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System Administration Guide, Volume 3

Master Autofs Map

The auto_master map associates a directory with a map. It is a master list specifying all the maps that autofs should check. The following example shows what an auto_master file could contain.

Example 31-1 Sample /etc/auto_master File


# Master map for automounter 
# 
+auto_master 
/net            -hosts           -nosuid,nobrowse 
/home           auto_home        -nobrowse 
/xfn            -xfn
/-              auto_direct     -ro

This example shows the generic auto_master file with one addition for the auto_direct map. Each line in the master map /etc/auto_master has the following syntax:

mount-point map-name [ mount-options ]

mount-point

mount-point is the full (absolute) path name of a directory. If the directory does not exist, autofs creates it if possible. If the directory exists and is not empty, mounting on it hides its contents. In this case, autofs issues a warning.

The notation /- as a mount point indicates that the map in question is a direct map, and no particular mount point is associated with the map as a whole.

map-name

map-name is the map autofs uses to find directions to locations, or mount information. If the name is preceded by a slash (/), autofs interprets the name as a local file. Otherwise, autofs searches for the mount information using the search specified in the name service switch configuration file (/etc/nsswitch.conf). Special maps are also used for /net and /xfn (see "Mount Point /net" and "Mount Point /xfn").

mount-options

mount-options is an optional, comma-separated list of options that apply to the mounting of the entries specified in map-name, unless the entries in map-name list other options. Options for each specific type of file system are listed in the mount man page for that file system (for example, see the mount_nfs(1M) man page for NFS specific mount options). For NFS specific mount points, the bg (background) and fg (foreground) options do not apply.

A line beginning with # is a comment. Everything that follows until the end of the line is ignored.

To split long lines into shorter ones, put a backslash (\) at the end of the line. The maximum number of characters of an entry is 1024.

Note -

If the same mount point is used in two entries, the first entry is used by the automount command. The second entry is ignored.

Mount Point /home

The mount point /home is the directory under which the entries listed in /etc/auto_home (an indirect map) are to be mounted.

Note -

Autofs runs on all computers and supports /net and /home (automounted home directories) by default. These defaults can be overridden by entries in the NIS auto.master map or NIS+ auto_master table, or by local editing of the /etc/auto_master file.

Mount Point /net

Autofs mounts under the directory /net all the entries in the special map -hosts. This is a built-in map that uses only the hosts database. For example, if the computer gumbo is in the hosts database and it exports any of its file systems, the command: 


%cd /net/gumbo

changes the current directory to the root directory of the computer gumbo. Autofs can mount only the exported file systems of host gumbo, that is, those on a server available to network users as opposed to those on a local disk. Therefore, all the files and directories on gumbo might not be available through /net/gumbo.

With the /net method of access, the server name is in the path and is location dependent. If you want to move an exported file system from one server to another, the path might no longer work. Instead, you should set up an entry in a map specifically for the file system you want rather than use /net.

Note -

Autofs checks the server's export list only at mount time. After a server's file systems are mounted, autofs does not check with the server again until the server's file systems are automatically unmounted. Therefore, newly exported file systems are not "seen" until the file systems on the client are unmounted and then remounted.

Mount Point /xfn

This mount point provides the autofs directory structure for the resources that are shared through the FNS name space (see the Solaris Naming Setup and Configuration Guide for more information about FNS).