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automount(1M)		System Administration Commands		 automount(1M)

       automount - install automatic mount points

       /usr/sbin/automount [-t duration] [-v]

       The  automount  utility	installs autofs	mount points and associates an
       automount map with each mount point. The	autofs	file  system  monitors
       attempts	 to  access  directories  within  it  and  notifies  the auto-
       mountd(1M) daemon. The daemon uses the map to  locate  a	 file  system,
       which  it  then mounts at the point of reference	within the autofs file
       system.	A map can be assigned to an autofs mount using an entry	in the
       /etc/auto_master	map or a direct	map.

       If  the	file system is not accessed within an appropriate interval (10
       minutes by default), the	automountd daemon unmounts the file system.

       The file	/etc/auto_master determines the	locations of all autofs	 mount
       points. By default, this	file contains four entries:

       # Master	map for	automounter
       /net	     -hosts    -nosuid
       /home	     auto_home
       /xfn	     -xfn

       The +auto_master	entry is a reference to	an external NIS	or NIS+	master
       map. If one exists, then	its entries are	read as	if  they  occurred  in
       place  of  the  +auto_master entry. The remaining entries in the	master
       file specify a directory	on which an autofs mount will be made followed
       by the automounter map to be associated with it.	Optional mount options
       may be supplied as an optional third field in the  each	entry.	 These
       options	are  used for any entries in the map that do not specify mount
       options explicitly. The automount command is usually run	without	 argu-
       ments.  It  compares the	entries	/etc/auto_master with the current list
       of  autofs mounts in /etc/mnttab	and adds, removes  or  updates	autofs
       mounts  to  bring the /etc/mnttab up to date with the /etc/auto_master.
       At boot time it installs	all autofs mounts from the master map.	Subse-
       quently,	 it may	be run to install autofs mounts	for new	entries	in the
       master map or the direct	map, or	to perform unmounts for	 entries  that
       have been removed from these maps.

       The following options are supported:

       - t duration
	     Specifies a duration, in seconds, that a file system is to	remain
	     mounted when not in use. The default is 10	minutes.

       -v    Verbose mode.  Notifies of	autofs mounts, unmounts, or other non-
	     essential information.

   Map Entry Format
       A simple	map entry (mapping) takes the form:

       key [ -mount-options ] location ...

       where key is the	full pathname of the directory to mount	when used in a
       direct map, or the simple name of a subdirectory	in  an	indirect  map.
       mount-options  is a comma-separated list	of mount options, and location
       specifies a file	system from which the directory	may be mounted.	In the
       case of a simple	NFS mount, the options that can	be  used are as	speci-
       fied in mount_nfs(1M), and location takes the form:


       host is the name	of the host from which to mount	the file  system,  and
       pathname	is the absolute	pathname of the	directory to mount.

       Options to other	file systems are documented on the other  mount_* ref-
       erence manual pages, for	example, mount_cachefs(1M).

   Replicated File Systems
       Multiple	location fields	can be specified for replicated	NFS file  sys-
       tems, in	which case  automount and the kernel will each try to use that
       information to increase availability. If	the read-only flag is  set  in
       the map entry, automount	mounts a list of locations that	the kernel may
       use, sorted by several criteria.	 When a	server does not	 respond,  the
       kernel  will switch to an alternate server.  The	sort ordering of auto-
       mount is	used to	determine how the next server is chosen. If the	 read-
       only  flag  is  not set,	automount will mount the best single location,
       chosen by the same sort ordering, and new  servers will only be	chosen
       when  an	 unmount  has been possible, and a remount is done. Servers on
       the same	local subnet are given the strongest preference,  and  servers
       on  the	local  net  are	 given the second strongest preference.	 Among
       servers equally far away, response times	will determine the order if no
       weighting factors (see below) are used.

       If the list includes server locations using both	the NFS	Version	2 Pro-
       tocol and the NFS Version 3 Protocol,  automount	 will  choose  only  a
       subset of the server locations on the list, so that all entries will be
       the same	protocol.  It will choose servers with the  NFS	Version	3 Pro-
       tocol  so  long	as an NFS Version 2 Protocol server  on	a local	subnet
       will not	be ignored. See	the System Administration Guide:  IP  Services
       for additional details.

