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automount(8nfs) [ultrix man page]

automount(8nfs) 														   automount(8nfs)

       automount - automatically and transparently mounts and unmounts NFS file systems

       /usr/etc/automount [ -mnTv ] [ -D name= value ] [ -f master-file ]
       [ -M mount-directory ] [ -tl duration ] [ -tm interval ] [ -tw interval ]
       [ directory mapname [ - mount-options ]]

       The  command transparently mounts and unmounts NFS file systems on an as-needed basis.  It is useful for mounting file systems and directo-
       ries that are needed only occasionally, and it provides an alternative to using for NFS mounting file systems on client machines.

       The program can be started from the file or the command line.  The daemon forked by the program sleeps until a user attempts  to  access  a
       directory  that	is associated with an map.  The daemon then consults the appropriate map and mounts the NFS file system.  If the indicated
       directory has not already been created, the daemon creates it and removes it after automatic

       Local maps are typically located in the directory but can be placed in any directory.  You also can use the Yellow Pages  Service  to  dis-
       tribute	maps.  The maps indicate where to find the file system to be mounted, the local mount point, and mount options.  After a specified
       period of inactivity on a file system, 5 minutes by default, the daemon unmounts that file system.

       An individual automount map is either local or served by the Yellow Pages.  A system, however, can use both local and  Yellow  Pages  auto-
       mount  maps.  When a map is referenced, the program first looks for the designated mapname locally.  If it cannot find the mapname locally,
       it looks for a Yellow Pages map by that name.  The names of the maps are passed to from the command line, or from a master map.

       If the command line and the master map contain contradictory arguments, those on the command line take precedence.

       By default, the daemon mounts the remote file system under the directory and creates a symbolic link between the requested and  the  actual
       mount points.

       Conventionally, maps are files that are located in the directory with names that have the prefix They indicate which remote file systems to
       mount, where to mount them, and which options to use.

   The Master Map
       The program can consult a master map, which contains entries that point to other maps that can be either direct	or  indirect.	If  Yellow
       Pages is running, checks for the presence of a YP map named You are not required to run YP or have an map.  A master map can also be a file
       whose location is specified with the command line option.

       The master map provides with a list of maps, and with arguments that pertain to each of the maps.  Each line in the master map has the fol-
       lowing syntax:

       mount-point   map  [mount-options]

       o   Mount-point	is the full pathname of a local directory if the map argument is the name of an indirect map or the name of a special map.
	   If the map argument is the name of a direct map, the dummy directory ``/-'' is specified as the mount-point.

       o   Map is the name of the map the automount command uses to find the mount points and locations.  This can either be a filename, a YP  map
	   name, or a special map name.

       o   Mount-options is a list of options used to regulate the mounting of entries listed in map.

   Direct Maps
       Direct  maps  specify which remote file systems to mount locally and what the local mount points are. They do not point to other maps. They
       also can specify mount options.	Direct maps have the following syntax:

       key   [mount-options]   location

       o   Key is the full pathname of the mount point.

       o   Mount-options are the options for this specific mount. When present, these options override any mount options specified on the  command
	   line or in the master map.

       o   Location  is  the location of the resource being mounted, specified as: server:pathname.  Multiple location fields can be specified, in
	   which case sends multiple mount requests and mounts from the first server to respond.

   Indirect Maps
       Indirect maps have the same format as direct maps.  The only difference between a direct and an indirect map is that the key  in  a  direct
       map  is a full pathname, whereas the key in an indirect map is a simple name that does not begin with a slash.  (Remember that the indirect
       map as a whole has been associated with a directory specified in the master map or on the command line.	The entries  in  an  indirect  map
       list subdirectories that are individually mounted within the directory associated with the map.)

   Special Maps
       The map is a special map that is used to access all directories exported by a server to a client.

