter only is used if the unix password sync parameter is set to
yes. This sequence is then called AS ROOT when the SMB password in the smbpasswd file
is being changed, without access to the old password cleartext. This means that root
must be able to reset the user's password without knowing the text of the previous
password.
The string can contain the macro %n which is substituted for the new password. The old
password (%o) is only available when encrypt passwords has been disabled. The chat
sequence can also contain the standard macros \n, \r, \t and \s to give line-feed,
carriage-return, tab and space. The chat sequence string can also contain a '*' which
matches any sequence of characters. Double quotes can be used to collect strings with
spaces in them into a single string.
If the send string in any part of the chat sequence is a full stop ".", then no string
is sent. Similarly, if the expect string is a full stop then no string is expected.
If the pam password change parameter is set to yes, the chat pairs may be matched in
any order, and success is determined by the PAM result, not any particular output. The
\n macro is ignored for PAM conversions.
Default: passwd chat = *new*password* %n\n *new*password* %n\n *changed*
Example: passwd chat = "*Enter NEW password*" %n\n "*Reenter NEW password*" %n\n
"*Password changed*"
passwd chat debug (G)
This boolean specifies if the passwd chat script parameter is run in debug mode. In
this mode the strings passed to and received from the passwd chat are printed in the
smbd(8) log with a debug level of 100. This is a dangerous option as it will allow
plaintext passwords to be seen in the smbd log. It is available to help Samba admins
debug their passwd chat scripts when calling the passwd program and should be turned
off after this has been done. This option has no effect if the pam password change
parameter is set. This parameter is off by default.
Default: passwd chat debug = no
passwd chat timeout (G)
This integer specifies the number of seconds smbd will wait for an initial answer from
a passwd chat script being run. Once the initial answer is received the subsequent
answers must be received in one tenth of this time. The default it two seconds.
Default: passwd chat timeout = 2
passwd program (G)
The name of a program that can be used to set UNIX user passwords. Any occurrences of
%u will be replaced with the user name. The user name is checked for existence before
calling the password changing program.
Also note that many passwd programs insist in reasonable passwords, such as a minimum
length, or the inclusion of mixed case chars and digits. This can pose a problem as
some clients (such as Windows for Workgroups) uppercase the password before sending
it.
Note that if the unix password sync parameter is set to yes then this program is
called AS ROOT before the SMB password in the smbpasswd file is changed. If this UNIX
password change fails, then smbd will fail to change the SMB password also (this is by
design).
If the unix password sync parameter is set this parameter MUST USE ABSOLUTE PATHS for
ALL programs called, and must be examined for security implications. Note that by
default unix password sync is set to no.
Default: passwd program =
Example: passwd program = /bin/passwd %u
password hash gpg key ids (G)
If samba is running as an active directory domain controller, it is possible to store
the cleartext password of accounts in a PGP/OpenGPG encrypted form.
You can specify one or more recipients by key id or user id. Note that 32bit key ids
are not allowed, specify at least 64bit.
The value is stored as 'Primary:SambaGPG' in the supplementalCredentials attribute.
As password changes can occur on any domain controller, you should configure this on
each of them. Note that this feature is currently available only on Samba domain
controllers.
This option is only available if samba was compiled with gpgme support.
You may need to export the GNUPGHOME environment variable before starting samba. It
is strongly recommended to only store the public key in this location. The private key
is not used for encryption and should be only stored where decryption is required.
Being able to restore the cleartext password helps, when they need to be imported into
other authentication systems later (see samba-tool user getpassword) or you want to
keep the passwords in sync with another system, e.g. an OpenLDAP server (see
samba-tool user syncpasswords).
While this option needs to be configured on all domain controllers, the samba-tool
user syncpasswords command should run on a single domain controller only (typically
the PDC-emulator).
Default: password hash gpg key ids =
Example: password hash gpg key ids = 4952E40301FAB41A
Example: password hash gpg key ids = selftest@samba.example.com
Example: password hash gpg key ids = selftest@samba.example.com, 4952E40301FAB41A
password hash userPassword schemes (G)
This parameter determines whether or not samba(8) acting as an Active Directory Domain
Controller will attempt to store additional passwords hash types for the user
The values are stored as 'Primary:userPassword' in the supplementalCredentials
attribute. The value of this option is a hash type.
The currently supported hash types are:
• CryptSHA256
• CryptSHA512
Multiple instances of a hash type may be computed and stored. The password hashes are
calculated using the crypt(3) call. The number of rounds used to compute the hash can
be specified by adding ':rounds=xxxx' to the hash type, i.e. CryptSHA512:rounds=4500
would calculate an SHA512 hash using 4500 rounds. If not specified the Operating
System defaults for crypt(3) are used.
As password changes can occur on any domain controller, you should configure this on
each of them. Note that this feature is currently available only on Samba domain
controllers.
Currently the NT Hash of the password is recorded when these hashes are calculated and
stored. When retrieving the hashes the current value of the NT Hash is checked against
the stored NT Hash. This detects password changes that have not updated the password
hashes. In this case samba-tool user will ignore the stored hash values.
Being able to obtain the hashed password helps, when they need to be imported into
other authentication systems later (see samba-tool user getpassword) or you want to
keep the passwords in sync with another system, e.g. an OpenLDAP server (see
samba-tool user syncpasswords).
Related command: unix password sync
Default: password hash userPassword schemes =
Example: password hash userPassword schemes = CryptSHA256
Example: password hash userPassword schemes = CryptSHA256 CryptSHA512
Example: password hash userPassword schemes = CryptSHA256:rounds=5000
CryptSHA512:rounds=7000
password server (G)
By specifying the name of a domain controller with this option, and using security =
[ads|domain] it is possible to get Samba to do all its username/password validation
using a specific remote server.
Ideally, this option should not be used, as the default '*' indicates to Samba to
determine the best DC to contact dynamically, just as all other hosts in an AD domain
do. This allows the domain to be maintained (addition and removal of domain
controllers) without modification to the smb.conf file. The cryptographic protection
on the authenticated RPC calls used to verify passwords ensures that this default is
safe.
It is strongly recommended that you use the default of '*', however if in your
particular environment you have reason to specify a particular DC list, then the list
of machines in this option must be a list of names or IP addresses of Domain
controllers for the Domain. If you use the default of '*', or list several hosts in
the password server option then smbd will try each in turn till it finds one that
responds. This is useful in case your primary server goes down.
If the list of servers contains both names/IP's and the '*' character, the list is
treated as a list of preferred domain controllers, but an auto lookup of all remaining
DC's will be added to the list as well. Samba will not attempt to optimize this list
by locating the closest DC.
If parameter is a name, it is looked up using the parameter name resolve order and so
may resolved by any method and order described in that parameter.
Default: password server = *
Example: password server = NT-PDC, NT-BDC1, NT-BDC2, *
Example: password server = windc.mydomain.com:389 192.168.1.101 *
directory
This parameter is a synonym for path.
path (S)
This parameter specifies a directory to which the user of the service is to be given
access. In the case of printable services, this is where print data will spool prior
to being submitted to the host for printing.
For a printable service offering guest access, the service should be readonly and the
path should be world-writeable and have the sticky bit set. This is not mandatory of
course, but you probably won't get the results you expect if you do otherwise.
Any occurrences of %u in the path will be replaced with the UNIX username that the
client is using on this connection. Any occurrences of %m will be replaced by the
NetBIOS name of the machine they are connecting from. These replacements are very
useful for setting up pseudo home directories for users.
Note that this path will be based on root dir if one was specified.
Default: path =
Example: path = /home/fred
perfcount module (G)
This parameter specifies the perfcount backend to be used when monitoring SMB
operations. Only one perfcount module may be used, and it must implement all of the
apis contained in the smb_perfcount_handler structure defined in smb.h.
No default
pid directory (G)
This option specifies the directory where pid files will be placed.
Default: pid directory = /run/samba
Example: pid directory = /var/run/
posix locking (S)
The smbd(8) daemon maintains an database of file locks obtained by SMB clients. The
default behavior is to map this internal database to POSIX locks. This means that file
locks obtained by SMB clients are consistent with those seen by POSIX compliant
applications accessing the files via a non-SMB method (e.g. NFS or local file access).
It is very unlikely that you need to set this parameter to "no", unless you are
sharing from an NFS mount, which is not a good idea in the first place.
Default: posix locking = yes
postexec (S)
This option specifies a command to be run whenever the service is disconnected. It
takes the usual substitutions. The command may be run as the root on some systems.
An interesting example may be to unmount server resources:
postexec = /etc/umount /cdrom
Default: postexec =
Example: postexec = echo \"%u disconnected from %S from %m (%I)\" >> /tmp/log
exec
This parameter is a synonym for preexec.
preexec (S)
This option specifies a command to be run whenever the service is connected to. It
takes the usual substitutions.
An interesting example is to send the users a welcome message every time they log in.
Maybe a message of the day? Here is an example:
preexec = csh -c 'echo \"Welcome to %S!\" | /usr/local/samba/bin/smbclient -M %m -I
%I' &
Of course, this could get annoying after a while :-)
See also preexec close and postexec.
Default: preexec =
Example: preexec = echo \"%u connected to %S from %m (%I)\" >> /tmp/log
preexec close (S)
This boolean option controls whether a non-zero return code from preexec should close
the service being connected to.
Default: preexec close = no
prefered master
This parameter is a synonym for preferred master.
preferred master (G)
This boolean parameter controls if nmbd(8) is a preferred master browser for its
workgroup.
If this is set to yes, on startup, nmbd will force an election, and it will have a
slight advantage in winning the election. It is recommended that this parameter is
used in conjunction with domain master = yes, so that nmbd can guarantee becoming a
domain master.
Use this option with caution, because if there are several hosts (whether Samba
servers, Windows 95 or NT) that are preferred master browsers on the same subnet, they
will each periodically and continuously attempt to become the local master browser.
This will result in unnecessary broadcast traffic and reduced browsing capabilities.
Default: preferred master = auto
prefork backoff increment (G)
This option specifies the number of seconds added to the delay before a prefork master
or worker process is restarted. The restart is initially zero, the prefork backoff
increment is added to the delay on each restart up to the value specified by "prefork
maximum backoff".
Additionally set the backoff for an individual service by using "prefork backoff
increment: service name" i.e. "prefork backoff increment:ldap = 2" to set the backoff
increment to 2.
If the backoff increment is 2 and the maximum backoff is 5. There will be a zero
second delay for the first restart. A two second delay for the second restart. A four
second delay for the third and any subsequent restarts
Default: prefork backoff increment = 10
prefork children (G)
This option controls the number of worker processes that are started for each service
when prefork process model is enabled (see samba(8) -M) The prefork children are only
started for those services that support prefork (currently ldap, kdc and netlogon).
For processes that don't support preforking all requests are handled by a single
process for that service.
This should be set to a small multiple of the number of CPU's available on the server
Additionally the number of prefork children can be specified for an individual service
by using "prefork children: service name" i.e. "prefork children:ldap = 8" to set the
number of ldap worker processes.
Default: prefork children = 4
prefork maximum backoff (G)
This option controls the maximum delay before a failed pre-fork process is restarted.
Default: prefork maximum backoff = 120
preload modules (G)
This is a list of paths to modules that should be loaded into smbd before a client
connects. This improves the speed of smbd when reacting to new connections somewhat.
Default: preload modules =
Example: preload modules = /usr/lib/samba/passdb/mysql.so
preserve case (S)
This controls if new filenames are created with the case that the client passes, or if
they are forced to be the default case.
See the section on NAME MANGLING for a fuller discussion.
Default: preserve case = yes
print ok
This parameter is a synonym for printable.
printable (S)
If this parameter is yes, then clients may open, write to and submit spool files on
the directory specified for the service.
Note that a printable service will ALWAYS allow writing to the service path (user
privileges permitting) via the spooling of print data. The read only parameter
controls only non-printing access to the resource.
Default: printable = no
printcap cache time (G)
This option specifies the number of seconds before the printing subsystem is again
asked for the known printers.
Setting this parameter to 0 disables any rescanning for new or removed printers after
the initial startup.
Default: printcap cache time = 750
Example: printcap cache time = 600
printcap
This parameter is a synonym for printcap name.
printcap name (G)
This parameter may be used to override the compiled-in default printcap name used by
the server (usually /etc/printcap). See the discussion of the [printers] section above
for reasons why you might want to do this.
To use the CUPS printing interface set printcap name = cups. This should be
supplemented by an additional setting printing = cups in the [global] section.
printcap name = cups will use the "dummy" printcap created by CUPS, as specified in
your CUPS configuration file.
On System V systems that use lpstat to list available printers you can use printcap
name = lpstat to automatically obtain lists of available printers. This is the default
for systems that define SYSV at configure time in Samba (this includes most System V
based systems). If
printcap name is set to lpstat on these systems then Samba will launch lpstat -v and
attempt to parse the output to obtain a printer list.
A minimal printcap file would look something like this:
print1|My Printer 1
print2|My Printer 2
print3|My Printer 3
print4|My Printer 4
print5|My Printer 5
where the '|' separates aliases of a printer. The fact that the second alias has a
space in it gives a hint to Samba that it's a comment.
Note
Under AIX the default printcap name is /etc/qconfig. Samba will assume the file is
in AIX qconfig format if the string qconfig appears in the printcap filename.
Default: printcap name = /etc/printcap
Example: printcap name = /etc/myprintcap
print command (S)
After a print job has finished spooling to a service, this command will be used via a
system() call to process the spool file. Typically the command specified will submit
the spool file to the host's printing subsystem, but there is no requirement that this
be the case. The server will not remove the spool file, so whatever command you
specify should remove the spool file when it has been processed, otherwise you will
need to manually remove old spool files.
The print command is simply a text string. It will be used verbatim after macro
substitutions have been made:
%s, %f - the path to the spool file name
%p - the appropriate printer name
%J - the job name as transmitted by the client.
%c - The number of printed pages of the spooled job (if known).
%z - the size of the spooled print job (in bytes)
The print command MUST contain at least one occurrence of %s or %f - the %p is
optional. At the time a job is submitted, if no printer name is supplied the %p will
be silently removed from the printer command.
If specified in the [global] section, the print command given will be used for any
printable service that does not have its own print command specified.
If there is neither a specified print command for a printable service nor a global
print command, spool files will be created but not processed and (most importantly)
not removed.
Note that printing may fail on some UNIXes from the nobody account. If this happens
then create an alternative guest account that can print and set the guest account in
the [global] section.
You can form quite complex print commands by realizing that they are just passed to a
shell. For example the following will log a print job, print the file, then remove it.
