systemd.automount(5) — Linux manual page
SYSTEMD.AUTOMOUNT(5) systemd.automount SYSTEMD.AUTOMOUNT(5)
NAME
systemd.automount - Automount unit configuration
SYNOPSIS
automount.automount
DESCRIPTION
A unit configuration file whose name ends in ".automount" encodes
information about a file system automount point controlled and
supervised by systemd. Automount units may be used to implement
on-demand mounting as well as parallelized mounting of file
systems.
This man page lists the configuration options specific to this
unit type. See systemd.unit(5) for the common options of all unit
configuration files. The common configuration items are
configured in the generic [Unit] and [Install] sections. The
automount specific configuration options are configured in the
[Automount] section.
Automount units must be named after the automount directories
they control. Example: the automount point /home/lennart must be
configured in a unit file home-lennart.automount. For details
about the escaping logic used to convert a file system path to a
unit name see systemd.unit(5). Note that automount units cannot
be templated, nor is it possible to add multiple names to an
automount unit by creating symlinks to its unit file.
For each automount unit file a matching mount unit file (see
systemd.mount(5) for details) must exist which is activated when
the automount path is accessed. Example: if an automount unit
home-lennart.automount is active and the user accesses
/home/lennart the mount unit home-lennart.mount will be
activated.
Note that automount units are separate from the mount itself, so
you should not set After= or Requires= for mount dependencies
here. For example, you should not set After=network-online.target
or similar on network filesystems. Doing so may result in an
ordering cycle.
Note that automount support on Linux is privileged, automount
units are hence only available in the system service manager (and
root's user service manager), but not in unprivileged users'
service managers.
Note that automount units should not be nested. (The
establishment of the inner automount point would unconditionally
pin the outer mount point, defeating its purpose.)
AUTOMATIC DEPENDENCIES
Implicit Dependencies
The following dependencies are implicitly added:
• If an automount unit is beneath another mount unit in the
file system hierarchy, a requirement and ordering
dependencies are created to the on the unit higher in the
hierarchy.
• An implicit Before= dependency is created between an
automount unit and the mount unit it activates.
Default Dependencies
The following dependencies are added unless
DefaultDependencies=no is set:
• Automount units acquire automatic Before= and Conflicts= on
umount.target in order to be stopped during shutdown.
• Automount units automatically gain an After= dependency on
local-fs-pre.target, and a Before= dependency on
local-fs.target.
FSTAB
Automount units may either be configured via unit files, or via
/etc/fstab (see fstab(5) for details).
For details how systemd parses /etc/fstab see systemd.mount(5).
If an automount point is configured in both /etc/fstab and a unit
file, the configuration in the latter takes precedence.
OPTIONS
Automount unit files may include [Unit] and [Install] sections,
which are described in systemd.unit(5).
Automount unit files must include an [Automount] section, which
carries information about the file system automount points it
supervises. The options specific to the [Automount] section of
automount units are the following:
Where=
Takes an absolute path of a directory of the automount point.
If the automount point does not exist at time that the
automount point is installed, it is created. This string must
be reflected in the unit filename. (See above.) This option
is mandatory.
ExtraOptions=
Extra mount options to use when creating the autofs
mountpoint. This takes a comma-separated list of options.
This setting is optional. Note that the usual specifier
expansion is applied to this setting, literal percent
characters should hence be written as "%%".
Added in version 250.
DirectoryMode=
Directories of automount points (and any parent directories)
are automatically created if needed. This option specifies
the file system access mode used when creating these
directories. Takes an access mode in octal notation. Defaults
to 0755.
TimeoutIdleSec=
Configures an idle timeout. Once the mount has been idle for
the specified time, systemd will attempt to unmount. Takes a
unit-less value in seconds, or a time span value such as
"5min 20s". Pass 0 to disable the timeout logic. The timeout
is disabled by default.
Added in version 220.
Check systemd.unit(5), systemd.exec(5), and systemd.kill(5) for
more settings.
SEE ALSO
systemd(1), systemctl(1), systemd.unit(5), systemd.mount(5),
mount(8), automount(8), systemd.directives(7)
COLOPHON
This page is part of the systemd (systemd system and service
manager) project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have
a bug report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
systemd 257~devel SYSTEMD.AUTOMOUNT(5)
Pages that refer to this page: systemd(1), systemd-mount(1), systemd.mount(5), systemd.unit(5), systemd.directives(7), systemd.index(7), systemd.syntax(7)