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System Administration Guide, Volume 3

Direct Autofs Maps

A direct map is an automount point. With a direct map, there is a direct association between a mount point on the client and a directory on the server. Direct maps have a full path name and indicate the relationship explicitly. This is a typical /etc/auto_direct map: 


/usr/local          -ro \
   /bin                   ivy:/export/local/sun4 \
   /share                 ivy:/export/local/share \
   /src                   ivy:/export/local/src
   /usr/man         -ro   oak:/usr/man \
                          rose:/usr/man \
                          willow:/usr/man 
   /usr/games       -ro   peach:/usr/games 
   /usr/spool/news  -ro   pine:/usr/spool/news \
                          willow:/var/spool/news

Lines in direct maps have the following syntax:

key [ mount-options ] location

key

key is the path name of the mount point in a direct map.

mount-options

mount-options is the options you want to apply to this particular mount. They are required only if they differ from the map default. Options for each specific type of file system are listed in the mount man page for that file system (for example, see the mount_cachefs(1M) man page for CacheFS specific mount options).

location

location is the location of the file system, specified (one or more) as server:pathname for NFS file systems or :devicename for High Sierra file systems (HSFS).

Note -

The pathname should not include an automounted mount point; it should be the actual absolute path to the file system. For instance, the location of a home directory should be listed as server:/export/home/username, not as server:/home/username.

As in the master map, a line beginning with # is a comment. All the text that follows until the end of the line is ignored. Put a backslash at the end of the line to split long lines into shorter ones.

Of all the maps, the entries in a direct map most closely resemble the corresponding entries in /etc/vfstab (vfstab contains a list of all file systems to be mounted). An entry that appears in /etc/vfstab as: 


dancer:/usr/local - /usr/local/tmp nfs - yes ro

appears in a direct map as: 


/usr/local/tmp     -ro     dancer:/usr/local
Note -

No concatenation of options occurs between the automounter maps. Any options added to an automounter map override all options listed in maps that are searched earlier. For instance, options included in the auto_master map would be overridden by corresponding entries in any other map.

See "How Autofs Selects the Nearest Read-Only Files for Clients (Multiple Locations)" for other important features associated with this type of map.

Mount Point /-

In Example 31-1, the mount point /- tells autofs not to associate the entries in auto_direct with any specific mount point. Indirect maps use mount points defined in the auto_master file. Direct maps use mount points specified in the named map. (Remember, in a direct map the key, or mount point, is a full path name.)

An NIS or NIS+ auto_master file can have only one direct map entry because the mount point must be a unique value in the name space. An auto_master file that is a local file can have any number of direct map entries, as long as entries are not duplicated.