Note that ';' is the usual separator for command in shell scripts.
print command = echo Printing %s >> /tmp/print.log; lpr -P %p %s; rm %s
You may have to vary this command considerably depending on how you normally print
files on your system. The default for the parameter varies depending on the setting of
the printing parameter.
Default: For printing = BSD, AIX, QNX, LPRNG or PLP :
print command = lpr -r -P%p %s
For printing = SYSV or HPUX :
print command = lp -c -d%p %s; rm %s
For printing = SOFTQ :
print command = lp -d%p -s %s; rm %s
For printing = CUPS : If SAMBA is compiled against libcups, then printcap = cups uses
the CUPS API to submit jobs, etc. Otherwise it maps to the System V commands with the
-oraw option for printing, i.e. it uses lp -c -d%p -oraw; rm %s. With printing = cups,
and if SAMBA is compiled against libcups, any manually set print command will be
ignored.
No default
Example: print command = /usr/local/samba/bin/myprintscript %p %s
printer
This parameter is a synonym for printer name.
printer name (S)
This parameter specifies the name of the printer to which print jobs spooled through a
printable service will be sent.
If specified in the [global] section, the printer name given will be used for any
printable service that does not have its own printer name specified.
The default value of the printer name may be lp on many systems.
Default: printer name =
Example: printer name = laserwriter
printing (S)
This parameters controls how printer status information is interpreted on your system.
It also affects the default values for the print command, lpq command, lppause command
, lpresume command, and lprm command if specified in the [global] section.
Currently nine printing styles are supported. They are BSD, AIX, LPRNG, PLP, SYSV,
HPUX, QNX, SOFTQ, CUPS and IPRINT.
Be aware that CUPS and IPRINT are only available if the CUPS development library was
available at the time Samba was compiled or packaged.
To see what the defaults are for the other print commands when using the various
options use the testparm(1) program.
This option can be set on a per printer basis. Please be aware however, that you must
place any of the various printing commands (e.g. print command, lpq command, etc...)
after defining the value for the printing option since it will reset the printing
commands to default values.
See also the discussion in the [printers] section.
See testparm -v. for the default value on your system
Default: printing = # Depends on the operating system
printjob username (S)
This parameter specifies which user information will be passed to the printing system.
Usually, the username is sent, but in some cases, e.g. the domain prefix is useful,
too.
Default: printjob username = %U
Example: printjob username = %D\%U
print notify backchannel (S)
Windows print clients can update print queue status by expecting the server to open a
backchannel SMB connection to them. Due to client firewall settings this can cause
considerable timeouts and will often fail, as there is no guarantee the client is even
running an SMB server. By default, the Samba print server will not try to connect back
to clients, and will treat corresponding requests as if the connection back to the
client failed.
Default: print notify backchannel = no
private directory
This parameter is a synonym for private dir.
private dir (G)
This parameters defines the directory smbd will use for storing such files as
smbpasswd and secrets.tdb.
Default: private dir = /var/lib/samba/private
queuepause command (S)
This parameter specifies the command to be executed on the server host in order to
pause the printer queue.
This command should be a program or script which takes a printer name as its only
parameter and stops the printer queue, such that no longer jobs are submitted to the
printer.
This command is not supported by Windows for Workgroups, but can be issued from the
Printers window under Windows 95 and NT.
If a %p is given then the printer name is put in its place. Otherwise it is placed at
the end of the command.
Note that it is good practice to include the absolute path in the command as the PATH
may not be available to the server.
Default: queuepause command = # determined by printing parameter
Example: queuepause command = disable %p
queueresume command (S)
This parameter specifies the command to be executed on the server host in order to
resume the printer queue. It is the command to undo the behavior that is caused by the
previous parameter (queuepause command).
This command should be a program or script which takes a printer name as its only
parameter and resumes the printer queue, such that queued jobs are resubmitted to the
printer.
This command is not supported by Windows for Workgroups, but can be issued from the
Printers window under Windows 95 and NT.
If a %p is given then the printer name is put in its place. Otherwise it is placed at
the end of the command.
Note that it is good practice to include the absolute path in the command as the PATH
may not be available to the server.
Default: queueresume command = # determined by printing parameter
Example: queueresume command = enable %p
raw NTLMv2 auth (G)
This parameter has been deprecated since Samba 4.13 and support for NTLMv2
authentication without NTLMSSP will be removed in a future Samba release.
That is, in the future, the current default of raw NTLMv2 auth = no will be the
enforced behaviour.
This parameter determines whether or not smbd(8) will allow SMB1 clients without
extended security (without SPNEGO) to use NTLMv2 authentication.
If this option, lanman auth and ntlm auth are all disabled, then only clients with
SPNEGO support will be permitted. That means NTLMv2 is only supported within NTLMSSP.
Default: raw NTLMv2 auth = no
read list (S)
This is a list of users that are given read-only access to a service. If the
connecting user is in this list then they will not be given write access, no matter
what the read only option is set to. The list can include group names using the syntax
described in the invalid users parameter.
Default: read list =
Example: read list = mary, @students
read only (S)
An inverted synonym is writeable.
If this parameter is yes, then users of a service may not create or modify files in
the service's directory.
Note that a printable service (printable = yes) will ALWAYS allow writing to the
directory (user privileges permitting), but only via spooling operations.
Default: read only = yes
read raw (G)
This is ignored if async smb echo handler is set, because this feature is incompatible
with raw read SMB requests
If enabled, raw reads allow reads of 65535 bytes in one packet. This typically
provides a major performance benefit for some very, very old clients.
However, some clients either negotiate the allowable block size incorrectly or are
incapable of supporting larger block sizes, and for these clients you may need to
disable raw reads.
In general this parameter should be viewed as a system tuning tool and left severely
alone.
Default: read raw = yes
realm (G)
This option specifies the kerberos realm to use. The realm is used as the ADS
equivalent of the NT4 domain. It is usually set to the DNS name of the kerberos
server.
Default: realm =
Example: realm = mysambabox.mycompany.com
registry shares (G)
This turns on or off support for share definitions read from registry. Shares defined
in smb.conf take precedence over shares with the same name defined in registry. See
the section on registry-based configuration for details.
Note that this parameter defaults to no, but it is set to yes when config backend is
set to registry.
Default: registry shares = no
Example: registry shares = yes
reject md5 clients (G)
This option is deprecated and will be removed in a future release, as it is a security
problem if not set to "yes" (which will be the hardcoded behavior in the future).
This option controls whether the netlogon server (currently only in 'active directory
domain controller' mode), will reject clients which does not support
NETLOGON_NEG_SUPPORTS_AES.
Support for NETLOGON_NEG_SUPPORTS_AES was added in Windows starting with Server 2008R2
and Windows 7, it's available in Samba starting with 4.0, however third party domain
members like NetApp ONTAP still uses RC4 (HMAC-MD5), see
https://www.samba.org/samba/security/CVE-2022-38023.html for more details.
The default changed from 'no' to 'yes', with the patches for CVE-2022-38023 see
https://bugzilla.samba.org/show_bug.cgi?id=15240.
Avoid using this option! Use an explicit per machine account 'server reject md5
schannel:COMPUTERACCOUNT' instead! Which is available with the patches for
CVE-2022-38023 see https://bugzilla.samba.org/show_bug.cgi?id=15240.
Samba will log an error in the log files at log level 0 if legacy a client is rejected
or allowed without an explicit, 'server reject md5 schannel:COMPUTERACCOUNT = no'
option for the client. The message will indicate the explicit 'server reject md5
schannel:COMPUTERACCOUNT = no' line to be added, if the legacy client software
requires it. (The log level can be adjusted with 'CVE_2022_38023:error_debug_level =
1' in order to complain only at a higher log level).
This allows admins to use "no" only for a short grace period, in order to collect the
explicit 'server reject md5 schannel:COMPUTERACCOUNT = no' options.
When set to 'yes' this option overrides the 'allow nt4 crypto:COMPUTERACCOUNT' and
'allow nt4 crypto' options and implies 'allow nt4 crypto:COMPUTERACCOUNT = no'.
Default: reject md5 clients = yes
server reject md5 schannel:COMPUTERACCOUNT (G)
If you still have legacy domain members or trusted domains, which required "reject md5
clients = no" before, it is possible to specify an explicit exception per computer
account by setting 'server reject md5 schannel:COMPUTERACCOUNT = no'. Note that
COMPUTERACCOUNT has to be the sAMAccountName value of the computer account (including
the trailing '$' sign).
Samba will log a complaint in the log files at log level 0 about the security problem
if the option is set to "no", but the related computer does not require it. (The log
level can be adjusted with 'CVE_2022_38023:warn_about_unused_debug_level = 1' in order
to complain only at a higher log level).
Samba will log a warning in the log files at log level 5 if a setting is still needed
for the specified computer account.
See CVE-2022-38023, https://bugzilla.samba.org/show_bug.cgi?id=15240.
This option overrides the reject md5 clients option.
When set to 'yes' this option overrides the 'allow nt4 crypto:COMPUTERACCOUNT' and
'allow nt4 crypto' options and implies 'allow nt4 crypto:COMPUTERACCOUNT = no'.
server reject md5 schannel:LEGACYCOMPUTER1$ = no
server reject md5 schannel:NASBOX$ = no
server reject md5 schannel:LEGACYCOMPUTER2$ = no
No default
reject md5 servers (G)
This option controls whether winbindd requires support for aes support for the
netlogon secure channel.
The following flags will be required NETLOGON_NEG_ARCFOUR, NETLOGON_NEG_SUPPORTS_AES,
NETLOGON_NEG_PASSWORD_SET2 and NETLOGON_NEG_AUTHENTICATED_RPC.
You can set this to yes if all domain controllers support aes. This will prevent
downgrade attacks.
The behavior can be controlled per netbios domain by using 'reject md5
servers:NETBIOSDOMAIN = no' as option.
The default changed from 'no' to 'yes, with the patches for CVE-2022-38023, see
https://bugzilla.samba.org/show_bug.cgi?id=15240
This option overrides the require strong key option.
Default: reject md5 servers = yes
remote announce (G)
This option allows you to setup nmbd(8) to periodically announce itself to arbitrary
IP addresses with an arbitrary workgroup name.
This is useful if you want your Samba server to appear in a remote workgroup for which
the normal browse propagation rules don't work. The remote workgroup can be anywhere
that you can send IP packets to.
For example:
remote announce = 192.168.2.255/SERVERS 192.168.4.255/STAFF
the above line would cause nmbd to announce itself to the two given IP addresses using
the given workgroup names. If you leave out the workgroup name, then the one given in
the workgroup parameter is used instead.
The IP addresses you choose would normally be the broadcast addresses of the remote
networks, but can also be the IP addresses of known browse masters if your network
config is that stable.
See the chapter on Network Browsing in the Samba-HOWTO book.
Default: remote announce =
remote browse sync (G)
This option allows you to setup nmbd(8) to periodically request synchronization of
browse lists with the master browser of a Samba server that is on a remote segment.
This option will allow you to gain browse lists for multiple workgroups across routed
networks. This is done in a manner that does not work with any non-Samba servers.
This is useful if you want your Samba server and all local clients to appear in a
remote workgroup for which the normal browse propagation rules don't work. The remote
workgroup can be anywhere that you can send IP packets to.
For example:
remote browse sync = 192.168.2.255 192.168.4.255
the above line would cause nmbd to request the master browser on the specified subnets
or addresses to synchronize their browse lists with the local server.
The IP addresses you choose would normally be the broadcast addresses of the remote
networks, but can also be the IP addresses of known browse masters if your network
config is that stable. If a machine IP address is given Samba makes NO attempt to
validate that the remote machine is available, is listening, nor that it is in fact
the browse master on its segment.
The remote browse sync may be used on networks where there is no WINS server, and may
be used on disjoint networks where each network has its own WINS server.
Default: remote browse sync =
rename user script (G)
This is the full pathname to a script that will be run as root by smbd(8) under
special circumstances described below.
When a user with admin authority or SeAddUserPrivilege rights renames a user (e.g.:
from the NT4 User Manager for Domains), this script will be run to rename the POSIX
user. Two variables, %uold and %unew, will be substituted with the old and new
usernames, respectively. The script should return 0 upon successful completion, and
nonzero otherwise.
Note
The script has all responsibility to rename all the necessary data that is
accessible in this posix method. This can mean different requirements for
different backends. The tdbsam and smbpasswd backends will take care of the
contents of their respective files, so the script is responsible only for changing
the POSIX username, and other data that may required for your circumstances, such
as home directory. Please also consider whether or not you need to rename the
actual home directories themselves. The ldapsam backend will not make any changes,
because of the potential issues with renaming the LDAP naming attribute. In this
case the script is responsible for changing the attribute that samba uses (uid)
for locating users, as well as any data that needs to change for other
applications using the same directory.
Default: rename user script =
require strong key (G)
This option controls whether winbindd requires support for md5 strong key support for
the netlogon secure channel.
The following flags will be required NETLOGON_NEG_STRONG_KEYS, NETLOGON_NEG_ARCFOUR
and NETLOGON_NEG_AUTHENTICATED_RPC.
You can set this to no if some domain controllers only support des. This might allows
weak crypto to be negotiated, may via downgrade attacks.
The behavior can be controlled per netbios domain by using 'require strong
key:NETBIOSDOMAIN = no' as option.
Note for active directory domain this option is hardcoded to 'yes'
This option is over-ridden by the reject md5 servers option.
This option overrides the client schannel option.
Default: require strong key = yes
reset on zero vc (G)
This boolean option controls whether an incoming SMB1 session setup should kill other
connections coming from the same IP. This matches the default Windows 2003 behaviour.
Setting this parameter to yes becomes necessary when you have a flaky network and
windows decides to reconnect while the old connection still has files with share modes
open. These files become inaccessible over the new connection. The client sends a zero
VC on the new connection, and Windows 2003 kills all other connections coming from the
same IP. This way the locked files are accessible again. Please be aware that enabling
this option will kill connections behind a masquerading router, and will not trigger
for clients that only use SMB2 or SMB3.
Default: reset on zero vc = no
restrict anonymous (G)
The setting of this parameter determines whether SAMR and LSA DCERPC services can be
accessed anonymously. This corresponds to the following Windows Server registry
options:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\RestrictAnonymous
The option also affects the browse option which is required by legacy clients which
rely on Netbios browsing. While modern Windows version should be fine with restricting
the access there could still be applications relying on anonymous access.
Setting restrict anonymous = 1 will disable anonymous SAMR access.
Setting restrict anonymous = 2 will, in addition to restricting SAMR access, disallow
anonymous connections to the IPC$ share in general. Setting guest ok = yes on any
share will remove the security advantage.