       If each location	in the list shares the same pathname then a single lo-
       cation may be used with a comma-separated list of hostnames:


       Requests	for a server may be weighted, with the	weighting  factor  ap-
       pended to the server name as an integer in parentheses. Servers without
       a weighting are assumed to have a value of zero (most likely to be  se-
       lected).	  Progressively	higher values decrease the chance of being se-
       lected. In the example,

       man -ro alpha,bravo,charlie(1),delta(4):/usr/man

       hosts alpha and bravo have the highest priority;	 host  delta  has  the

	Server proximity takes priority	in the selection process. In the exam-
       ple above, if the server	delta is on the	same network  segment  as  the
       client,	but  the  others are on	different network segments, then delta
       will be selected; the weighting value is	ignored.   The	weighting  has
       effect  only when selecting between servers with	the same network prox-

       In cases	where each server has a	different export point,	the  weighting
       can still be applied. For example:

       man -ro alpha:/usr/man  bravo,charlie(1):/usr/share/man

       A  mapping  can be continued across input lines by escaping the NEWLINE
       with a backslash	(\) Comments begin with	a number sign (#) and  end  at
       the subsequent <NEWLINE>.

   Map Key Substitution
       The  ampersand  (&) character is	expanded to the	value of the key field
       for the entry in	which it occurs. In this case:

       jane sparcserver:/home/&

       the & expands to	jane.

   Wildcard Key
       The asterisk (*)	character, when	supplied as the	key field,  is	recog-
       nized as	the catch-all entry. Such an entry will	match any key not pre-
       viously matched.	For instance, if the following entry appeared  in  the
       indirect	map for	/config:

       *	 &:/export/config/&

       this  would allow automatic mounts in /config of	any remote file	system
       whose location could be specified as:


   Variable Substitution
       Client specific variables can be	used within an automount map. For  in-
       stance,	if  $HOST  appeared within a map, automount would expand it to
       its current value for the client's host name. Supported variables are:

       ARCH	     The application  architec-	  The architecture  name.  For
		     ture  is  derived from the	  example,  "sun4"  on a sun4u
		     output of uname -m		  machine.
       CPU	     The output	of uname -p	  The processor	type.
						  For example, "sparc"
       HOST	     The output	of uname -n	  The host name.
						  For example, "biggles"
       OSNAME	     The output	of uname -s	  The OS name.
						  For example, "SunOS"
       OSREL	     The output	of uname -r	  The OS release name.
						  For example "5.3"
       OSVERS	     The output	of uname -v	  The OS version.
						  For example, "beta1.0"
       NATISA	     The output	of isainfo -n	  The native instruction set
						  architecture for the system.
						  For example, "sparcv9"

       If a reference needs to be protected from affixed characters,  you  can
       surround	the variable name with curly braces ({}).

   Multiple Mounts
       A multiple mount	entry takes the	form:

       key [-mount-options] [[mountpoint] [-mount-options] location...]...

       The initial /[mountpoint] is optional for the first mount and mandatory
       for all subsequent mounts.  The optional	mountpoint is taken as a path-
       name  relative  to the directory	named by key. If mountpoint is omitted
       in the first occurrence,	a mountpoint of	/ (root) is implied.

       Given an	entry in the indirect map for /src

       beta	-ro\
	 /	     svr1,svr2:/export/src/beta	 \
	 /1.0	     svr1,svr2:/export/src/beta/1.0  \
	 /1.0/man    svr1,svr2:/export/src/beta/1.0/man

       All offsets must	exist on the server under beta.	automount  will	 auto-
       matically  mount	 /src/beta,  /src/beta/1.0, and	 /src/beta/1.0/man, as
       needed, from either svr1	or  svr2, whichever host is  nearest  and  re-
       sponds first.

   Other File System Types
       The automounter assumes NFS mounts as a default file system type. Other
       file system types can be	described using	the fstype mount option. Other
       mount  options  specific	 to this file system type can be combined with
       the fstype option. The location field must contain information specific
       to  the	file system type. If the location field	begins with a slash, a
       colon character must be prepended, for instance,	to  mount  a  CD  file

       cdrom -fstype=hsfs,ro   :/dev/sr0

       or to perform an	autofs mount:

       src   -fstype=autofs    auto_src

       Note:  Use this procedure only if you are not using Volume Manager.

       Mounts  using  CacheFS are most useful when applied to an entire	map as
       map defaults. The following entry in the	master	map  describes	cached
       home  directory	mounts.	  It assumes the default location of the cache
       directory, /cache.

       /home auto_home	     -fstype=cachefs,backfstype=nfs

       See the	NOTES section for information on option	inheritance.

   Indirect Maps
       An indirect map allows you to specify mappings for  the	subdirectories
       you wish	to mount under the directory indicated on the command line. In
       an indirect map,	each key consists of a simple name that	refers to  one
       or more file systems that are to	be mounted as needed.

   Direct Maps
       Entries	in  a  direct  map  are	 associated directly with autofs mount
       points. Each key	is the full pathname of	an autofs mount	point. The di-
       rect map	as a whole is not associated with any single directory.

