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<refentry id="systemd.automount">
<refpurpose>Automount unit configuration</refpurpose>
<para>A unit configuration file whose name ends in
<literal>.automount</literal> encodes information about a file
system automount point controlled and supervised by
<para>This man page lists the configuration options specific to
this unit type. See
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.</para>
<para>Automount units must be named after the automount directories they control. Example: the automount point
<filename index="false">/home/lennart</filename> must be configured in a unit file
<filename>home-lennart.automount</filename>. For details about the escaping logic used to convert a file system
path to a unit name see
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Note that
automount units cannot be templated, nor is it possible to add multiple names to an automount unit by creating
additional symlinks to its unit file.</para>
<para>For each automount unit file a matching mount unit file (see
for details) must exist which is activated when the automount path
is accessed. Example: if an automount unit
<filename>home-lennart.automount</filename> is active and the user
accesses <filename>/home/lennart</filename> the mount unit
<filename>home-lennart.mount</filename> will be activated.</para>
<para>Automount units may be used to implement on-demand mounting
as well as parallelized mounting of file systems.</para>
<para>Note that automount units are separate from the mount itself, so you
should not set <varname>After=</varname> or <varname>Requires=</varname>
for mount dependencies here. For example, you should not set
<varname></varname> or similar on network
filesystems. Doing so may result in an ordering cycle.</para>
<para>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 user's service
<title>Automatic Dependencies</title>
<title>Implicit Dependencies</title>
<para>The following dependencies are implicitly added:</para>
<listitem><para>If an automount unit is beneath another mount unit in the
file system hierarchy, both a requirement and an ordering
dependency between both units are created automatically.</para></listitem>
<listitem><para>An implicit <varname>Before=</varname> dependency is created
between an automount unit and the mount unit it activates.</para></listitem>
<title>Default Dependencies</title>
<para>The following dependencies are added unless <varname>DefaultDependencies=no</varname> is set:</para>
<listitem><para>Automount units acquire automatic <varname>Before=</varname> and
<varname>Conflicts=</varname> on <filename></filename> in order to be stopped during
<listitem><para>Automount units automatically gain an <varname>After=</varname> dependency
on <filename></filename>, and a <varname>Before=</varname> dependency on
<para>Automount units may either be configured via unit files, or
via <filename>/etc/fstab</filename> (see
<citerefentry project='man-pages'><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for details).</para>
<para>For details how systemd parses
<filename>/etc/fstab</filename> see
<para>If an automount point is configured in both
<filename>/etc/fstab</filename> and a unit file, the configuration
in the latter takes precedence.</para>
<para>Automount 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:</para>
<variablelist class='unit-directives'>
<listitem><para>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.</para></listitem>
<listitem><para>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.</para></listitem>
<listitem><para>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
<title>See Also</title>
<citerefentry project='man-pages'><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>automount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,