Default: restrict anonymous = 0
root
This parameter is a synonym for root directory.
root dir
This parameter is a synonym for root directory.
root directory (G)
The server will chroot() (i.e. Change its root directory) to this directory on
startup. This is not strictly necessary for secure operation. Even without it the
server will deny access to files not in one of the service entries. It may also check
for, and deny access to, soft links to other parts of the filesystem, or attempts to
use ".." in file names to access other directories (depending on the setting of the
wide links parameter).
Adding a root directory entry other than "/" adds an extra level of security, but at a
price. It absolutely ensures that no access is given to files not in the sub-tree
specified in the root directory option, including some files needed for complete
operation of the server. To maintain full operability of the server you will need to
mirror some system files into the root directory tree. In particular you will need to
mirror /etc/passwd (or a subset of it), and any binaries or configuration files needed
for printing (if required). The set of files that must be mirrored is operating system
dependent.
Default: root directory =
Example: root directory = /homes/smb
root postexec (S)
This is the same as the postexec parameter except that the command is run as root.
This is useful for unmounting filesystems (such as CDROMs) after a connection is
closed.
Default: root postexec =
root preexec (S)
This is the same as the preexec parameter except that the command is run as root. This
is useful for mounting filesystems (such as CDROMs) when a connection is opened.
Default: root preexec =
root preexec close (S)
This is the same as the preexec close parameter except that the command is run as
root.
Default: root preexec close = no
rpc big endian (G)
Setting this option will force the RPC client and server to transfer data in big
endian.
If it is disabled, data will be transferred in little endian.
The behaviour is independent of the endianness of the host machine.
Default: rpc big endian = no
rpc server dynamic port range (G)
This parameter tells the RPC server which port range it is allowed to use to create a
listening socket for LSA, SAM, Netlogon and others without wellknown tcp ports. The
first value is the lowest number of the port range and the second the highest.
This applies to RPC servers in all server roles.
Default: rpc server dynamic port range = 49152-65535
rpc server port (G)
Specifies which port the server should listen on for DCE/RPC over TCP/IP traffic.
This controls the default port for all protocols, except for NETLOGON.
If unset, the first available port from rpc server dynamic port range is used, e.g.
49152.
The NETLOGON server will use the next available port, e.g. 49153. To change this port
use (eg) rpc server port:netlogon = 4000.
Furthermore, all RPC servers can have the port they use specified independenty, with
(for example) rpc server port:drsuapi = 5000.
This option applies currently only when samba(8) runs as an active directory domain
controller.
The default value 0 causes Samba to select the first available port from rpc server
dynamic port range.
Default: rpc server port = 0
rpc start on demand helpers (G)
This global parameter determines if samba-dcerpcd should be started on demand to
service named pipe (np) DCE-RPC requests from smbd or winbindd. This is the normal
case where no startup scripts have been modified to start samba-dcerpcd as a daemon.
If samba-dcerpcd is started as a daemon or via a system service manager such as
systemd, this parameter MUST be set to "no", otherwise samba-dcerpcd will fail to
start.
Default: rpc start on demand helpers = yes
samba kcc command (G)
This option specifies the path to the Samba KCC command. This script is used for
replication topology replication.
It should not be necessary to modify this option except for testing purposes or if the
samba_kcc was installed in a non-default location.
Default: samba kcc command = /usr/sbin/samba_kcc
Example: samba kcc command = /usr/local/bin/kcc
security (G)
This option affects how clients respond to Samba and is one of the most important
settings in the smb.conf file.
Unless server role is specified, the default is security = user, as this is the most
common setting, used for a standalone file server or a DC.
The alternatives to security = user are security = ads or security = domain, which
support joining Samba to a Windows domain
You should use security = user and map to guest if you want to mainly setup shares
without a password (guest shares). This is commonly used for a shared printer server.
The different settings will now be explained.
SECURITY = AUTO
This is the default security setting in Samba, and causes Samba to consult the server
role parameter (if set) to determine the security mode.
SECURITY = USER
If server role is not specified, this is the default security setting in Samba. With
user-level security a client must first "log-on" with a valid username and password
(which can be mapped using the username map parameter). Encrypted passwords (see the
encrypt passwords parameter) can also be used in this security mode. Parameters such
as force user and guest only if set are then applied and may change the UNIX user to
use on this connection, but only after the user has been successfully authenticated.
Note that the name of the resource being requested is not sent to the server until
after the server has successfully authenticated the client. This is why guest shares
don't work in user level security without allowing the server to automatically map
unknown users into the guest account. See the map to guest parameter for details on
doing this.
SECURITY = DOMAIN
This mode will only work correctly if net(8) has been used to add this machine into a
Windows NT Domain. It expects the encrypt passwords parameter to be set to yes. In
this mode Samba will try to validate the username/password by passing it to a Windows
NT Primary or Backup Domain Controller, in exactly the same way that a Windows NT
Server would do.
Note that a valid UNIX user must still exist as well as the account on the Domain
Controller to allow Samba to have a valid UNIX account to map file access to.
Note that from the client's point of view security = domain is the same as security =
user. It only affects how the server deals with the authentication, it does not in any
way affect what the client sees.
Note that the name of the resource being requested is not sent to the server until
after the server has successfully authenticated the client. This is why guest shares
don't work in user level security without allowing the server to automatically map
unknown users into the guest account. See the map to guest parameter for details on
doing this.
See also the password server parameter and the encrypt passwords parameter.
SECURITY = ADS
In this mode, Samba will act as a domain member in an ADS realm. To operate in this
mode, the machine running Samba will need to have Kerberos installed and configured
and Samba will need to be joined to the ADS realm using the net utility.
Note that this mode does NOT make Samba operate as a Active Directory Domain
Controller.
Note that this forces require strong key = yes and client schannel = yes for the
primary domain.
Read the chapter about Domain Membership in the HOWTO for details.
Default: security = AUTO
Example: security = DOMAIN
security mask (S)
This parameter has been removed for Samba 4.0.0.
No default
server addresses (S)
This is a per-share parameter to limit share visibility and accessibility to specific
server IP addresses. Multi-homed servers can offer a different set of shares per
interface.
An empty list means to offer a share on all interfaces.
Default: server addresses =
max protocol
This parameter is a synonym for server max protocol.
protocol
This parameter is a synonym for server max protocol.
server max protocol (G)
The value of the parameter (a string) is the highest protocol level that will be
supported by the server.
Possible values are :
• LANMAN1: First modern version of the protocol. Long filename support.
• LANMAN2: Updates to Lanman1 protocol.
• NT1: Current up to date version of the protocol. Used by Windows NT. Known
as CIFS.
• SMB2: Re-implementation of the SMB protocol. Used by Windows Vista and
later versions of Windows. SMB2 has sub protocols available.
• SMB2_02: The earliest SMB2 version.
• SMB2_10: Windows 7 SMB2 version.
By default SMB2 selects the SMB2_10 variant.
• SMB3: The same as SMB2. Used by Windows 8. SMB3 has sub protocols
available.
• SMB3_00: Windows 8 SMB3 version.
• SMB3_02: Windows 8.1 SMB3 version.
• SMB3_11: Windows 10 SMB3 version.
By default SMB3 selects the SMB3_11 variant.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol.
Default: server max protocol = SMB3
Example: server max protocol = LANMAN1
min protocol
This parameter is a synonym for server min protocol.
server min protocol (G)
This setting controls the minimum protocol version that the server will allow the
client to use.
Normally this option should not be set as the automatic negotiation phase in the SMB
protocol takes care of choosing the appropriate protocol unless you have legacy
clients which are SMB1 capable only.
See Related command: server max protocol for a full list of available protocols.
Default: server min protocol = SMB2_02
Example: server min protocol = NT1
server multi channel support (G)
This boolean parameter controls whether smbd(8) will support SMB3 multi-channel.
This parameter was added with version 4.4.
Note that this feature was still considered experimental up to 4.14.
Due to dependencies to kernel APIs of Linux or FreeBSD, it's only possible to use this
feature on Linux and FreeBSD for now. For testing this restriction can be overwritten
by specifying force:server multi channel support=yes in addition.
This option is enabled by default starting with to 4.15 (on Linux and FreeBSD).
Default: server multi channel support = yes
server role (G)
This option determines the basic operating mode of a Samba server and is one of the
most important settings in the smb.conf file.
The default is server role = auto, as causes Samba to operate according to the
security setting, or if not specified as a simple file server that is not connected to
any domain.
The alternatives are server role = standalone or server role = member server, which
support joining Samba to a Windows domain, along with server role = domain controller,
which run Samba as a Windows domain controller.
You should use server role = standalone and map to guest if you want to mainly setup
shares without a password (guest shares). This is commonly used for a shared printer
server.
SERVER ROLE = AUTO
This is the default server role in Samba, and causes Samba to consult the security
parameter (if set) to determine the server role, giving compatible behaviours to
previous Samba versions.
SERVER ROLE = STANDALONE
If security is also not specified, this is the default security setting in Samba. In
standalone operation, a client must first "log-on" with a valid username and password
(which can be mapped using the username map parameter) stored on this machine.
Encrypted passwords (see the encrypt passwords parameter) are by default used in this
security mode. Parameters such as force user and guest only if set are then applied
and may change the UNIX user to use on this connection, but only after the user has
been successfully authenticated.
SERVER ROLE = MEMBER SERVER
This mode will only work correctly if net(8) has been used to add this machine into a
Windows Domain. It expects the encrypt passwords parameter to be set to yes. In this
mode Samba will try to validate the username/password by passing it to a Windows or
Samba Domain Controller, in exactly the same way that a Windows Server would do.
Note that a valid UNIX user must still exist as well as the account on the Domain
Controller to allow Samba to have a valid UNIX account to map file access to. Winbind
can provide this.
SERVER ROLE = CLASSIC PRIMARY DOMAIN CONTROLLER
This mode of operation runs a classic Samba primary domain controller, providing
domain logon services to Windows and Samba clients of an NT4-like domain. Clients must
be joined to the domain to create a secure, trusted path across the network. There
must be only one PDC per NetBIOS scope (typically a broadcast network or clients
served by a single WINS server).
SERVER ROLE = CLASSIC BACKUP DOMAIN CONTROLLER
This mode of operation runs a classic Samba backup domain controller, providing domain
logon services to Windows and Samba clients of an NT4-like domain. As a BDC, this
allows multiple Samba servers to provide redundant logon services to a single NetBIOS
scope.
SERVER ROLE = ACTIVE DIRECTORY DOMAIN CONTROLLER
This mode of operation runs Samba as an active directory domain controller, providing
domain logon services to Windows and Samba clients of the domain. This role requires
special configuration, see the Samba4 HOWTO
SERVER ROLE = IPA DOMAIN CONTROLLER
This mode of operation runs Samba in a hybrid mode for IPA domain controller,
providing forest trust to Active Directory. This role requires special configuration
performed by IPA installers and should not be used manually by any administrator.
Default: server role = AUTO
Example: server role = ACTIVE DIRECTORY DOMAIN CONTROLLER
server schannel (G)
This option is deprecated and will be removed in future, as it is a security problem
if not set to "yes" (which will be the hardcoded behavior in future).
Avoid using this option! Use explicit 'server require schannel:COMPUTERACCOUNT = no'
instead!
Samba will log an error in the log files at log level 0 if legacy a client is rejected
or allowed without an explicit, 'server require schannel:COMPUTERACCOUNT = no' option
for the client. The message will indicate the explicit 'server require
schannel:COMPUTERACCOUNT = no' line to be added, if the legacy client software
requires it. (The log level can be adjusted with 'CVE_2020_1472:error_debug_level = 1'
in order to complain only at a higher log level).
This allows admins to use "auto" only for a short grace period, in order to collect
the explicit 'server require schannel:COMPUTERACCOUNT = no' options.
See CVE-2020-1472(ZeroLogon), https://bugzilla.samba.org/show_bug.cgi?id=14497.
This option is over-ridden by the server require schannel:COMPUTERACCOUNT option.
This option is over-ridden by the effective value of 'yes' from the 'server schannel
require seal:COMPUTERACCOUNT' and/or 'server schannel require seal' options.
Default: server schannel = yes
server require schannel:COMPUTERACCOUNT (G)
If you still have legacy domain members, which required "server schannel = auto"
before, it is possible to specify explicit exception per computer account by using
'server require schannel:COMPUTERACCOUNT = no' as option. Note that COMPUTERACCOUNT
has to be the sAMAccountName value of the computer account (including the trailing '$'
sign).
Samba will complain in the log files at log level 0, about the security problem if the
option is not set to "no", but the related computer is actually using the netlogon
secure channel (schannel) feature. (The log level can be adjusted with
'CVE_2020_1472:warn_about_unused_debug_level = 1' in order to complain only at a
higher log level).
Samba will warn in the log files at log level 5, if a setting is still needed for the
specified computer account.
See CVE-2020-1472(ZeroLogon), https://bugzilla.samba.org/show_bug.cgi?id=14497.
This option overrides the server schannel option.
This option is over-ridden by the effective value of 'yes' from the 'server schannel
require seal:COMPUTERACCOUNT' and/or 'server schannel require seal' options.
Which means 'server require schannel:COMPUTERACCOUNT = no' is only useful in
combination with 'server schannel require seal:COMPUTERACCOUNT = no'
server require schannel:LEGACYCOMPUTER1$ = no
server require schannel seal:LEGACYCOMPUTER1$ = no
server require schannel:NASBOX$ = no
server require schannel seal:NASBOX$ = no
server require schannel:LEGACYCOMPUTER2$ = no
server require schannel seal:LEGACYCOMPUTER2$ = no
No default
server schannel require seal (G)
This option is deprecated and will be removed in future, as it is a security problem
if not set to "yes" (which will be the hardcoded behavior in future).
This option controls whether the netlogon server, will reject the usage of netlogon
secure channel without privacy/enryption.
The option is modelled after the registry key available on Windows.
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netlogon\Parameters\RequireSeal=2
Avoid using this option! Use the per computer account specific option 'server
schannel require seal:COMPUTERACCOUNT' instead! Which is available with the patches
for CVE-2022-38023 see https://bugzilla.samba.org/show_bug.cgi?id=15240.
Samba will log an error in the log files at log level 0 if legacy a client is rejected
or allowed without an explicit, 'server schannel require seal:COMPUTERACCOUNT = no'
option for the client. The message will indicate the explicit 'server schannel require
seal:COMPUTERACCOUNT = no' line to be added, if the legacy client software requires
it. (The log level can be adjusted with 'CVE_2022_38023:error_debug_level = 1' in
order to complain only at a higher log level).
