Provided by: winbind_3.6.3-2ubuntu2_amd64 bug

NAME

       winbindd - Name Service Switch daemon for resolving names from NT servers

SYNOPSIS

       winbindd [-D] [-F] [-S] [-i] [-Y] [-d <debug level>] [-s <smb config file>] [-n]

DESCRIPTION

       This program is part of the samba(7) suite.

       winbindd is a daemon that provides a number of services to the Name Service Switch
       capability found in most modern C libraries, to arbitrary applications via PAM and
       ntlm_auth and to Samba itself.

       Even if winbind is not used for nsswitch, it still provides a service to smbd, ntlm_auth
       and the pam_winbind.so PAM module, by managing connections to domain controllers. In this
       configuration the idmap config * : range parameter is not required. (This is known as
       `netlogon proxy only mode´.)

       The Name Service Switch allows user and system information to be obtained from different
       databases services such as NIS or DNS. The exact behaviour can be configured through the
       /etc/nsswitch.conf file. Users and groups are allocated as they are resolved to a range of
       user and group ids specified by the administrator of the Samba system.

       The service provided by winbindd is called `winbind´ and can be used to resolve user and
       group information from a Windows NT server. The service can also provide authentication
       services via an associated PAM module.

       The pam_winbind module supports the auth, account and password module-types. It should be
       noted that the account module simply performs a getpwnam() to verify that the system can
       obtain a uid for the user, as the domain controller has already performed access control.
       If the libnss_winbind library has been correctly installed, or an alternate source of
       names configured, this should always succeed.

       The following nsswitch databases are implemented by the winbindd service:

       hosts
           This feature is only available on IRIX. User information traditionally stored in the
           hosts(5) file and used by gethostbyname(3) functions. Names are resolved through the
           WINS server or by broadcast.

       passwd
           User information traditionally stored in the passwd(5) file and used by getpwent(3)
           functions.

       group
           Group information traditionally stored in the group(5) file and used by getgrent(3)
           functions.

       For example, the following simple configuration in the /etc/nsswitch.conf file can be used
       to initially resolve user and group information from /etc/passwd and /etc/group and then
       from the Windows NT server.

           passwd:         files winbind
           group:          files winbind
           ## only available on IRIX: use winbind to resolve hosts:
           # hosts:        files dns winbind
           ## All other NSS enabled systems should use libnss_wins.so like this:
           hosts:          files dns wins

       The following simple configuration in the /etc/nsswitch.conf file can be used to initially
       resolve hostnames from /etc/hosts and then from the WINS server.

           hosts:         files wins

OPTIONS

       -D
           If specified, this parameter causes the server to operate as a daemon. That is, it
           detaches itself and runs in the background on the appropriate port. This switch is
           assumed if winbindd is executed on the command line of a shell.

       -F
           If specified, this parameter causes the main winbindd process to not daemonize, i.e.
           double-fork and disassociate with the terminal. Child processes are still created as
           normal to service each connection request, but the main process does not exit. This
           operation mode is suitable for running winbindd under process supervisors such as
           supervise and svscan from Daniel J. Bernstein´s daemontools package, or the AIX
           process monitor.

       -S
           If specified, this parameter causes winbindd to log to standard output rather than a
           file.

       -d|--debuglevel=level
           level is an integer from 0 to 10. The default value if this parameter is not specified
           is 0.

           The higher this value, the more detail will be logged to the log files about the
           activities of the server. At level 0, only critical errors and serious warnings will
           be logged. Level 1 is a reasonable level for day-to-day running - it generates a small
           amount of information about operations carried out.

           Levels above 1 will generate considerable amounts of log data, and should only be used
           when investigating a problem. Levels above 3 are designed for use only by developers
           and generate HUGE amounts of log data, most of which is extremely cryptic.

           Note that specifying this parameter here will override the smb.conf.5.html# parameter
           in the smb.conf file.

       -V|--version
           Prints the program version number.

       -s|--configfile <configuration file>
           The file specified contains the configuration details required by the server. The
           information in this file includes server-specific information such as what printcap
           file to use, as well as descriptions of all the services that the server is to
           provide. See smb.conf for more information. The default configuration file name is
           determined at compile time.

       -l|--log-basename=logdirectory
           Base directory name for log/debug files. The extension ".progname" will be appended
           (e.g. log.smbclient, log.smbd, etc...). The log file is never removed by the client.

       -h|--help
           Print a summary of command line options.

       -i
           Tells winbindd to not become a daemon and detach from the current terminal. This
           option is used by developers when interactive debugging of winbindd is required.
           winbindd also logs to standard output, as if the -S parameter had been given.

       -n
           Disable caching. This means winbindd will always have to wait for a response from the
           domain controller before it can respond to a client and this thus makes things slower.
           The results will however be more accurate, since results from the cache might not be
           up-to-date. This might also temporarily hang winbindd if the DC doesn´t respond.

       -Y
           Single daemon mode. This means winbindd will run as a single process (the mode of
           operation in Samba 2.2). Winbindd´s default behavior is to launch a child process that
           is responsible for updating expired cache entries.

NAME AND ID RESOLUTION

       Users and groups on a Windows NT server are assigned a security id (SID) which is globally
       unique when the user or group is created. To convert the Windows NT user or group into a
       unix user or group, a mapping between SIDs and unix user and group ids is required. This
       is one of the jobs that winbindd performs.

       As winbindd users and groups are resolved from a server, user and group ids are allocated
       from a specified range. This is done on a first come, first served basis, although all
       existing users and groups will be mapped as soon as a client performs a user or group
       enumeration command. The allocated unix ids are stored in a database and will be
       remembered.