   Included Maps
       The  contents of	another	map can	be included within a map with an entry
       of the form


       If mapname begins with a	slash, it is assumed to	be the pathname	 of  a
       local  file.  Otherwise,	 the  location of the map is determined	by the
       policy of the name service switch according to the entry	for the	 auto-
       mounter in /etc/nsswitch.conf, such as

       automount: files	nis

       If  the name service is files, then the name is assumed to be that of a
       local file in /etc. If the key being searched for is not	found  in  the
       included	map, the search	continues with the next	entry.

   Special Maps
       There  are  three  special maps available: -hosts, -xfn,	and -null. The
       -hosts map is used with the /net	directory and assumes that the map key
       is  the	hostname  of an	NFS server.  The automountd daemon dynamically
       constructs a map	entry from the server's	list of	exported file systems.
       References  to  a  directory under /net/hermes will refer to the	corre-
       sponding	directory relative to hermes root.

       The -xfn	map is used to mount the initial context of the	Federated Nam-
       ing Service (FNS) namespace under the /xfn directory. For more informa-
       tion on FNS, see	fns(5),	fns_initial_context(5),	 fns_policies(5),  and
       the Federated Naming Service Guide.

       The  -null map cancels a	previous map for the directory indicated. This
       is most useful in the  /etc/auto_master	for  cancelling	 entries  that
       would otherwise be inherited from the +auto_master include entry. To be
       effective, the -null entries must be inserted before the	 included  map

   Executable Maps
       Local maps that have the	execute	bit set	in their file permissions will
       be executed by the automounter and provided with	a key to be looked  up
       as an argument. The executable map is expected to return	the content of
       an automounter map entry	on its stdout or no output if the entry	cannot
       be determined. A	direct map cannot be made executable.

   Configuration and the auto_master Map
       When initiated without arguments, automount consults the	master map for
       a list of autofs	mount points and their	maps.  It  mounts  any	autofs
       mounts  that  are  not already mounted, and unmounts autofs mounts that
       have been removed from the master map or	direct map.

       The master map is assumed to be called auto_master and its location  is
       determined  by  the name	service	switch policy. Normally	the master map
       is located initially as a local file /etc/auto_master.

       The Solaris 2.6 release supports	browsability of	 indirect  maps.  This
       allows  all of the potential mount points to be visible,	whether	or not
       they are	mounted. The  -nobrowse	option can be added to any indirect
	autofs map to disable browsing.	For example:

       /net	-hosts	    -nosuid,nobrowse
       /home	auto_home

       In this case, any hostnames would only be visible in  /net  after  they
       are  mounted,  but  all	potential  mount points	would be visible under
       /home.  The  -browse option enables browsability	of  autofs  file  sys-
       tems. This is the default for all indirect maps.

       The following exit values are returned:

	0    Successful	completion.

       1     An	error occurred.

	     master automount map.

	     map to support automounted	home directories.

	     the name service switch configuration file.

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcsu			   |

       isainfo(1),  ls(1), uname(1), automountd(1M), mount(1M),	mount_cachefs(
       1M),  mount_nfs(1M),  attributes(5),  fns(5),   fns_initial_context(5),
       fns_policies(5),	nfssec(5)

       System Administration Guide: IP Services

       autofs  mount points must not be	hierarchically related.	automount does
       not allow an autofs mount point to be  created  within  another	autofs

       Since  each  direct  map	 entry results in a new	autofs mount such maps
       should be kept short.

       Entries in both direct and indirect maps	can be modified	at  any	 time.
       The  new	information is used when automountd next uses the map entry to
       do a mount.

       New entries added to a master map or direct map will not	be useful  un-
       til  the	 automount  command is run to install them as new autofs mount
       points. New entries added to an indirect	map may	be used	immediately.

       As of the Solaris 2.6 release, a	listing	(see ls(1)) of the  autofs di-
       rectory	associated  with an indirect map shows all potential mountable
       entries.	The attributes associated with the potential mountable entries
       are  temporary. The real	file system attributes will only be shown once
       the file	system has been	mounted.

       Default mount options can be assigned to	an entire map  when  specified
       as  an optional third field in the master map. These options apply only
       to map entries that have	no mount options. Note that map	entities  with
       options	override  the default options, as at this time,	the options do
       not concatenate.	 The concatenation feature is planned for a future re-

       When  operating	on a map that invokes an NFS mount, the	default	number
       of retries for the automounter is 0, that is, a single  mount  attempt,
       with  no	 retries.   Note  that this is	       significantly different
       from the	default	(10000)	for the	mount_nfs(1M) utility.

       The Network Information Service (NIS) was formerly known	as Sun	Yellow
       Pages (YP). The functionality of	the two	remains	the same.

SunOS 5.9			  1 Nov	1999			 automount(1M)


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