This allows admins to use "no" only for a short grace period, in order to collect the
explicit 'server schannel require seal:COMPUTERACCOUNT = no' options.
When set to 'yes' this option overrides the 'server require schannel:COMPUTERACCOUNT'
and 'server schannel' options and implies 'server require schannel:COMPUTERACCOUNT =
yes'.
This option is over-ridden by the server schannel require seal:COMPUTERACCOUNT option.
Default: server schannel require seal = yes
server schannel require seal:COMPUTERACCOUNT (G)
If you still have legacy domain members, which required "server schannel require seal
= no" before, it is possible to specify explicit exception per computer account by
using 'server schannel require seal:COMPUTERACCOUNT = no' as option. Note that
COMPUTERACCOUNT has to be the sAMAccountName value of the computer account (including
the trailing '$' sign).
Samba will log a complaint in the log files at log level 0 about the security problem
if the option is set to "no", but the related computer does not require it. (The log
level can be adjusted with 'CVE_2022_38023:warn_about_unused_debug_level = 1' in order
to complain only at a higher log level).
Samba will warn in the log files at log level 5, if a setting is still needed for the
specified computer account.
See CVE-2022-38023, https://bugzilla.samba.org/show_bug.cgi?id=15240.
This option overrides the 'server schannel require seal' option.
When set to 'yes' this option overrides the 'server require schannel:COMPUTERACCOUNT'
and 'server schannel' options and implies 'server require schannel:COMPUTERACCOUNT =
yes'.
server require schannel seal:LEGACYCOMPUTER1$ = no
server require schannel seal:NASBOX$ = no
server require schannel seal:LEGACYCOMPUTER2$ = no
No default
server services (G)
This option contains the services that the Samba daemon will run.
An entry in the smb.conf file can either override the previous value completely or
entries can be removed from or added to it by prefixing them with + or -.
Default: server services = s3fs, rpc, nbt, wrepl, ldap, cldap, kdc, drepl, winbindd,
ntp_signd, kcc, dnsupdate, dns
Example: server services = -s3fs, +smb
server signing (G)
This controls whether the client is allowed or required to use SMB1 and SMB2 signing.
Possible values are default, auto, mandatory and disabled.
By default, and when smb signing is set to default, smb signing is required when
server role is active directory domain controller and disabled otherwise.
When set to auto, SMB1 signing is offered, but not enforced. When set to mandatory,
SMB1 signing is required and if set to disabled, SMB signing is not offered either.
For the SMB2 protocol, by design, signing cannot be disabled. In the case where SMB2
is negotiated, if this parameter is set to disabled, it will be treated as auto.
Setting it to mandatory will still require SMB2 clients to use signing.
Default: server signing = default
server smb encrypt (S)
This parameter controls whether a remote client is allowed or required to use SMB
encryption. It has different effects depending on whether the connection uses SMB1 or
SMB2 and newer:
• If the connection uses SMB1, then this option controls the use of a
Samba-specific extension to the SMB protocol introduced in Samba 3.2 that
makes use of the Unix extensions.
• If the connection uses SMB2 or newer, then this option controls the use of
the SMB-level encryption that is supported in SMB version 3.0 and above and
available in Windows 8 and newer.
This parameter can be set globally and on a per-share bases. Possible values are off,
if_required, desired, and required. A special value is default which is the implicit
default setting of if_required.
Effects for SMB1
The Samba-specific encryption of SMB1 connections is an extension to the SMB
protocol negotiated as part of the UNIX extensions. SMB encryption uses the GSSAPI
(SSPI on Windows) ability to encrypt and sign every request/response in a SMB
protocol stream. When enabled it provides a secure method of SMB/CIFS
communication, similar to an ssh protected session, but using SMB/CIFS
authentication to negotiate encryption and signing keys. Currently this is only
supported smbclient of by Samba 3.2 and newer, and hopefully soon Linux CIFSFS and
MacOS/X clients. Windows clients do not support this feature.
This may be set on a per-share basis, but clients may chose to encrypt the entire
session, not just traffic to a specific share. If this is set to mandatory then
all traffic to a share must be encrypted once the connection has been made to the
share. The server would return "access denied" to all non-encrypted requests on
such a share. Selecting encrypted traffic reduces throughput as smaller packet
sizes must be used (no huge UNIX style read/writes allowed) as well as the
overhead of encrypting and signing all the data.
If SMB encryption is selected, Windows style SMB signing (see the server signing
option) is no longer necessary, as the GSSAPI flags use select both signing and
sealing of the data.
When set to auto or default, SMB encryption is offered, but not enforced. When set
to mandatory, SMB encryption is required and if set to disabled, SMB encryption
can not be negotiated.
Effects for SMB2 and newer
Native SMB transport encryption is available in SMB version 3.0 or newer. It is
only offered by Samba if server max protocol is set to SMB3 or newer. Clients
supporting this type of encryption include Windows 8 and newer, Windows server
2012 and newer, and smbclient of Samba 4.1 and newer.
The protocol implementation offers various options:
• The capability to perform SMB encryption can be negotiated during
protocol negotiation.
• Data encryption can be enabled globally. In that case, an
encryption-capable connection will have all traffic in all its sessions
encrypted. In particular all share connections will be encrypted.
• Data encryption can also be enabled per share if not enabled globally.
For an encryption-capable connection, all connections to an
encryption-enabled share will be encrypted.
• Encryption can be enforced. This means that session setups will be
denied on non-encryption-capable connections if data encryption has
been enabled globally. And tree connections will be denied for
non-encryption capable connections to shares with data encryption
enabled.
These features can be controlled with settings of server smb encrypt as follows:
• Leaving it as default, explicitly setting default, or setting it to
if_required globally will enable negotiation of encryption but will not
turn on data encryption globally or per share.
• Setting it to desired globally will enable negotiation and will turn on
data encryption on sessions and share connections for those clients
that support it.
• Setting it to required globally will enable negotiation and turn on
data encryption on sessions and share connections. Clients that do not
support encryption will be denied access to the server.
• Setting it to off globally will completely disable the encryption
feature for all connections. Setting server smb encrypt = required for
individual shares (while it's globally off) will deny access to this
shares for all clients.
• Setting it to desired on a share will turn on data encryption for this
share for clients that support encryption if negotiation has been
enabled globally.
• Setting it to required on a share will enforce data encryption for this
share if negotiation has been enabled globally. I.e. clients that do
not support encryption will be denied access to the share.
Note that this allows per-share enforcing to be controlled in Samba
differently from Windows: In Windows, RejectUnencryptedAccess is a
global setting, and if it is set, all shares with data encryption
turned on are automatically enforcing encryption. In order to achieve
the same effect in Samba, one has to globally set server smb encrypt to
if_required, and then set all shares that should be encrypted to
required. Additionally, it is possible in Samba to have some shares
with encryption required and some other shares with encryption only
desired, which is not possible in Windows.
• Setting it to off or if_required for a share has no effect.
Default: server smb encrypt = default
server smb3 encryption algorithms (G)
This parameter specifies the availability and order of encryption algorithms which are
available for negotiation in the SMB3_11 dialect.
It is also possible to remove individual algorithms from the default list, by
prefixing them with '-'. This can avoid having to specify a hardcoded list.
Note: that the removal of AES-128-CCM from the list will result in SMB3_00 and SMB3_02
being unavailable, as it is the default and only available algorithm for these
dialects.
Default: server smb3 encryption algorithms = AES-128-GCM, AES-128-CCM, AES-256-GCM,
AES-256-CCM
Example: server smb3 encryption algorithms = AES-256-GCM
Example: server smb3 encryption algorithms = -AES-128-GCM -AES-128-CCM
server smb3 signing algorithms (G)
This parameter specifies the availability and order of signing algorithms which are
available for negotiation in the SMB3_11 dialect.
It is also possible to remove individual algorithms from the default list, by
prefixing them with '-'. This can avoid having to specify a hardcoded list.
Note: that the removal of AES-128-CMAC from the list will result in SMB3_00 and
SMB3_02 being unavailable, and the removal of HMAC-SHA256 will result in SMB2_02 and
SMB2_10 being unavailable, as these are the default and only available algorithms for
these dialects.
Default: server smb3 signing algorithms = AES-128-GMAC, AES-128-CMAC, HMAC-SHA256
Example: server smb3 signing algorithms = AES-128-CMAC, HMAC-SHA256
Example: server smb3 signing algorithms = -AES-128-CMAC
server string (G)
This controls what string will show up in the printer comment box in print manager and
next to the IPC connection in net view. It can be any string that you wish to show to
your users.
It also sets what will appear in browse lists next to the machine name.
A %v will be replaced with the Samba version number.
A %h will be replaced with the hostname.
Default: server string = Samba %v
Example: server string = University of GNUs Samba Server
set primary group script (G)
Thanks to the Posix subsystem in NT a Windows User has a primary group in addition to
the auxiliary groups. This script sets the primary group in the unix user database
when an administrator sets the primary group from the windows user manager or when
fetching a SAM with net rpc vampire. %u will be replaced with the user whose primary
group is to be set. %g will be replaced with the group to set.
Default: set primary group script =
Example: set primary group script = /usr/sbin/usermod -g '%g' '%u'
set quota command (G)
The set quota command should only be used whenever there is no operating system API
available from the OS that samba can use.
This option is only available if Samba was compiled with quota support.
This parameter should specify the path to a script that can set quota for the
specified arguments.
The specified script should take the following arguments:
• 1 - path to where the quota needs to be set. This needs to be interpreted
relative to the current working directory that the script may also check
for.
• 2 - quota type
• 1 - user quotas
• 2 - user default quotas (uid = -1)
• 3 - group quotas
• 4 - group default quotas (gid = -1)
• 3 - id (uid for user, gid for group, -1 if N/A)
• 4 - quota state (0 = disable, 1 = enable, 2 = enable and enforce)
• 5 - block softlimit
• 6 - block hardlimit
• 7 - inode softlimit
• 8 - inode hardlimit
• 9(optional) - block size, defaults to 1024
The script should output at least one line of data on success. And nothing on failure.
Default: set quota command =
Example: set quota command = /usr/local/sbin/set_quota
share:fake_fscaps (G)
This is needed to support some special application that makes QFSINFO calls to check
whether we set the SPARSE_FILES bit (0x40). If this bit is not set that particular
application refuses to work against Samba. With share:fake_fscaps = 64 the
SPARSE_FILES file system capability flag is set. Use other decimal values to specify
the bitmask you need to fake.
Default: share:fake_fscaps = 0
short preserve case (S)
This boolean parameter controls if new files which conform to 8.3 syntax, that is all
in upper case and of suitable length, are created upper case, or if they are forced to
be the default case. This option can be use with preserve case = yes to permit long
filenames to retain their case, while short names are lowered.
See the section on NAME MANGLING.
Default: short preserve case = yes
show add printer wizard (G)
With the introduction of MS-RPC based printing support for Windows NT/2000 client in
Samba 2.2, a "Printers..." folder will appear on Samba hosts in the share listing.
Normally this folder will contain an icon for the MS Add Printer Wizard (APW).
However, it is possible to disable this feature regardless of the level of privilege
of the connected user.
Under normal circumstances, the Windows NT/2000 client will open a handle on the
printer server with OpenPrinterEx() asking for Administrator privileges. If the user
does not have administrative access on the print server (i.e is not root or has
granted the SePrintOperatorPrivilege), the OpenPrinterEx() call fails and the client
makes another open call with a request for a lower privilege level. This should
succeed, however the APW icon will not be displayed.
Disabling the show add printer wizard parameter will always cause the OpenPrinterEx()
on the server to fail. Thus the APW icon will never be displayed.
Note
This does not prevent the same user from having administrative privilege on an
individual printer.
Default: show add printer wizard = yes
shutdown script (G)
This a full path name to a script called by smbd(8) that should start a shutdown
procedure.
If the connected user possesses the SeRemoteShutdownPrivilege, right, this command
will be run as root.
The %z %t %r %f variables are expanded as follows:
• %z will be substituted with the shutdown message sent to the server.
• %t will be substituted with the number of seconds to wait before
effectively starting the shutdown procedure.
• %r will be substituted with the switch -r. It means reboot after shutdown
for NT.
• %f will be substituted with the switch -f. It means force the shutdown even
if applications do not respond for NT.
Shutdown script example:
#!/bin/bash
time=$2
let time="${time} / 60"
let time="${time} + 1"
/sbin/shutdown $3 $4 +$time $1 &
Shutdown does not return so we need to launch it in background.
Default: shutdown script =
Example: shutdown script = /usr/local/samba/sbin/shutdown %m %t %r %f
unix extensions
This parameter is a synonym for smb1 unix extensions.
smb1 unix extensions (G)
This boolean parameter controls whether Samba implements the SMB1/CIFS UNIX
extensions, as defined by HP. These extensions enable Samba to better serve UNIX
SMB1/CIFS clients by supporting features such as symbolic links, hard links, etc...
These extensions require a similarly enabled client, and are of no current use to
Windows clients.
Note if this parameter is turned on, the wide links parameter will automatically be
disabled.
See the parameter allow insecure wide links if you wish to change this coupling
between the two parameters.
Default: smb1 unix extensions = yes
smb2 disable lock sequence checking (G)
This boolean parameter controls whether smbd(8) will disable lock sequence checking
even for multi-channel connections as well as durable handles.
The [MS-SMB2] specification (under 3.3.5.14 Receiving an SMB2 LOCK Request) documents
that a server should do lock sequence if Open.IsResilient or Open.IsDurable or
Open.IsPersistent is TRUE or if Connection.Dialect belongs to the SMB 3.x dialect
family and Connection.ServerCapabilities includes SMB2_GLOBAL_CAP_MULTI_CHANNEL.
But Windows Server (at least up to v2004) only does these checks for the
Open.IsResilient and Open.IsPersistent. That means they do not implement the behavior
specified in [MS-SMB2].
By default Samba behaves according to the specification and implements lock sequence
checking when multi-channel is used.
Warning: Only enable this option if existing clients can't handle lock sequence
checking for handles without Open.IsResilient and Open.IsPersistent. And it turns out
that the Windows Server behavior is required.
Note: it's likely that this option will be removed again if future Windows versions
change their behavior.
Note: Samba does not implement Open.IsResilient and Open.IsPersistent yet.
Default: smb2 disable lock sequence checking = no
Example: smb2 disable lock sequence checking = yes
smb2 disable oplock break retry (G)
This boolean parameter controls whether smbd(8) will trigger smb2 oplock break
notification retries when using server multi channel support = yes.
The [MS-SMB2] specification documents that a server should send smb2 oplock break
notification retries on all available channel to the given client.
