AUTOMOUNT(8) System Manager's Manual AUTOMOUNT(8)
NAME
automount - manage autofs mount points
SYNOPSIS
automount [options] [master_map]
DESCRIPTION
The automount program is used to manage mount points for autofs, the
inlined Linux automounter. automount works by reading the
auto.master(5) map and sets up mount points for each entry in the mas-
ter map allowing them to be automatically mounted when accessed. The
file systems are then automatically umounted after a period of inactiv-
ity.
OPTIONS
-h, --help
Print brief help on program usage.
-p, --pid-file
Write the pid of the daemon to the specified file.
-t <seconds>, --timeout <seconds>
Set the global minimum timeout, in seconds, until directories
are unmounted. The default is 10 minutes. Setting the timeout to
zero disables umounts completely. The internal program default
is 10 minutes, but the default installed configuration overrides
this and sets the timeout to 5 minutes to be consistent with
earlier autofs releases.
-M <seconds>, --master-wait <seconds>
Set the maximum time to wait for the master map to become avail-
able if it cannot be read at program start.
-n <seconds>, --negative-timeout <seconds>
Set the default timeout for caching failed key lookups. The de-
fault 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 debugging messages for all autofs managed mounts.
-Dvariable=value, --define variable=value
Define a global macro substitution variable. Global definitions
are over-ridden macro definitions of the same name specified in
mount entries.
-S, --systemd-service
Used when running the automounter as a systemd service to ensure
log entry format is consistent with the log entry format when
running as a daemon.
-f, --foreground
Run the daemon in the foreground and log to stderr instead of
syslog."
-r, --random-multimount-selection
Enables the use of random selection when choosing a host from a
list of replicated servers.
-m, --dumpmaps [<map type> <map name>]
With no parameters, list information about the configured auto-
mounter maps, then exit.
If the dumpmaps option is given and is followed by two parame-
ters, "<map type> <map name>" then simple "<key, value>" pairs
that would be read in by a map read are printed to stdout if the
given map type and map name are found in the map configuration.
If the map is an LDAP map and there is more than one map of same
name in different base dns only the first map encountered by
autofs will be listed. Similarly, if the map is a file map and
there is more than one map of the same name in different direc-
tories, only the first map encountered will be listed.
If the map type is an old style multi-map and any one of the map
names in the multi-map entry matches the given map name the en-
tries that would be used by autofs for the whole multi-map will
be listed.
-O, --global-options
Allows the specification of global mount options used for all
master map entries. These options will either replace or be ap-
pended 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 val-
ues 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 ba-
sic 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 configu-
ration then attempting to set logging to basic logging, by using
alert, crit, err or emerg won't stop the verbose logging. Howev-
er, setting logging to debug will lead to everything (debug log-
ging) 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 pro-
cesses with working directories within these mounts (see NOTES).
ARGUMENTS
automount takes one optional argument, the name of the master map to
use.
master_map
Location for autofs master map that defines autofs managed mount
points and the mount maps they will use. The default is
auto.master.
NOTES
If the automount daemon catches a USR1 signal, it will umount all cur-
rently unused autofs managed mounted file systems and continue running
(forced expire). If it catches the TERM signal it will umount all un-
used autofs managed mounted file systems and exit if there are no re-
maining 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 dae-
mon 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 auto-
mount managed filesystems are found mounted when autofs is started they
will be recovered 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 run-
ning is used be aware that autofs currently may not function correctly
for certain types of automount maps. The mounts of the separate 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 pro-
cesses whose working directory is within unlinked automounted directo-
ries will not get the correct pwd from the system. This is because, af-
ter 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.
SEE ALSO
autofs(5), autofs(8), autofs.conf(5), auto.master(5), mount(8), aut-
ofs_ldap_auth.conf(5).
BUGS
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 <aut-
ofs@vger.kernel.org>. Visit http://vger.kernel.org/vger-lists.html#aut-
ofs for information about the list.
AUTHOR
H. Peter Anvin <hpa@transmeta.com> and Ian Kent <raven@themaw.net>.
12 Apr 2006 AUTOMOUNT(8)