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       automount - manage autofs mount points


       automount [options] [master_map]


       The  automount  program  is used to manage mount points for autofs, the
       inlined  Linux   automounter.    automount   works   by   reading   the
       auto.master(8)  map  and  sets  up  mount  points for each entry in the
       master map allowing them to be automatically mounted when accessed. The
       file  systems  are  then  automatically  umounted  after  a  period  of


       -h, --help
              Print brief help on program usage.

       -p, --pid-file
              Write the pid of the daemon to the specified file.

       -t, --timeout
              Set the global minimum timeout, in  seconds,  until  directories
              are unmounted. The default is 10 minutes. Setting the timeout to
              zero disables umounts completely.

       -n <seconds>, --negative-timeout <seconds>
              Set the default timeout for  caching  failed  key  lookups.  The
              default is 60 seconds.

       -v, --verbose
              Enables  logging of general status and progress messages for all
              autofs managed mounts.

       -d, --debug
              Enables logging of general status and progress messages as  well
              as debuging messages for all autofs managed mounts.

              Define  a global macro substitution variable. Global definitions
              are over-ridden macro definitions of the same name specified  in
              mount entries.

       -f, --foreground
              Run  the  daemon  in  the forground and log to stderr instead of

       -r, --random-multimount-selection
              Enables the use of ramdom selection when choosing a host from  a
              list of replicated servers.

       -O, --global-options
              Allows  the  specification  of global mount options used for all
              master map entries. These options  will  either  replace  or  be
              appened  to options given in a master map entry depending on the
              APPEND_OPTIONS configuration setting.

       -V, --version
              Display the version number, then exit.

       -l, --set-log-priority priority path [path,...]
              Set the daemon log  priority  to  the  specified  value.   Valid
              values  include  the  numbers  0-7, or the strings emerg, alert,
              crit, err, warning, notice, info, or debug. Log level debug will
              log  everything,  log  levels info, warn (or warning), or notice
              with enable the daemon verbose logging. Any other level will set
              basic  logging.  Note  that enabling debug or verbose logging in
              the autofs global configuration will override dynamic log  level
              changes.   For  example,  if  verbose  logging  is  set  in  the
              configuration then attempting to set logging to  basic  logging,
              by  using  alert,  crit,  err  or  emerg  won’t stop the verbose
              logging.  However,  setting  logging  to  debug  will  lead   to
              everything  (debug  logging) being logged witch can then also be
              disabled, returning the daemon to verbose logging.  This  option
              can  be  specified  to change the logging priority of an already
              running automount process.

       The path argument corresponds to the automounted path name as specified
       in the master map.

       -C, --dont-check-daemon
              Don’t check if the daemon is currently running (see NOTES).

       -F, --force
              Force  an  unlink umount of existing mounts under autofs managed
              mount  points  during  startup.  This  can  cause  problems  for
              processes  with  working  directories  within  these mounts (see


       automount takes one optional argument, the name of the  master  map  to

              Location for autofs master map that defines autofs managed mount
              points and  the  mount  maps  they  will  use.  The  default  is


       If  the  automount  daemon  catches  a  USR1 signal, it will umount all
       currently unused autofs  managed  mounted  file  systems  and  continue
       running  (forced expire).  If it catches the TERM signal it will umount
       all unused autofs managed mounted file systems and exit if there are no
       remaining  busy  file  systems.  If  autofs  has been compiled with the
       option to ignore busy mounts on exit it  will  exit  leaving  any  busy
       mounts  in  place  otherwise busy file systems will not be umounted and
       autofs will not exit.  Alternatively, if autofs has been compiled  with
       the  option  to enable forced shutdown then a USR2 signal to the daemon
       will cause all mounts to be umounted and any busy mounts to be forcibly
       umounted, including autofs mount point directories (summary execution).
       Note that the forced umount is  an  unlink  operation  and  the  actual
       umount  will  not  happen  in  the kernel until active file handles are
       released.  The daemon also responds to a HUP signal which  triggers  an
       update of the maps for each mount point.

       If  any autofs mount point directories are busy when the daemon is sent
       an exit signal the daemon will not exit. The exception to  this  is  if
       autofs  has  been  built  with  configure options to either ignore busy
       mounts at exit or force umount at exit. If the ignore  busy  mounts  at
       exit  option  is used the filesystems will be left in a catatonic (non-
       functional) state and can be manually umounted when they become unused.
       If  the  force  umount  at  exit option is used the filesystems will be
       umounted but the mount will not be released by the  kernel  until  they
       are  no  longer  in  use  by  the  processes  that  held them busy.  If
       automount managed filesystems are found mounted when autofs is  started
       they  will  be recoverd unless they are no longer present in the map in
       which case they need to umounted manually.

       If the option to disable the check to see  if  the  daemon  is  already
       running  is  used  be  aware  that  autofs  currently  may not function
       correctly for certain types  of  automount  maps.  The  mounts  of  the
       seperate  daemons might interfere with one another. The implications of
       running multiple daemon instances needs to be checked and tested before
       we can say this is supported.

       If  the  option  to  force  an unlink of mounts at startup is used then
       processes  whose  working  directory  is  within  unlinked  automounted
       directories  will  not  get  the  correct  pwd from the system. This is
       because, after the mount is unlinked from the mount tree, anything that
       needs  to  walk  back  up  the  mount tree to construct a path, such as
       getcwd(2) and the proc filesystem /proc/<pid>/cwd, cannot work  because
       the point from which the path is constructed has been detached from the
       mount tree.


       autofs(5),         autofs(8),         auto.master(5),         mount(8).


       Don’t know, I’ve fixed everything I know about.

       The documentation could be better.

       Please   report  other  bugs  along  with  a  detailed  description  to
       <>. For instructions on how to join the list and
       for archives visit


       H. Peter Anvin <> and Ian Kent <>.

                                  12 Apr 2006