But Windows Server versions (at least up to 2019) do not send smb2 oplock break
notification retries on channel failures. That means they do not implement the
behavior specified in [MS-SMB2].
By default Samba behaves according to the specification and send smb2 oplock break
notification retries.
Warning: Only enable this option if existing clients can't handle possible retries and
it turns out that the Windows Server behavior is required.
Note: it's likely that this option gets removed again if future Windows versions
change their behavior.
Note: this only applies to oplocks and not SMB2 leases.
Default: smb2 disable oplock break retry = no
Example: smb2 disable oplock break retry = yes
smb2 leases (G)
This boolean option tells smbd whether to globally negotiate SMB2 leases on file open
requests. Leasing is an SMB2-only feature which allows clients to aggressively cache
files locally above and beyond the caching allowed by SMB1 oplocks.
This is only available with oplocks = yes and kernel oplocks = no.
Default: smb2 leases = yes
smb2 max credits (G)
This option controls the maximum number of outstanding simultaneous SMB2 operations
that Samba tells the client it will allow. This is similar to the max mux parameter
for SMB1. You should never need to set this parameter.
The default is 8192 credits, which is the same as a Windows 2008R2 SMB2 server.
Default: smb2 max credits = 8192
smb2 max read (G)
This option specifies the protocol value that smbd(8) will return to a client,
informing the client of the largest size that may be returned by a single SMB2 read
call.
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect
(64KiB for SMB == 2.0, 8MiB for SMB >= 2.1 with LargeMTU). Large MTU is not supported
over NBT (tcp port 139).
Default: smb2 max read = 8388608
smb2 max trans (G)
This option specifies the protocol value that smbd(8) will return to a client,
informing the client of the largest size of buffer that may be used in querying file
meta-data via QUERY_INFO and related SMB2 calls.
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect
(64KiB for SMB == 2.0, 1MiB for SMB >= 2.1 with LargeMTU). Large MTU is not supported
over NBT (tcp port 139).
Default: smb2 max trans = 8388608
smb2 max write (G)
This option specifies the protocol value that smbd(8) will return to a client,
informing the client of the largest size that may be sent to the server by a single
SMB2 write call.
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect
(64KiB for SMB == 2.0, 8MiB for SMB => 2.1 with LargeMTU). Large MTU is not supported
over NBT (tcp port 139).
Default: smb2 max write = 8388608
smb3 share cap:CONTINUOUS AVAILABILITY (S)
The SMB3 protocol introduced the SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY flag. It means
clients can have different expectations from the server (or cluster of servers).
Note: this option only applies to disk shares.
In a ctdb cluster shares are continuously available, but windows clients mix this with
the global persistent handles support.
Persistent handles are requested if SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY is present
even without SMB2_CAP_PERSISTENT_HANDLES.
And SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY is required for SMB2_SHARE_CAP_CLUSTER to
have an effect.
So we better don't announce this by default until we support persistent handles.
The smb3 share cap:CONTINUOUS AVAILABILITY option can be used to force the
announcement of SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY.
Warning: only use this if you know what you are doing!
smb3 share cap:CONTINUOUS AVAILABILITY = yes
No default
smb3 share cap:SCALE OUT (S)
The SMB3 protocol introduced the SMB2_SHARE_CAP_SCALEOUT flag. It means clients can
have different expectations from cluster of multiple servers and alters the
retry/reconnect behavior.
Note: this option only applies to disk shares.
In a ctdb cluster we have multiple active nodes, so we announce
SMB2_SHARE_CAP_SCALEOUT in a cluster.
The smb3 share cap:SCALE OUT option can be used to disable the announcement of
SMB2_SHARE_CAP_SCALEOUT, even if clustering is yes.
clustering = yes
smb3 share cap: SCALE OUT = no
No default
smb3 share cap:CLUSTER (S)
The SMB3 protocol introduced the SMB2_SHARE_CAP_CLUSTER flag. It means clients can
expect that all cluster nodes provide a witness service in order to use the [MS-SWN]
protocol to monitor the server cluster.
Note: this option only applies to disk shares.
rpcd_witness is only active if samba-dcerpcd(8) is not started as on demand helper and
only in a ctdb cluster.
So we announce SMB2_SHARE_CAP_CLUSTER only if clustering is yes and rpc start on
demand helpers is no.
The smb3 share cap:SCALE OUT option can be used to control the announcement of
SMB2_SHARE_CAP_CLUSTER independent of clustering and rpc start on demand helpers.
Example to disable the announcement of SMB2_SHARE_CAP_CLUSTER:
clustering = yes
rpc start on demand helpers = no
smb3 share cap: CLUSTER = no
Example to force the announcement of SMB2_SHARE_CAP_CLUSTER:
smb3 share cap: CLUSTER = yes
Example to let Windows clients use the witness service, see smb3 share cap:CONTINUOUS
AVAILABILITY option and USE AT YOUR OWN RISK!:
clustering = yes
rpc start on demand helpers = no
# This is the default with the above:
# smb3 share cap: CLUSTER = yes
#
# Use at you own risk!
smb3 share cap: CONTINUOUS AVAILABILITY = yes
No default
smb3 share cap:ASYMMETRIC (S)
The SMB3_02 protocol introduced the SMB2_SHARE_CAP_ASYMMETRIC flag. It means clients
alters its behavior and uses isolated transport connections and witness registrations
for the share. It means a client may connect to different cluster nodes for individual
shares and net witness share-move can be used to control the node usage.
Note: this option only applies to disk shares.
Shares in a ctdb cluster are symmetric by design, so we don't announce
SMB2_SHARE_CAP_ASYMMETRIC by default.
The smb3 share cap:ASYMMETRIC option can be used to force the announcement of
SMB2_SHARE_CAP_ASYMMETRIC.
Example to force the announcement of SMB2_SHARE_CAP_ASYMMETRIC:
smb3 share cap: ASYMMETRIC = yes
Example to let Windows clients use the witness service, see smb3 share cap:CONTINUOUS
AVAILABILITY option and USE AT YOUR OWN RISK!:
clustering = yes
rpc start on demand helpers = no
# This is the default with the above:
# smb3 share cap: CLUSTER = yes
#
# Use at you own risk!
smb3 share cap: CONTINUOUS AVAILABILITY = yes
smb3 share cap: ASYMMETRIC = yes
No default
smb3 unix extensions (S)
Experimental SMB 3.1.1 Unix Extensions.
Default: smb3 unix extensions = no
smbd async dosmode (S)
This parameter control whether the fileserver will use sync or async methods for
fetching the DOS attributes when doing a directory listing. By default sync methods
will be used.
Default: smbd async dosmode = no
smbd getinfo ask sharemode (S)
This parameter allows disabling fetching file write time from the open file handle
database locking.tdb when a client requests file or directory metadata. It's a
performance optimisation at the expense of protocol correctness.
Default: smbd getinfo ask sharemode = yes
smbd max async dosmode (S)
This parameter controls how many async operations to fetch the DOS attributes the
fileserver will queue when doing directory listings.
Default: smbd max async dosmode = aio max threads * 2
smbd max xattr size (S)
This parameter controls the maximum size of extended attributes that may be written to
the server as EAs or as alternate data streams if vfs_streams_xattr is enabled. The
maximum size of extended attributes depends on the Samba server's operating system and
the underlying filesystem. The Linux VFS currently sets an upper boundary of 64 KiB
per extended attribute. FreeBSD does not set a practical upper limit, but since
pread() and pwrite() are not possible via the extattr on FreeBSD, it is not
recommended to increase this value above a few MiB. If a client attempts to write an
overly-large alternate datastream, the Samba server will return
STATUS_FILESYSTEM_LIMITATION. If this error is encountered, users may try increasing
the maximum size supported for xattr writes. If this is not possible, and writes are
from a MacOS client and to an AFP_Resource extended attribute, the user may enable the
vfs_fruit module and configure to allow stream writes for AFP_Resource to an
alternative storage location. See vfs_fruit documentation for further details.
Default: smbd max xattr size = 65536
smbd profiling level (G)
This parameter allows the administrator to enable profiling support.
Possible values are off, count and on.
Default: smbd profiling level = off
Example: smbd profiling level = on
smbd search ask sharemode (S)
This parameter allows disabling fetching file write time from the open file handle
database locking.tdb. It's a performance optimisation at the expense of protocol
correctness.
Default: smbd search ask sharemode = yes
smb encrypt (S)
This is a synonym for server smb encrypt.
Default: smb encrypt = default
smb passwd file (G)
This option sets the path to the encrypted smbpasswd file. By default the path to the
smbpasswd file is compiled into Samba.
An example of use is:
smb passwd file = /etc/samba/smbpasswd
Default: smb passwd file = /etc/samba/smbpasswd
smb ports (G)
Specifies which ports the server should listen on for SMB traffic.
Default: smb ports = 445 139
socket options (G)
Warning
Modern server operating systems are tuned for high network performance in the
majority of situations; when you set socket options you are overriding those
settings. Linux in particular has an auto-tuning mechanism for buffer sizes that
will be disabled if you specify a socket buffer size. This can potentially cripple
your TCP/IP stack.
Getting the socket options correct can make a big difference to your performance,
but getting them wrong can degrade it by just as much. As with any other low level
setting, if you must make changes to it, make small changes and test the effect
before making any large changes.
This option allows you to set socket options to be used when talking with the client.
Socket options are controls on the networking layer of the operating systems which
allow the connection to be tuned.
This option will typically be used to tune your Samba server for optimal performance
for your local network. There is no way that Samba can know what the optimal
parameters are for your net, so you must experiment and choose them yourself. We
strongly suggest you read the appropriate documentation for your operating system
first (perhaps man setsockopt will help).
You may find that on some systems Samba will say "Unknown socket option" when you
supply an option. This means you either incorrectly typed it or you need to add an
include file to includes.h for your OS. If the latter is the case please send the
patch to samba-technical@lists.samba.org.
Any of the supported socket options may be combined in any way you like, as long as
your OS allows it.
This is the list of socket options currently settable using this option:
• SO_KEEPALIVE
• SO_REUSEADDR
• SO_BROADCAST
• TCP_NODELAY
• TCP_KEEPCNT *
• TCP_KEEPIDLE *
• TCP_KEEPINTVL *
• IPTOS_LOWDELAY
• IPTOS_THROUGHPUT
• SO_REUSEPORT
• SO_SNDBUF *
• SO_RCVBUF *
• SO_SNDLOWAT *
• SO_RCVLOWAT *
• SO_SNDTIMEO *
• SO_RCVTIMEO *
• TCP_FASTACK *
• TCP_QUICKACK
• TCP_NODELAYACK
• TCP_KEEPALIVE_THRESHOLD *
• TCP_KEEPALIVE_ABORT_THRESHOLD *
• TCP_DEFER_ACCEPT *
• TCP_USER_TIMEOUT *
Those marked with a '*' take an integer argument. The others can optionally take a 1
or 0 argument to enable or disable the option, by default they will be enabled if you
don't specify 1 or 0.
To specify an argument use the syntax SOME_OPTION = VALUE for example SO_SNDBUF =
8192. Note that you must not have any spaces before or after the = sign.
If you are on a local network then a sensible option might be:
socket options = IPTOS_LOWDELAY
If you have a local network then you could try:
socket options = IPTOS_LOWDELAY TCP_NODELAY
If you are on a wide area network then perhaps try setting IPTOS_THROUGHPUT.
Note that several of the options may cause your Samba server to fail completely. Use
these options with caution!
Default: socket options = TCP_NODELAY
Example: socket options = IPTOS_LOWDELAY
spn update command (G)
This option sets the command that for updating servicePrincipalName names from
spn_update_list.
Default: spn update command = /usr/sbin/samba_spnupdate
Example: spn update command = /usr/local/sbin/spnupdate
spoolss: architecture (G)
Windows spoolss print clients only allow association of server-side drivers with
printers when the driver architecture matches the advertised print server
architecture. Samba's spoolss print server architecture can be changed using this
parameter.
Default: spoolss: architecture = Windows x64
Example: spoolss: architecture = Windows NT x86
spoolss: os_major (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 5.0.2195 (Windows 2000). The example
is 6.1.7601 (Windows 2008 R2).
Default: spoolss: os_major = 5
Example: spoolss: os_major = 6
spoolss: os_minor (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 5.0.2195 (Windows 2000). The example
is 6.1.7601 (Windows 2008 R2).
Default: spoolss: os_minor = 0
Example: spoolss: os_minor = 1
spoolss: os_build (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 5.0.2195 (Windows 2000). The example
is 6.1.7601 (Windows 2008 R2).
Default: spoolss: os_build = 2195
Example: spoolss: os_build = 7601
spoolss_client: os_major (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 6.1.7007 (Windows 7 and Windows Server
2008 R2).
Default: spoolss_client: os_major = 6
spoolss_client: os_minor (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 6.1.7007 (Windows 7 and Windows Server
2008 R2).
Default: spoolss_client: os_minor = 1
spoolss_client: os_build (G)
Windows might require a new os version number. This option allows to modify the build
number. The complete default version number is: 6.1.7007 (Windows 7 and Windows Server
2008 R2).
Default: spoolss_client: os_build = 7007
spotlight (S)
This parameter controls whether Samba allows Spotlight queries on a share. For
controlling indexing of filesystems you also have to use Tracker's own configuration
system.
Spotlight has several prerequisites:
• Samba must be configured and built with Spotlight support.
• Tracker integration must be setup and the share must be indexed by Tracker.
For a detailed set of instructions please see
https://wiki.samba.org/index.php/Spotlight.
Default: spotlight = no
spotlight backend (S)
Spotlight search backend. Available backends:
• noindex - a backend that returns no results.
• tracker - Gnome Tracker.
• elasticsearch - a backend that uses JSON and REST over HTTP(s) to query an
Elasticsearch server.
Default: spotlight backend = noindex
stat cache (G)
This parameter determines if smbd(8) will use a cache in order to speed up case
insensitive name mappings. You should never need to change this parameter.
Default: stat cache = yes
state directory (G)
Usually, most of the TDB files are stored in the lock directory. Since Samba 3.4.0, it
is possible to differentiate between TDB files with persistent data and TDB files with
non-persistent data using the state directory and the cache directory options.
This option specifies the directory where TDB files containing important persistent
data will be stored.
Default: state directory = /var/lib/samba
Example: state directory = /var/run/samba/locks/state
store dos attributes (S)
If this parameter is set Samba attempts to first read DOS attributes (SYSTEM, HIDDEN,
ARCHIVE or READ-ONLY) from a filesystem extended attribute, before mapping DOS
attributes to UNIX permission bits (such as occurs with map hidden and map readonly).