       The  following  command allows a client to access directories that are exported from any host in its file, the Yellow Pages hosts database,
       or the BIND database.
       # automount /net -hosts

       For example, suppose that and are both hosts on a local area network that is running Yellow Pages.  If the file	on  contains  the  command
       then users on can access any directories that exports to All of the exported directories are mounted under on

       The map, when indicated on the command line, cancels the map associated with the directory indicated.  It can be used to cancel a map spec-
       ified in the master map.  For example, invoking the command in the following manner causes the entry in to be ignored:
       # automount /net -null

   Pattern Matching
       The ampersand (&) is expanded into the key field in a map wherever it appears.  In the following example, the ampersand (&) expands to
	       #key	 mount_options	       location
	       oak			     &:/export/&

       The asterisk (*), when supplied as the key field, is recognized as the catch-all entry.	It is used to substitute for lines  that  are  all
       formatted  similarly.   Any  entry following the asterisk is ignored.  In the following example, the program uses the asterisk to match any
       hostname other than
	    #key	 mount_options	      location
	    oak 			      &:/export/&
	    *				      &:/home/&

   Environment Variables
       The value of an environment variable can be used within an automount map by prefixing a dollar sign ($) to its  name.   You  can  also  use
       braces  to  delimit the name of the variable from appended letters or digits.  The environment variables can be inherited from the environ-
       ment or can be explicitly defined with the command line option.

   Hierarchical Mounts
       You can mount different directories within an file system hierarchy from different servers.  For example, if you are mounting the file sys-
       tem on your machine, you can mount the various subdirectories within from different servers.

       In  the following example, the directories and are mounted from the machines host1, host2, host3, and host4 respectively.  When the root of
       the hierarchy is referenced, the program mounts the whole hierarchy.

		 /	   -ro	     host1:/usr/local 
		 /bin	   -ro	     host2:/usr/local/bin 
		 /src	   -ro	     host2:/usr/local/src 
		 /tools    -ro	     host2:/usr/src/tools

       Readability has been improved by splitting the entry into five lines and indenting the continuation lines.

       -m	 Ignores directory-mapname pairs listed in the Yellow Pages database.

       -n	 Disables dynamic mounts.  Lookups intercepted by the daemon succeed when the target file system has been previously mounted.

       -T	 Traces all NFS requests received by the daemon.  Information about the details of the request are expanded and sent  to  standard

       -v	 Logs status messages to the console.  (Stands for ``verbose.'')

       -D name=value
		 Defines an environment variable by assigning value to the variable.

       -f master-file
		 Uses  master-file  for  a  list of initial directory to mapname pairs, ahead of the Yellow Pages map.	If an entry exists in both
		 master-file and that specified in master-file is used since it is read first.	Similarly, entries on the command line take prece-
		 dence over master-file entries.  This technique can be used to replace entries in global maps with your own.

       -M mount-directory
		 Uses mount-directory instead of the default,

       -tl duration
		 Specifies a duration in seconds, that a file system is to remain mounted when not in use.  The default is 5 minutes.

       -tm interval
		 Specifies an interval in seconds, between attempts to mount a file system. The default is 30 seconds.

       -tw interval
		 Specifies  an interval in seconds, between attempts to unmount file systems that have exceeded their cached times. The default is
		 1 minute.

		 Specifies the mount options to be applied to all of the directories listed in mapname.  If mount options are listed in the speci-
		 fied  map,  they take precedence over these options.  Sending the SIGTERM signal to the daemon causes it to unmount all file sys-
		 tems that it has mounted, and to exit.

		 Sending the SIGHUP signal to the daemon causes it to reread the system mount table to update its  internal  record  of  currently
		 mounted  file	systems.  If a file system mounted with is unmounted by a command, should be forced to reread the system mount ta-

       Shell filename expansion does not apply to objects not currently mounted.

       Because is single-threaded, any request that is delayed by a slow or non-responding NFS server will delay all subsequent requests until the
       delayed request has been completed.

       The following is a sample map:
       # mount-point	       mapname		 mount-options
       /net		       -hosts
       /home		       auto.indirect	 -rw
       /-	 -ro,intr
       The following is a typical indirect map:
       # key		   mount-options	 location
       john					 merge:/home/merge/john
       mary					 stripe:/home/stripe/mary
       fred					 blur:/usr/staff/fred
       The following is a typical direct map:
       # key		   mount-options	 location
       /usr/source	   -ro			 merge:/usr/src/proto
       /usr/local				 blur:/usr/bin/tools
       The  following  is  a  sample  indirect map that specifies multiple mount locations for the file system The file system is mounted from the
       first server to respond to the request.
       reference	   -ro		  earl:/usr/src/ref

       Directory where automounted file systems reside

See Also
       mount(8), mount(8nfs), umount(8)
       Guide to the Network File System

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