Provided by: autofs_5.1.1-1ubuntu3.1_amd64 
NAME
auto.master - Master Map for automounter
DESCRIPTION
The auto.master map is consulted to set up automount managed mount points when the autofs(8) script is
invoked or the automount(8) program is run. Each line describes a mount point and refers to an autofs map
describing file systems to be mounted under the mount point.
The default location of the master map is /etc/auto.master but an alternate name may be given on the
command line when running the automounter and the default master map may changed by setting the
MASTER_MAP_NAME configuration variable in /etc/default/autofs. If the master map name has no path then
the system Name Service Switch configuration will be consulted and each of the sources searched in line
with the rules given in the Name Service Switch configuration.
Access to mounts in maps is governed by a key.
For direct maps the mount point is always specified as:
/-
and the key used within the direct map is the full path to the mount point. The direct map may have
multiple entries in the master map.
For indirect maps access is by using the path scheme:
/mount-point/key
where mount-point is one of the entries listed in the master map. The key is a single directory component
and is matched against entries in the map given in the entry (See autofs(5)).
Additionally, a map may be included from its source as if it were itself present in the master map by
including a line of the form:
+[maptype[,format]:]map [options]
and automount(8) will process the map according to the specification described below for map entries.
Indirect map entries must be unique in the master map so second and subsequent entries for an indirect
mount point are ignored by automount(8).
FORMAT
Master map entries have three fields separated by an arbitrary number of spaces or tabs. Lines beginning
with # are comments. The first field is the mount point described above and the second field is the name
of the map to be consulted for the mount point followed by the third field which contains options to be
applied to all entries in the map.
The format of a master map entry is:
mount-point [map-type[,format]:]map [options]
mount-point
Base location for the autofs filesystem to be mounted. For indirect maps this directory will be
created (as with mkdir -p) and is removed when the autofs filesystem is umounted.
map-type
Type of map used for this mount point. The following are valid map types:
file The map is a regular text file.
program
The map is an executable program, which is passed a key on the command line and returns an
entry (everything besides the key) on stdout if successful. Optinally, the keyword exec
may be used as a synonym for program to avoid confusion with amd formated maps mount type
program.
yp The map is a NIS (YP) database.
nisplus
The map is a NIS+ database.
hesiod The map is a hesiod database whose filsys entries are used for maps.
ldap or ldaps
The map is stored in an LDAP directory. If ldaps is used the appropriate certificate must
be configured in the LDAP client.
multi This map type allows the specification of multiple maps separated by "--". These maps are
searched in order to resolve key lookups.
dir This map type can be used at + master map including notation. The contents of files under
given directory are included to the master map. The name of file to be included must be
ended with ".autofs". A file will be ignored if its name is not ended with the suffix. In
addition a dot file, a file which name is started with "." is also ignored.
format
Format of the map data; currently the formats recognized are sun, which is a subset of the Sun
automounter map format, hesiod, for hesiod filesys entries and amd for amd formated map entries.
If the format is left unspecified, it defaults to sun for all map types except hesiod unless it is
a top level amd mount that has a configuration entry for the mount point path, in which case the
format used is amd.
map
Name of the map to use. This is an absolute UNIX pathname for maps of types file, dir, or
program, and the name of a database in the case for maps of type yp, nisplus, or hesiod or the dn
of an LDAP entry for maps of type ldap.
options
Any remaining command line arguments without leading dashes (-) are taken as options (-o) to
mount. Arguments with leading dashes are considered options for the maps and are passed to
automount (8).
The sun format supports the following options:
-Dvariable=value
Replace variable with value in map substitutions.
-strict
Treat errors when mounting file systems as fatal. This is important when multiple file
systems should be mounted (`multimounts'). If this option is given, no file system is
mounted at all if at least one file system can't be mounted.
[no]browse
This is an autofs specific option that is a pseudo mount option and so is given without a
leading dash. Use of the browse option pre-creates mount point directories for indirect
mount maps so the map keys can be seen in a directory listing without being mounted. Use of
this option can cause performance problem if the indirect map is large so it should be used
with caution. The internal program default is to enable browse mode for indirect mounts but
the default installed configuration overrides this by setting BROWSE_MODE to "no" because
of the potential performance problem.
nobind This is an autofs specific option that is a pseudo mount option and so is given without a
leading dash. It may be used either in the master map entry (so it effects all the map
entries) or with individual map entries to prevent bind mounting of local NFS filesystems.
For direct mount maps the option is only effective if specified on the first direct map
entry and is applied to all direct mount maps in the master map. It is ignored if given on
subsequent direct map entries. It may be used on individual map entries of both types. Bind
mounting of NFS file systems can also be prevented for specific map entrys by adding the
"port=" mount option to the entries.
symlink
This option makes bind mounting use a symlink instead of an actual bind mount. It is an
autofs specific option that is a pseudo mount option and so is given without a leading
dash. It may be used with indirect map entries only, either in the master map (so it
effects all map entries) or with individual map entries. The option is ignored for direct
mounts and non-root offest mount entries.