When set, DOS attributes will be stored onto an extended attribute in the UNIX
filesystem, associated with the file or directory. When this parameter is set it will
override the parameters map hidden, map system, map archive and map readonly and they
will behave as if they were set to off. This parameter writes the DOS attributes as a
string into the extended attribute named "user.DOSATTRIB". This extended attribute is
explicitly hidden from smbd clients requesting an EA list. On Linux the filesystem
must have been mounted with the mount option user_xattr in order for extended
attributes to work, also extended attributes must be compiled into the Linux kernel.
In Samba 3.5.0 and above the "user.DOSATTRIB" extended attribute has been extended to
store the create time for a file as well as the DOS attributes. This is done in a
backwards compatible way so files created by Samba 3.5.0 and above can still have the
DOS attribute read from this extended attribute by earlier versions of Samba, but they
will not be able to read the create time stored there. Storing the create time
separately from the normal filesystem meta-data allows Samba to faithfully reproduce
NTFS semantics on top of a POSIX filesystem. The default has changed to yes in Samba
release 4.9.0 and above to allow better Windows fileserver compatibility in a default
install.
Default: store dos attributes = yes
strict allocate (S)
This is a boolean that controls the handling of disk space allocation in the server.
When this is set to yes the server will change from UNIX behaviour of not committing
real disk storage blocks when a file is extended to the Windows behaviour of actually
forcing the disk system to allocate real storage blocks when a file is created or
extended to be a given size. In UNIX terminology this means that Samba will stop
creating sparse files.
This option is really designed for file systems that support fast allocation of large
numbers of blocks such as extent-based file systems. On file systems that don't
support extents (most notably ext3) this can make Samba slower. When you work with
large files over >100MB on file systems without extents you may even run into problems
with clients running into timeouts.
When you have an extent based filesystem it's likely that we can make use of unwritten
extents which allows Samba to allocate even large amounts of space very fast and you
will not see any timeout problems caused by strict allocate. With strict allocate in
use you will also get much better out of quota messages in case you use quotas.
Another advantage of activating this setting is that it will help to reduce file
fragmentation.
To give you an idea on which filesystems this setting might currently be a good option
for you: XFS, ext4, btrfs, ocfs2 on Linux and JFS2 on AIX support unwritten extents.
On Filesystems that do not support it, preallocation is probably an expensive
operation where you will see reduced performance and risk to let clients run into
timeouts when creating large files. Examples are ext3, ZFS, HFS+ and most others, so
be aware if you activate this setting on those filesystems.
Default: strict allocate = no
strict locking (S)
This is an enumerated type that controls the handling of file locking in the server.
When this is set to yes, the server will check every read and write access for file
locks, and deny access if locks exist. This can be slow on some systems.
When strict locking is set to Auto (the default), the server performs file lock checks
only on non-oplocked files. As most Windows redirectors perform file locking checks
locally on oplocked files this is a good trade off for improved performance.
When strict locking is disabled, the server performs file lock checks only when the
client explicitly asks for them.
Well-behaved clients always ask for lock checks when it is important. So in the vast
majority of cases, strict locking = Auto or strict locking = no is acceptable.
Default: strict locking = Auto
strict rename (S)
By default a Windows SMB server prevents directory renames when there are open file or
directory handles below it in the filesystem hierarchy. Historically Samba has always
allowed this as POSIX filesystem semantics require it.
This boolean parameter allows Samba to match the Windows behavior. Setting this to
"yes" is a very expensive change, as it forces Samba to travers the entire open file
handle database on every directory rename request. In a clustered Samba system the
cost is even greater than the non-clustered case.
When set to "no" smbd only checks the local process the client is attached to for open
files below a directory being renamed, instead of checking for open files across all
smbd processes.
Because of the expense in fully searching the database, the default is "no", and it is
recommended to be left that way unless a specific Windows application requires it to
be changed.
If the client has requested UNIX extensions (POSIX pathnames) then renames are always
allowed and this parameter has no effect.
Default: strict rename = no
strict sync (S)
This parameter controls whether Samba honors a request from an SMB client to ensure
any outstanding operating system buffer contents held in memory are safely written
onto stable storage on disk. If set to yes, which is the default, then Windows
applications can force the smbd server to synchronize unwritten data onto the disk. If
set to no then smbd will ignore client requests to synchronize unwritten data onto
stable storage on disk.
In Samba 4.7.0, the default for this parameter changed from no to yes to better match
the expectations of SMB2/3 clients and improve application safety when running against
smbd.
The flush request from SMB2/3 clients is handled asynchronously inside smbd, so
leaving the parameter as the default value of yes does not block the processing of
other requests to the smbd process.
Legacy Windows applications (such as the Windows 98 explorer shell) seemed to confuse
writing buffer contents to the operating system with synchronously writing outstanding
data onto stable storage on disk. Changing this parameter to no means that smbd(8)
will ignore the Windows applications request to synchronize unwritten data onto disk.
Only consider changing this if smbd is serving obsolete SMB1 Windows clients prior to
Windows XP (Windows 98 and below). There should be no need to change this setting for
normal operations.
Default: strict sync = yes
svcctl list (G)
This option defines a list of init scripts that smbd will use for starting and
stopping Unix services via the Win32 ServiceControl API. This allows Windows
administrators to utilize the MS Management Console plug-ins to manage a Unix server
running Samba.
The administrator must create a directory name svcctl in Samba's $(libdir) and create
symbolic links to the init scripts in /etc/init.d/. The name of the links must match
the names given as part of the svcctl list.
Default: svcctl list =
Example: svcctl list = cups postfix portmap httpd
sync always (S)
This is a boolean parameter that controls whether writes will always be written to
stable storage before the write call returns. If this is no then the server will be
guided by the client's request in each write call (clients can set a bit indicating
that a particular write should be synchronous). If this is yes then every write will
be followed by a fsync() call to ensure the data is written to disk. Note that the
strict sync parameter must be set to yes in order for this parameter to have any
effect.
Default: sync always = no
syslog (G)
This parameter maps how Samba debug messages are logged onto the system syslog logging
levels. Samba debug level zero maps onto syslog LOG_ERR, debug level one maps onto
LOG_WARNING, debug level two maps onto LOG_NOTICE, debug level three maps onto
LOG_INFO. All higher levels are mapped to LOG_DEBUG.
This parameter sets the threshold for sending messages to syslog. Only messages with
debug level less than this value will be sent to syslog. There still will be some
logging to log.[sn]mbd even if syslog only is enabled.
The logging parameter should be used instead. When logging is set, it overrides the
syslog parameter.
Default: syslog = 1
syslog only (G)
If this parameter is set then Samba debug messages are logged into the system syslog
only, and not to the debug log files. There still will be some logging to log.[sn]mbd
even if syslog only is enabled.
The logging parameter should be used instead. When logging is set, it overrides the
syslog only parameter.
Default: syslog only = no
template homedir (G)
When filling out the user information for a Windows NT user, the winbindd(8) daemon
uses this parameter to fill in the home directory for that user. If the string %D is
present it is substituted with the user's Windows NT domain name. If the string %U is
present it is substituted with the user's Windows NT user name.
Default: template homedir = /home/%D/%U
template shell (G)
When filling out the user information for a Windows NT user, the winbindd(8) daemon
uses this parameter to fill in the login shell for that user.
Default: template shell = /bin/false
time server (G)
This parameter determines if nmbd(8) advertises itself as a time server to Windows
clients.
Default: time server = no
debug timestamp
This parameter is a synonym for timestamp logs.
timestamp logs (G)
Samba debug log messages are timestamped by default. If you are running at a high
debug level these timestamps can be distracting. This boolean parameter allows
timestamping to be turned off.
Default: timestamp logs = yes
tls cafile (G)
This option can be set to a file (PEM format) containing CA certificates of root CAs
to trust to sign certificates or intermediate CA certificates.
This path is relative to private dir if the path does not start with a /.
Default: tls cafile = tls/ca.pem
tls certfile (G)
This option can be set to a file (PEM format) containing the RSA certificate.
This path is relative to private dir if the path does not start with a /.
Default: tls certfile = tls/cert.pem
tls crlfile (G)
This option can be set to a file containing a certificate revocation list (CRL).
This path is relative to private dir if the path does not start with a /.
Default: tls crlfile =
tls dh params file (G)
This option can be set to a file with Diffie-Hellman parameters which will be used
with DH ciphers.
This path is relative to private dir if the path does not start with a /.
Default: tls dh params file =
tls enabled (G)
If this option is set to yes, then Samba will use TLS when possible in communication.
Default: tls enabled = yes
tls keyfile (G)
This option can be set to a file (PEM format) containing the RSA private key. This
file must be accessible without a pass-phrase, i.e. it must not be encrypted.
This path is relative to private dir if the path does not start with a /.
Default: tls keyfile = tls/key.pem
tls priority (G)
This option can be set to a string describing the TLS protocols to be supported in the
parts of Samba that use GnuTLS, specifically the AD DC.
The string is appended to the default priority list of GnuTLS.
The valid options are described in the GNUTLS Priority-Strings documentation at
http://gnutls.org/manual/html_node/Priority-Strings.html
The SSL3.0 protocol will be disabled.
Default: tls priority = NORMAL:-VERS-SSL3.0
tls verify peer (G)
This controls if and how strict the client will verify the peer's certificate and
name. Possible values are (in increasing order): no_check, ca_only,
ca_and_name_if_available, ca_and_name and as_strict_as_possible.
When set to no_check the certificate is not verified at all, which allows trivial man
in the middle attacks.
When set to ca_only the certificate is verified to be signed from a ca specified in
the tls ca file option. Setting tls ca file to a valid file is required. The
certificate lifetime is also verified. If the tls crl file option is configured, the
certificate is also verified against the ca crl.
When set to ca_and_name_if_available all checks from ca_only are performed. In
addition, the peer hostname is verified against the certificate's name, if it is
provided by the application layer and not given as an ip address string.
When set to ca_and_name all checks from ca_and_name_if_available are performed. In
addition the peer hostname needs to be provided and even an ip address is checked
against the certificate's name.
When set to as_strict_as_possible all checks from ca_and_name are performed. In
addition the tls crl file needs to be configured. Future versions of Samba may
implement additional checks.
Default: tls verify peer = as_strict_as_possible
unicode (G)
Specifies whether the server and client should support unicode.
If this option is set to false, the use of ASCII will be forced.
Default: unicode = yes
unix charset (G)
Specifies the charset the unix machine Samba runs on uses. Samba needs to know this in
order to be able to convert text to the charsets other SMB clients use.
This is also the charset Samba will use when specifying arguments to scripts that it
invokes.
Default: unix charset = UTF-8
Example: unix charset = ASCII
unix password sync (G)
This boolean parameter controls whether Samba attempts to synchronize the UNIX
password with the SMB password when the encrypted SMB password in the smbpasswd file
is changed. If this is set to yes the program specified in the passwd program
parameter is called AS ROOT - to allow the new UNIX password to be set without access
to the old UNIX password (as the SMB password change code has no access to the old
password cleartext, only the new).
This option has no effect if samba is running as an active directory domain
controller, in that case have a look at the password hash gpg key ids option and the
samba-tool user syncpasswords command.
Default: unix password sync = no
use client driver (S)
This parameter applies only to Windows NT/2000 clients. It has no effect on Windows
95/98/ME clients. When serving a printer to Windows NT/2000 clients without first
installing a valid printer driver on the Samba host, the client will be required to
install a local printer driver. From this point on, the client will treat the print as
a local printer and not a network printer connection. This is much the same behavior
that will occur when disable spoolss = yes.
The differentiating factor is that under normal circumstances, the NT/2000 client will
attempt to open the network printer using MS-RPC. The problem is that because the
client considers the printer to be local, it will attempt to issue the OpenPrinterEx()
call requesting access rights associated with the logged on user. If the user
possesses local administrator rights but not root privilege on the Samba host (often
the case), the OpenPrinterEx() call will fail. The result is that the client will now
display an "Access Denied; Unable to connect" message in the printer queue window
(even though jobs may successfully be printed).
If this parameter is enabled for a printer, then any attempt to open the printer with
the PRINTER_ACCESS_ADMINISTER right is mapped to PRINTER_ACCESS_USE instead. Thus
allowing the OpenPrinterEx() call to succeed. This parameter MUST not be enabled on a
print share which has valid print driver installed on the Samba server.
Default: use client driver = no
use mmap (G)
This global parameter determines if the tdb internals of Samba can depend on mmap
working correctly on the running system. Samba requires a coherent mmap/read-write
system memory cache. Currently only OpenBSD and HPUX do not have such a coherent
cache, and on those platforms this parameter is overridden internally to be
effectively no. On all systems this parameter should be left alone. This parameter is
provided to help the Samba developers track down problems with the tdb internal code.
Default: use mmap = yes
username level (G)
This option helps Samba to try and 'guess' at the real UNIX username, as many DOS
clients send an all-uppercase username. By default Samba tries all lowercase, followed
by the username with the first letter capitalized, and fails if the username is not
found on the UNIX machine.
If this parameter is set to non-zero the behavior changes. This parameter is a number
that specifies the number of uppercase combinations to try while trying to determine
the UNIX user name. The higher the number the more combinations will be tried, but the
slower the discovery of usernames will be. Use this parameter when you have strange
usernames on your UNIX machine, such as AstrangeUser .
This parameter is needed only on UNIX systems that have case sensitive usernames.
Default: username level = 0
Example: username level = 5
username map (G)
This option allows you to specify a file containing a mapping of usernames from the
clients to the server. This can be used for several purposes. The most common is to
map usernames that users use on DOS or Windows machines to those that the UNIX box
uses. The other is to map multiple users to a single username so that they can more
easily share files.
Please note that for user mode security, the username map is applied prior to
validating the user credentials. Domain member servers (domain or ads) apply the
username map after the user has been successfully authenticated by the domain
controller and require fully qualified entries in the map table (e.g. biddle =
DOMAIN\foo).
The map file is parsed line by line. Each line should contain a single UNIX username
on the left then a '=' followed by a list of usernames on the right. The list of
usernames on the right may contain names of the form @group in which case they will
match any UNIX username in that group. The special client name '*' is a wildcard and
matches any name. Each line of the map file may be up to 1023 characters long.
The file is processed on each line by taking the supplied username and comparing it
with each username on the right hand side of the '=' signs. If the supplied name
matches any of the names on the right hand side then it is replaced with the name on
the left. Processing then continues with the next line.
If any line begins with a '#' or a ';' then it is ignored.
If any line begins with an '!' then the processing will stop after that line if a
mapping was done by the line. Otherwise mapping continues with every line being
processed. Using '!' is most useful when you have a wildcard mapping line later in the
file.
