Ubuntu Manpage: auto.master - Master Map for automounter

Provided by: autofs_5.1.2-1ubuntu3.2_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.

--mode <octal_mode>
Set the directory mode for the base location of the autofs mount point. If
this option is given, autofs will chmod that directory with this mode.

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.

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)