-r, --random-multimount-selection
Enables the use of ramdom selection when choosing a host from a list of replicated servers.
This option is applied to this mount only, overriding the global setting that may be
specified on the command line.
-w, --use-weight-only
Use only specified weights for server selection where more than one server is specified in
the map entry. If no server weights are given then each available server will be tried in
the order listed, within proximity.
-t, --timeout <seconds>
Set the expire timeout for map entries. This option can be used to override the global
default given either on the command line or in the configuration.
-n, --negative-timeout <seconds>
Set the timeout for caching failed key lookups. This option can be used to override the
global default given either on the command line or in the configuration.
BUILTIN MAP -hosts
If "-hosts" is given as the map then accessing a key under the mount point which corresponds to a
hostname will allow access to the exports of that host. The hosts map cannot be dynamically updated and
requires a HUP signal to be sent to the daemon for it to check hosts for an update. Due to possible
hierarchic dependencies within a mount tree, it might not be completely updated during the HUP signal
processing.
For example, with an entry in the master map of /net -hosts accessing /net/myserver will mount exports
from myserver on directories below /net/myserver.
NOTE: mounts done from a hosts map will be mounted with the "nosuid,nodev,intr" options unless overridden
by explicily specifying the "suid", "dev" or "nointr" options in the master map entry.
LDAP MAPS
If the map type ldap is specified the mapname is of the form [//servername/]dn, where the optional
servername is the name of the LDAP server to query, and dn is the Distinguished Name of a subtree to
search for map entries. The old style ldap:servername:mapname is also understood. Alternatively, the
type can be obtained from the Name Service Switch configuration, in which case the map name alone must be
given.
If no schema is set in the autofs configuration then autofs will check each of the commonly used schema
for a valid entry and if one is found it will used for subsequent lookups.
There are three common schemas in use:
nisMap
Entries in the nisMap schema are nisObject objects in the specified subtree, where the cn
attribute is the key (the wildcard key is "/"), and the nisMapEntry attribute contains the
information used by the automounter.
automountMap
The automountMap schema has two variations that differ in the attribute used for the map key.
Entries in the automountMap schema are automount objects in the specified subtree, where the cn or
automountKey attribute (depending on local usage) is the key (the wildcard key is "/"), and the
automountInformation attribute contains the information used by the automounter. Note that the cn
attribute is case insensitive.
The object classes and attributes used for accessing automount maps in LDAP can be changed by setting
entries in the autofs configuration located in /etc/default/autofs.conf.
NOTE: If a schema is given in the configuration then all the schema configuration values must be set,
any partial schema specification will be ignored.
For amd format maps a different schema is used:
amdMap
The amdmap schema contains attributes amdmapName, amdmapKey and amdmapValue where amdmapName
contains the name of the containing map, amdmapKey contains the map key and amdmapValue contains
the map entry.
LDAP AUTHENTICATION, ENCRYPTED AND CERTIFIED CONNECTIONS
LDAP authenticated binds, TLS encrypted connections and certification may be used by setting appropriate
values in the autofs authentication configuration file and configuring the LDAP client with appropriate
settings. The default location of this file is /etc/autofs_ldap_auth.conf.
If this file exists it will be used to establish whether TLS or authentication should be used.
An example of this file is:
<?xml version="1.0" ?>
<autofs_ldap_sasl_conf
usetls="yes"
tlsrequired="no"
authrequired="no"
authtype="DIGEST-MD5"
user="xyz"
secret="abc"
/>
If TLS encryption is to be used the location of the Certificate Authority certificate must be set within
the LDAP client configuration in order to validate the server certificate. If, in addition, a certified
connection is to be used then the client certificate and private key file locations must also be
configured within the LDAP client.
In OpenLDAP these may be configured in the ldap.conf file or in the per-user configuration. For example
it may be sensible to use the system wide configuration for the location of the Certificate Authority
certificate and set the location of the client certificate and private key in the per-user configuration.
The location of these files and the configuration entry requirements is system dependent so the
documentation for your installation will need to be consulted to get further information.
See autofs_ldap_auth.conf (5) for more information.
EXAMPLE
/- auto.data
/home /etc/auto.home
/mnt yp:mnt.map
This will generate two mountpoints for /home and /mnt and install direct mount triggers for each entry in
the direct mount map auto.data. All accesses to /home will lead to the consultation of the map in
/etc/auto.home and all accesses to /mnt will consult the NIS map mnt.map. All accesses to paths in the
map auto.data will trigger mounts when they are accessed and the Name Service Switch configuration will
be used to locate the source of the map auto.data.
SEE ALSO
automount(8), autofs(5), autofs(8), autofs.conf(5), autofs_ldap_auth.conf(5)
AUTHOR
This manual page was written by Christoph Lameter <chris@waterf.org>, for the Debian GNU/Linux system.
Edited by <hpa@transmeta.com> and Ian Kent <raven@themaw.net> .
11 Apr 2006 AUTO.MASTER(5)