For example to map from the name admin or administrator to the UNIX name
root you would use:
root = admin administrator
Or to map anyone in the UNIX group system to the UNIX name sys you would use:
sys = @system
You can have as many mappings as you like in a username map file.
If your system supports the NIS NETGROUP option then the netgroup database is checked
before the /etc/group database for matching groups.
You can map Windows usernames that have spaces in them by using double quotes around
the name. For example:
tridge = "Andrew Tridgell"
would map the windows username "Andrew Tridgell" to the unix username "tridge".
The following example would map mary and fred to the unix user sys, and map the rest
to guest. Note the use of the '!' to tell Samba to stop processing if it gets a match
on that line:
!sys = mary fred
guest = *
Note that the remapping is applied to all occurrences of usernames. Thus if you
connect to \\server\fred and fred is remapped to mary then you will actually be
connecting to \\server\mary and will need to supply a password suitable for mary not
fred. The only exception to this is the username passed to a Domain Controller (if you
have one). The DC will receive whatever username the client supplies without
modification.
Also note that no reverse mapping is done. The main effect this has is with printing.
Users who have been mapped may have trouble deleting print jobs as PrintManager under
WfWg will think they don't own the print job.
Samba versions prior to 3.0.8 would only support reading the fully qualified username
(e.g.: DOMAIN\user) from the username map when performing a kerberos login from a
client. However, when looking up a map entry for a user authenticated by NTLM[SSP],
only the login name would be used for matches. This resulted in inconsistent behavior
sometimes even on the same server.
The following functionality is obeyed in version 3.0.8 and later:
When performing local authentication, the username map is applied to the login name
before attempting to authenticate the connection.
When relying upon a external domain controller for validating authentication requests,
smbd will apply the username map to the fully qualified username (i.e. DOMAIN\user)
only after the user has been successfully authenticated.
An example of use is:
username map = /usr/local/samba/lib/users.map
Default: username map = # no username map
username map cache time (G)
Mapping usernames with the username map or username map script features of Samba can
be relatively expensive. During login of a user, the mapping is done several times. In
particular, calling the username map script can slow down logins if external databases
have to be queried from the script being called.
The parameter username map cache time controls a mapping cache. It specifies the
number of seconds a mapping from the username map file or script is to be efficiently
cached. The default of 0 means no caching is done.
Default: username map cache time = 0
Example: username map cache time = 60
username map script (G)
This script is a mutually exclusive alternative to the username map parameter. This
parameter specifies an external program or script that must accept a single command
line option (the username transmitted in the authentication request) and return a line
on standard output (the name to which the account should mapped). In this way, it is
possible to store username map tables in an LDAP directory services.
Default: username map script =
Example: username map script = /etc/samba/scripts/mapusers.sh
usershare allow guests (G)
This parameter controls whether user defined shares are allowed to be accessed by
non-authenticated users or not. It is the equivalent of allowing people who can create
a share the option of setting guest ok = yes in a share definition. Due to its
security sensitive nature, the default is set to off.
Default: usershare allow guests = no
usershare max shares (G)
This parameter specifies the number of user defined shares that are allowed to be
created by users belonging to the group owning the usershare directory. If set to zero
(the default) user defined shares are ignored.
Default: usershare max shares = 100
usershare owner only (G)
This parameter controls whether the pathname exported by a user defined shares must be
owned by the user creating the user defined share or not. If set to True (the default)
then smbd checks that the directory path being shared is owned by the user who owns
the usershare file defining this share and refuses to create the share if not. If set
to False then no such check is performed and any directory path may be exported
regardless of who owns it.
Default: usershare owner only = yes
usershare path (G)
This parameter specifies the absolute path of the directory on the filesystem used to
store the user defined share definition files. This directory must be owned by root,
and have no access for other, and be writable only by the group owner. In addition the
"sticky" bit must also be set, restricting rename and delete to owners of a file (in
the same way the /tmp directory is usually configured). Members of the group owner of
this directory are the users allowed to create usershares.
For example, a valid usershare directory might be /usr/local/samba/lib/usershares, set
up as follows.
ls -ld /usr/local/samba/lib/usershares/
drwxrwx--T 2 root power_users 4096 2006-05-05 12:27 /usr/local/samba/lib/usershares/
In this case, only members of the group "power_users" can create user defined shares.
Default: usershare path = /var/lib/samba/usershares
usershare prefix allow list (G)
This parameter specifies a list of absolute pathnames the root of which are allowed to
be exported by user defined share definitions. If the pathname to be exported doesn't
start with one of the strings in this list, the user defined share will not be
allowed. This allows the Samba administrator to restrict the directories on the system
that can be exported by user defined shares.
If there is a "usershare prefix deny list" and also a "usershare prefix allow list"
the deny list is processed first, followed by the allow list, thus leading to the most
restrictive interpretation.
Default: usershare prefix allow list =
Example: usershare prefix allow list = /home /data /space
usershare prefix deny list (G)
This parameter specifies a list of absolute pathnames the root of which are NOT
allowed to be exported by user defined share definitions. If the pathname exported
starts with one of the strings in this list the user defined share will not be
allowed. Any pathname not starting with one of these strings will be allowed to be
exported as a usershare. This allows the Samba administrator to restrict the
directories on the system that can be exported by user defined shares.
If there is a "usershare prefix deny list" and also a "usershare prefix allow list"
the deny list is processed first, followed by the allow list, thus leading to the most
restrictive interpretation.
Default: usershare prefix deny list =
Example: usershare prefix deny list = /etc /dev /private
usershare template share (G)
User defined shares only have limited possible parameters such as path, guest ok, etc.
This parameter allows usershares to "cloned" from an existing share. If "usershare
template share" is set to the name of an existing share, then all usershares created
have their defaults set from the parameters set on this share.
The target share may be set to be invalid for real file sharing by setting the
parameter "-valid = False" on the template share definition. This causes it not to be
seen as a real exported share but to be able to be used as a template for usershares.
Default: usershare template share =
Example: usershare template share = template_share
use sendfile (S)
If this parameter is yes, and the sendfile() system call is supported by the
underlying operating system, then some SMB read calls (mainly ReadAndX and ReadRaw)
will use the more efficient sendfile system call for files that are exclusively
oplocked. This may make more efficient use of the system CPU's and cause Samba to be
faster. Samba automatically turns this off for clients that use protocol levels lower
than NT LM 0.12 and when it detects a client is Windows 9x (using sendfile from Linux
will cause these clients to fail).
Default: use sendfile = no
utmp (G)
This boolean parameter is only available if Samba has been configured and compiled
with the option --with-utmp. If set to yes then Samba will attempt to add utmp or
utmpx records (depending on the UNIX system) whenever a connection is made to a Samba
server. Sites may use this to record the user connecting to a Samba share.
Due to the requirements of the utmp record, we are required to create a unique
identifier for the incoming user. Enabling this option creates an n^2 algorithm to
find this number. This may impede performance on large installations.
Default: utmp = no
utmp directory (G)
This parameter is only available if Samba has been configured and compiled with the
option --with-utmp. It specifies a directory pathname that is used to store the utmp
or utmpx files (depending on the UNIX system) that record user connections to a Samba
server. By default this is not set, meaning the system will use whatever utmp file the
native system is set to use (usually /var/run/utmp on Linux).
Default: utmp directory = # Determined automatically
Example: utmp directory = /var/run/utmp
-valid (S)
This parameter indicates whether a share is valid and thus can be used. When this
parameter is set to false, the share will be in no way visible nor accessible.
This option should not be used by regular users but might be of help to developers.
Samba uses this option internally to mark shares as deleted.
Default: -valid = yes
valid users (S)
This is a list of users that should be allowed to login to this service. Names
starting with '@', '+' and '&' are interpreted using the same rules as described in
the invalid users parameter.
If this is empty (the default) then any user can login. If a username is in both this
list and the invalid users list then access is denied for that user.
The current servicename is substituted for %S. This is useful in the [homes] section.
Note: When used in the [global] section this parameter may have unwanted side effects.
For example: If samba is configured as a MASTER BROWSER (see local master, os level,
domain master, preferred master) this option will prevent workstations from being able
to browse the network.
Default: valid users = # No valid users list (anyone can login)
Example: valid users = greg, @pcusers
veto files (S)
This is a list of files and directories that are neither visible nor accessible. Each
entry in the list must be separated by a '/', which allows spaces to be included in
the entry. '*' and '?' can be used to specify multiple files or directories as in DOS
wildcards.
Each entry must be a unix path, not a DOS path and must not include the unix directory
separator '/'.
Note that the case sensitive option is applicable in vetoing files.
One feature of the veto files parameter that it is important to be aware of is Samba's
behaviour when trying to delete a directory. If a directory that is to be deleted
contains nothing but veto files this deletion will fail unless you also set the delete
veto files parameter to yes.
Setting this parameter will affect the performance of Samba, as it will be forced to
check all files and directories for a match as they are scanned.
Examples of use include:
; Veto any files containing the word Security,
; any ending in .tmp, and any directory containing the
; word root.
veto files = /*Security*/*.tmp/*root*/
; Veto the Apple specific files that a NetAtalk server
; creates.
veto files = /.AppleDouble/.bin/.AppleDesktop/Network Trash Folder/
Default: veto files = # No files or directories are vetoed
veto oplock files (S)
This parameter is only valid when the oplocks parameter is turned on for a share. It
allows the Samba administrator to selectively turn off the granting of oplocks on
selected files that match a wildcarded list, similar to the wildcarded list used in
the veto files parameter.
You might want to do this on files that you know will be heavily contended for by
clients. A good example of this is in the NetBench SMB benchmark program, which causes
heavy client contention for files ending in .SEM. To cause Samba not to grant oplocks
on these files you would use the line (either in the [global] section or in the
section for the particular NetBench share.
An example of use is:
veto oplock files = /.*SEM/
Default: veto oplock files = # No files are vetoed for oplock grants
vfs object
This parameter is a synonym for vfs objects.
vfs objects (S)
This parameter specifies the backend names which are used for Samba VFS I/O
operations. By default, normal disk I/O operations are used but these can be
overloaded with one or more VFS objects. Be aware that the definition of this
parameter will overwrite a possible previous definition of the vfs objects parameter.
Default: vfs objects =
Example: vfs objects = extd_audit recycle
volume (S)
This allows you to override the volume label returned for a share. Useful for CDROMs
with installation programs that insist on a particular volume label.
Default: volume = # the name of the share
volume serial number (S)
This allows to override the volume serial number (a 32bit value) reported for a share.
The special value -1 (default) stands for a unique number that is calculated for each
share.
Default: volume serial number = -1
Example: volume serial number = 0xabcdefgh
wide links (S)
This parameter controls whether or not links in the UNIX file system may be followed
by the server. Links that point to areas within the directory tree exported by the
server are always allowed; this parameter controls access only to areas that are
outside the directory tree being exported.
Note: Turning this parameter on when UNIX extensions are enabled will allow UNIX
clients to create symbolic links on the share that can point to files or directories
outside restricted path exported by the share definition. This can cause access to
areas outside of the share. Due to this problem, this parameter will be automatically
disabled (with a message in the log file) if the unix extensions option is on.
See the parameter allow insecure wide links if you wish to change this coupling
between the two parameters.
Default: wide links = no
winbind cache time (G)
This parameter specifies the number of seconds the winbindd(8) daemon will cache user
and group information before querying a Windows NT server again.
This does not apply to authentication requests, these are always evaluated in real
time unless the winbind offline logon option has been enabled.
Default: winbind cache time = 300
winbindd socket directory (G)
This setting controls the location of the winbind daemon's socket.
Except within automated test scripts, this should not be altered, as the client tools
(nss_winbind etc) do not honour this parameter. Client tools must then be advised of
the altered path with the WINBINDD_SOCKET_DIR environment variable.
Default: winbindd socket directory = /run/samba/winbindd
winbind enum groups (G)
On large installations using winbindd(8) it may be necessary to suppress the
enumeration of groups through the setgrent(), getgrent() and endgrent() group of
system calls. If the winbind enum groups parameter is no, calls to the getgrent()
system call will not return any data.
Warning
Turning off group enumeration may cause some programs to behave oddly.
Default: winbind enum groups = no
winbind enum users (G)
On large installations using winbindd(8) it may be necessary to suppress the
enumeration of users through the setpwent(), getpwent() and endpwent() group of system
calls. If the winbind enum users parameter is no, calls to the getpwent system call
will not return any data.
Warning
Turning off user enumeration may cause some programs to behave oddly. For example,
the finger program relies on having access to the full user list when searching
for matching usernames.
Default: winbind enum users = no
winbind expand groups (G)
This option controls the maximum depth that winbindd will traverse when flattening
nested group memberships of Windows domain groups. This is different from the winbind
nested groups option which implements the Windows NT4 model of local group nesting.
The "winbind expand groups" parameter specifically applies to the membership of domain
groups.
This option also affects the return of non nested group memberships of Windows domain
users. With the new default "winbind expand groups = 0" winbind does not query group
memberships at all.
Be aware that a high value for this parameter can result in system slowdown as the
main parent winbindd daemon must perform the group unrolling and will be unable to
answer incoming NSS or authentication requests during this time.
The default value was changed from 1 to 0 with Samba 4.2. Some broken applications
(including some implementations of newgrp and sg) calculate the group memberships of
users by traversing groups, such applications will require "winbind expand groups =
1". But the new default makes winbindd more reliable as it doesn't require SAMR access
to domain controllers of trusted domains.
Default: winbind expand groups = 0
winbind:ignore domains (G)
Allows one to enter a list of trusted domains winbind should ignore (untrust). This
can avoid the overhead of resources from attempting to login to DCs that should not be
communicated with.
Default: winbind:ignore domains =
Example: winbind:ignore domains = DOMAIN1, DOMAIN2
winbind max clients (G)
This parameter specifies the maximum number of clients the winbindd(8) daemon can
connect with. The parameter is not a hard limit. The winbindd(8) daemon configures
itself to be able to accept at least that many connections, and if the limit is
reached, an attempt is made to disconnect idle clients.
Default: winbind max clients = 200
winbind max domain connections (G)
This parameter specifies the maximum number of simultaneous connections that the
winbindd(8) daemon should open to the domain controller of one domain. Setting this
parameter to a value greater than 1 can improve scalability with many simultaneous
winbind requests, some of which might be slow. Changing this value requires a restart
of winbindd.
Note that if winbind offline logon is set to Yes, then only one DC connection is
allowed per domain, regardless of this setting.
