automount - manage autofs mount points
program is used to manage mount points for autofs, the
inlined Linux automounter. automount
works by reading the
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 inactivity.
- -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
- -M <seconds>, --master-wait
- Set the maximum time to wait for the master map to become
available if it cannot be read at program start.
- -n <seconds>, --negative-timeout
- 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 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.
- -f, --foreground
- Run the daemon in the foreground and log to stderr instead
- -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
- With no parameters, list information about the configured
automounter maps, then exit.
If the dumpmaps option is given and is followed by two parameters,
"<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
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 directories, 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 entries 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 appened to
options given in a master map entry depending on the APPEND_OPTIONS
- -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.
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
- -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 NOTES).
takes one optional argument, the name of the master map to use.
- 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 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 running 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 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.
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
http://vger.kernel.org/vger-lists.html#autofs for information about the list.
H. Peter Anvin <email@example.com> and Ian Kent