       WARNING: The SID to unix id database is the only location where the user and group
       mappings are stored by winbindd. If this store is deleted or corrupted, there is no way
       for winbindd to determine which user and group ids correspond to Windows NT user and group
       rids.

CONFIGURATION

       Configuration of the winbindd daemon is done through configuration parameters in the
       smb.conf(5) file. All parameters should be specified in the [global] section of smb.conf.

       ·    winbind separator

       ·    idmap config * : range

       ·    idmap config * : backend

       ·    winbind cache time

       ·    winbind enum users

       ·    winbind enum groups

       ·    template homedir

       ·    template shell

       ·    winbind use default domain

       ·    winbind: rpc only Setting this parameter forces winbindd to use RPC instead of LDAP
           to retrieve information from Domain Controllers.

EXAMPLE SETUP

       To setup winbindd for user and group lookups plus authentication from a domain controller
       use something like the following setup. This was tested on an early Red Hat Linux box.

       In /etc/nsswitch.conf put the following:

           passwd: files winbind
           group:  files winbind

       In /etc/pam.d/* replace the
        auth lines with something like this:

           auth  required    /lib/security/pam_securetty.so
           auth  required   /lib/security/pam_nologin.so
           auth  sufficient  /lib/security/pam_winbind.so
           auth  required    /lib/security/pam_unix.so \
                             use_first_pass shadow nullok

           Note
           The PAM module pam_unix has recently replaced the module pam_pwdb. Some Linux systems
           use the module pam_unix2 in place of pam_unix.

       Note in particular the use of the sufficient keyword and the use_first_pass keyword.

       Now replace the account lines with this:

       account required /lib/security/pam_winbind.so

       The next step is to join the domain. To do that use the net program like this:

       net join -S PDC -U Administrator

       The username after the -U can be any Domain user that has administrator privileges on the
       machine. Substitute the name or IP of your PDC for "PDC".

       Next copy libnss_winbind.so to /lib and pam_winbind.so to /lib/security. A symbolic link
       needs to be made from /lib/libnss_winbind.so to /lib/libnss_winbind.so.2. If you are using
       an older version of glibc then the target of the link should be /lib/libnss_winbind.so.1.

       Finally, setup a smb.conf(5) containing directives like the following:

           [global]
                winbind separator = +
                   winbind cache time = 10
                   template shell = /bin/bash
                   template homedir = /home/%D/%U
                   idmap config * : range = 10000-20000
                   workgroup = DOMAIN
                   security = domain
                   password server = *

       Now start winbindd and you should find that your user and group database is expanded to
       include your NT users and groups, and that you can login to your unix box as a domain
       user, using the DOMAIN+user syntax for the username. You may wish to use the commands
       getent passwd and getent group to confirm the correct operation of winbindd.

NOTES

       The following notes are useful when configuring and running winbindd:

       nmbd(8) must be running on the local machine for winbindd to work.

       PAM is really easy to misconfigure. Make sure you know what you are doing when modifying
       PAM configuration files. It is possible to set up PAM such that you can no longer log into
       your system.

       If more than one UNIX machine is running winbindd, then in general the user and groups ids
       allocated by winbindd will not be the same. The user and group ids will only be valid for
       the local machine, unless a shared idmap config * : backend is configured.

       If the the Windows NT SID to UNIX user and group id mapping file is damaged or destroyed
       then the mappings will be lost.

SIGNALS

       The following signals can be used to manipulate the winbindd daemon.

       SIGHUP
           Reload the smb.conf(5) file and apply any parameter changes to the running version of
           winbindd. This signal also clears any cached user and group information. The list of
           other domains trusted by winbindd is also reloaded.

       SIGUSR2
           The SIGUSR2 signal will cause winbindd to write status information to the winbind log
           file.

           Log files are stored in the filename specified by the log file parameter.

FILES

       /etc/nsswitch.conf(5)
           Name service switch configuration file.

       /tmp/.winbindd/pipe
           The UNIX pipe over which clients communicate with the winbindd program. For security
           reasons, the winbind client will only attempt to connect to the winbindd daemon if
           both the /tmp/.winbindd directory and /tmp/.winbindd/pipe file are owned by root.

       /var/run/samba/winbindd_privileged/pipe
           The UNIX pipe over which ´privileged´ clients communicate with the winbindd program.
           For security reasons, access to some winbindd functions - like those needed by the
           ntlm_auth utility - is restricted. By default, only users in the ´root´ group will get
           this access, however the administrator may change the group permissions on
           /var/run/samba/winbindd_privileged to allow programs like ´squid´ to use ntlm_auth.
           Note that the winbind client will only attempt to connect to the winbindd daemon if
           both the /var/run/samba/winbindd_privileged directory and
           /var/run/samba/winbindd_privileged/pipe file are owned by root.

       /lib/libnss_winbind.so.X
           Implementation of name service switch library.

       /var/run/samba/winbindd_idmap.tdb
           Storage for the Windows NT rid to UNIX user/group id mapping.

       /var/run/samba/winbindd_cache.tdb
           Storage for cached user and group information.

VERSION

       This man page is correct for version 3 of the Samba suite.

SEE ALSO

       nsswitch.conf(5), samba(7), wbinfo(1), ntlm_auth(8), smb.conf(5), pam_winbind(8)

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.

       wbinfo and winbindd were written by Tim Potter.

       The conversion to DocBook for Samba 2.2 was done by Gerald Carter. The conversion to
       DocBook XML 4.2 for Samba 3.0 was done by Alexander Bokovoy.