Default: winbind max domain connections = 1
Example: winbind max domain connections = 10
winbind nested groups (G)
If set to yes, this parameter activates the support for nested groups. Nested groups
are also called local groups or aliases. They work like their counterparts in Windows:
Nested groups are defined locally on any machine (they are shared between DC's through
their SAM) and can contain users and global groups from any trusted SAM. To be able to
use nested groups, you need to run nss_winbind.
Default: winbind nested groups = yes
winbind normalize names (G)
This parameter controls whether winbindd will replace whitespace in user and group
names with an underscore (_) character. For example, whether the name "Space Kadet"
should be replaced with the string "space_kadet". Frequently Unix shell scripts will
have difficulty with usernames contains whitespace due to the default field separator
in the shell. If your domain possesses names containing the underscore character, this
option may cause problems unless the name aliasing feature is supported by your
nss_info plugin.
This feature also enables the name aliasing API which can be used to make domain user
and group names to a non-qualified version. Please refer to the manpage for the
configured idmap and nss_info plugin for the specifics on how to configure name
aliasing for a specific configuration. Name aliasing takes precedence (and is mutually
exclusive) over the whitespace replacement mechanism discussed previously.
Default: winbind normalize names = no
Example: winbind normalize names = yes
winbind nss info (G)
This parameter is designed to control how Winbind retrieves Name Service Information
to construct a user's home directory and login shell. Currently the following settings
are available:
• template - The default, using the parameters of template shell and template
homedir)
• <sfu | sfu20 | rfc2307 > - When Samba is running in security = ads and your
Active Directory Domain Controller does support the Microsoft "Services for
Unix" (SFU) LDAP schema, winbind can retrieve the login shell and the home
directory attributes directly from your Directory Server. For SFU 3.0 or
3.5 simply choose "sfu", if you use SFU 2.0 please choose "sfu20".
Note that for the idmap backend idmap_ad you need to configure those
settings in the idmap configuration section. Make sure to consult the
documentation of the idmap backend that you are using.
Default: winbind nss info = template
Example: winbind nss info = sfu
winbind offline logon (G)
This parameter is designed to control whether Winbind should allow one to login with
the pam_winbind module using Cached Credentials. If enabled, winbindd will store user
credentials from successful logins encrypted in a local cache.
Default: winbind offline logon = no
Example: winbind offline logon = yes
winbind reconnect delay (G)
This parameter specifies the number of seconds the winbindd(8) daemon will wait
between attempts to contact a Domain controller for a domain that is determined to be
down or not contactable.
Default: winbind reconnect delay = 30
winbind refresh tickets (G)
This parameter is designed to control whether Winbind should refresh Kerberos Tickets
retrieved using the pam_winbind module.
Default: winbind refresh tickets = no
Example: winbind refresh tickets = yes
winbind request timeout (G)
This parameter specifies the number of seconds the winbindd(8) daemon will wait before
disconnecting either a client connection with no outstanding requests (idle) or a
client connection with a request that has remained outstanding (hung) for longer than
this number of seconds.
Default: winbind request timeout = 60
winbind rpc only (G)
Setting this parameter to yes forces winbindd to use RPC instead of LDAP to retrieve
information from Domain Controllers.
Default: winbind rpc only = no
winbind scan trusted domains (G)
This option only takes effect when the security option is set to domain or ads. If it
is set to yes, winbindd periodically tries to scan for new trusted domains and adds
them to a global list inside of winbindd. The list can be extracted with wbinfo
--trusted-domains --verbose. Setting it to yes matches the behaviour of Samba 4.7 and
older.
The construction of that global list is not reliable and often incomplete in complex
trust setups. In most situations the list is not needed any more for winbindd to
operate correctly. E.g. for plain file serving via SMB using a simple idmap setup with
autorid, tdb or ad. However some more complex setups require the list, e.g. if you
specify idmap backends for specific domains. Some pam_winbind setups may also require
the global list.
If you have a setup that doesn't require the global list, you should set winbind scan
trusted domains = no.
Default: winbind scan trusted domains = no
winbind sealed pipes (G)
This option controls whether any requests from winbindd to domain controllers pipe
will be sealed. Disabling sealing can be useful for debugging purposes.
The behavior can be controlled per netbios domain by using 'winbind sealed
pipes:NETBIOSDOMAIN = no' as option.
Default: winbind sealed pipes = yes
winbind separator (G)
This parameter allows an admin to define the character used when listing a username of
the form of DOMAIN \user. This parameter is only applicable when using the
pam_winbind.so and nss_winbind.so modules for UNIX services.
Please note that setting this parameter to + causes problems with group membership at
least on glibc systems, as the character + is used as a special character for NIS in
/etc/group.
Default: winbind separator = \
Example: winbind separator = +
winbind use default domain (G)
This parameter specifies whether the winbindd(8) daemon should operate on users
without domain component in their username. Users without a domain component are
treated as is part of the winbindd server's own domain. While this does not benefit
Windows users, it makes SSH, FTP and e-mail function in a way much closer to the way
they would in a native unix system.
This option should be avoided if possible. It can cause confusion about
responsibilities for a user or group. In many situations it is not clear whether
winbind or /etc/passwd should be seen as authoritative for a user, likewise for
groups.
Default: winbind use default domain = no
Example: winbind use default domain = yes
winbind use krb5 enterprise principals (G)
winbindd is able to get kerberos tickets for pam_winbind with krb5_auth or wbinfo
-K/--krb5auth=.
winbindd (at least on a domain member) is never be able to have a complete picture of
the trust topology (which is managed by the DCs). There might be uPNSuffixes and
msDS-SPNSuffixes values, which don't belong to any AD domain at all.
With winbind scan trusted domains = no winbindd doesn't even get a complete picture of
the topology.
It is not really required to know about the trust topology. We can just rely on the
[K]DCs of our primary domain (e.g. PRIMARY.A.EXAMPLE.COM) and use enterprise
principals e.g. upnfromB@B.EXAMPLE.COM@PRIMARY.A.EXAMPLE.COM and follow the
WRONG_REALM referrals in order to find the correct DC. The final principal might be
userfromB@INTERNALB.EXAMPLE.PRIVATE.
With winbind use krb5 enterprise principals = yes winbindd enterprise principals will
be used.
Default: winbind use krb5 enterprise principals = yes
Example: winbind use krb5 enterprise principals = no
winsdb:local_owner (G)
This specifies the address that is stored in the winsOwner attribute, of locally
registered winsRecord-objects. The default is to use the ip-address of the first
network interface.
No default
winsdb:dbnosync (G)
This parameter disables fsync() after changes of the WINS database.
Default: winsdb:dbnosync = no
wins hook (G)
When Samba is running as a WINS server this allows you to call an external program for
all changes to the WINS database. The primary use for this option is to allow the
dynamic update of external name resolution databases such as dynamic DNS.
The wins hook parameter specifies the name of a script or executable that will be
called as follows:
wins_hook operation name nametype ttl IP_list
• The first argument is the operation and is one of "add", "delete", or
"refresh". In most cases the operation can be ignored as the rest of the
parameters provide sufficient information. Note that "refresh" may
sometimes be called when the name has not previously been added, in that
case it should be treated as an add.
• The second argument is the NetBIOS name. If the name is not a legal name
then the wins hook is not called. Legal names contain only letters, digits,
hyphens, underscores and periods.
• The third argument is the NetBIOS name type as a 2 digit hexadecimal
number.
• The fourth argument is the TTL (time to live) for the name in seconds.
• The fifth and subsequent arguments are the IP addresses currently
registered for that name. If this list is empty then the name should be
deleted.
An example script that calls the BIND dynamic DNS update program nsupdate is provided
in the examples directory of the Samba source code.
No default
wins proxy (G)
This is a boolean that controls if nmbd(8) will respond to broadcast name queries on
behalf of other hosts. You may need to set this to yes for some older clients.
Default: wins proxy = no
wins server (G)
This specifies the IP address (or DNS name: IP address for preference) of the WINS
server that nmbd(8) should register with. If you have a WINS server on your network
then you should set this to the WINS server's IP.
You should point this at your WINS server if you have a multi-subnetted network.
If you want to work in multiple namespaces, you can give every wins server a 'tag'.
For each tag, only one (working) server will be queried for a name. The tag should be
separated from the ip address by a colon.
Note
You need to set up Samba to point to a WINS server if you have multiple subnets
and wish cross-subnet browsing to work correctly.
See the chapter in the Samba3-HOWTO on Network Browsing.
Default: wins server =
Example: wins server = mary:192.9.200.1 fred:192.168.3.199 mary:192.168.2.61 # For
this example when querying a certain name, 192.19.200.1 will be asked first and if
that doesn't respond 192.168.2.61. If either of those doesn't know the name
192.168.3.199 will be queried.
Example: wins server = 192.9.200.1 192.168.2.61
wins support (G)
This boolean controls if the nmbd(8) process in Samba will act as a WINS server. You
should not set this to yes unless you have a multi-subnetted network and you wish a
particular nmbd to be your WINS server. Note that you should NEVER set this to yes on
more than one machine in your network.
Default: wins support = no
workgroup (G)
This controls what workgroup your server will appear to be in when queried by clients.
Note that this parameter also controls the Domain name used with the security = domain
setting.
Default: workgroup = WORKGROUP
Example: workgroup = MYGROUP
wreplsrv:periodic_interval (G)
This maximum interval in seconds between 2 periodically scheduled runs where we check
for wins.ldb changes and do push notifications to our push partners. Also
wins_config.ldb changes are checked in that interval and partner configuration reloads
are done.
Default: wreplsrv:periodic_interval = 15
wreplsrv:propagate name releases (G)
If this parameter is enabled, then explicit (from the client) and implicit (via the
scavenging) name releases are propagated to the other servers directly, even if there
are still other addresses active, this applies to SPECIAL GROUP (2) and MULTIHOMED (3)
entries. Also the replication conflict merge algorithm for SPECIAL GROUP (2) entries
discards replica addresses where the address owner is the local server, if the address
was not stored locally before. The merge result is propagated directly in case an
address was discarded. A Windows servers doesn't propagate name releases of SPECIAL
GROUP (2) and MULTIHOMED (3) entries directly, which means that Windows servers may
return different results to name queries for SPECIAL GROUP (2) and MULTIHOMED (3)
names. The option doesn't have much negative impact if Windows servers are around, but
be aware that they might return unexpected results.
Default: wreplsrv:propagate name releases = no
wreplsrv:scavenging_interval (G)
This is the interval in s between 2 scavenging runs which clean up the WINS database
and changes the states of expired name records. Defaults to half of the value of
wreplsrv:renew_interval.
No default
wreplsrv:tombstone_extra_timeout (G)
This is the time in s the server needs to be up till we'll remove tombstone records
from our database. Defaults to 3 days.
Default: wreplsrv:tombstone_extra_timeout = 259200
wreplsrv:tombstone_interval (G)
This is the interval in s till released records of the WINS server become tombstone.
Defaults to 6 days.
Default: wreplsrv:tombstone_interval = 518400
wreplsrv:tombstone_timeout (G)
This is the interval in s till tombstone records are deleted from the WINS database.
Defaults to 1 day.
Default: wreplsrv:tombstone_timeout = 86400
wreplsrv:verify_interval (G)
This is the interval in s till we verify active replica records with the owning WINS
server. Unfortunately not implemented yet. Defaults to 24 days.
Default: wreplsrv:verify_interval = 2073600
writable
This parameter is a synonym for writeable.
write ok
This parameter is a synonym for writeable.
writeable (S)
Inverted synonym for read only.
Default: writeable = no
write list (S)
This is a list of users that are given read-write access to a service. If the
connecting user is in this list then they will be given write access, no matter what
the read only option is set to. The list can include group names using the @group
syntax.
Note that if a user is in both the read list and the write list then they will be
given write access.
Default: write list =
Example: write list = admin, root, @staff
write raw (G)
This is ignored if async smb echo handler is set, because this feature is incompatible
with raw write SMB requests
If enabled, raw writes allow writes of 65535 bytes in one packet. This typically
provides a major performance benefit for some very, very old clients.
However, some clients either negotiate the allowable block size incorrectly or are
incapable of supporting larger block sizes, and for these clients you may need to
disable raw writes.
In general this parameter should be viewed as a system tuning tool and left severely
alone.
Default: write raw = yes
wsp property file (G)
wsp property file parameter. This parameter specifies the file where additional WSP
Windows Search Protocol properties are stored. The format of the file is a csv
consisting of 10 comma separated columns. The first 3 columns are required, the other
columns are desirable but not necessary.
Property Name
A property name e.g. System.ItemUrl.
GUID
A guid that identifies the propertyset the property belongs to.
prop ID
A number that together with the GUID uniquely identifies the property.
inInverted Index
Set to TRUE is the property is indexed.
isColumn
Set to TRUE if the property is one that can be returned in rows returned from WSP
query.
type
One of Boolean,Buffer,Byte,DateTime,Double,Int32,String,UInt16,UInt32,UInt64
MaxSize
maximum size when stored.
Vector Property
TRUE if this is a multivalue property.
Description
Description of what the property is used for.
Default: wsp property file =
wtmp directory (G)
This parameter is only available if Samba has been configured and compiled with the
option --with-utmp. It specifies a directory pathname that is used to store the wtmp
or wtmpx files (depending on the UNIX system) that record user connections to a Samba
server. The difference with the utmp directory is the fact that user info is kept
after a user has logged out.
By default this is not set, meaning the system will use whatever utmp file the native
system is set to use (usually /var/run/wtmp on Linux).
Default: wtmp directory =
Example: wtmp directory = /var/log/wtmp
WARNINGS
Although the configuration file permits service names to contain spaces, your client
software may not. Spaces will be ignored in comparisons anyway, so it shouldn't be a
problem - but be aware of the possibility.
On a similar note, many clients - especially DOS clients - limit service names to eight
characters. smbd(8) has no such limitation, but attempts to connect from such clients
will fail if they truncate the service names. For this reason you should probably keep
your service names down to eight characters in length.
Use of the [homes] and [printers] special sections make life for an administrator easy,
but the various combinations of default attributes can be tricky. Take extreme care when
designing these sections. In particular, ensure that the permissions on spool directories
are correct.
VERSION
This man page is part of version 4.20.4-Ubuntu-4.20.4+dfsg-1ubuntu1 of the Samba suite.
SEE ALSO
samba(7), smbpasswd(8), smbd(8), nmbd(8), winbindd(8), samba(8), samba-tool(8),
smbclient(1), nmblookup(1), testparm(1).
AUTHOR
The original Samba software and related utilities were created by Andrew Tridgell. Samba
is now developed by the Samba Team as an Open Source project similar to the way the Linux
kernel is developed.