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[thirdparty/systemd.git] / man / systemd.automount.xml

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<refentry id="systemd.automount">
        <refentryinfo>
                <title>systemd.automount</title>
                <productname>systemd</productname>

                <authorgroup>
                        <author>
                                <contrib>Developer</contrib>
                                <firstname>Lennart</firstname>
                                <surname>Poettering</surname>
                                <email>lennart@poettering.net</email>
                        </author>
                </authorgroup>
        </refentryinfo>

        <refmeta>
                <refentrytitle>systemd.automount</refentrytitle>
                <manvolnum>5</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>systemd.automount</refname>
                <refpurpose>Automount unit configuration</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <para><filename><replaceable>automount</replaceable>.automount</filename></para>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para>A unit configuration file whose name ends in
                <literal>.automount</literal> encodes information
                about a file system automount point controlled and
                supervised by systemd.</para>

                <para>This man page lists the configuration options
                specific to this unit type. See
                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                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 noindex='true'>/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>.</para>

                <para>For each automount unit file a matching mount
                unit file (see
                <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                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>If an automount point is beneath another mount
                point in the file system hierarchy a dependency
                between both units is created automatically.</para>
        </refsect1>

        <refsect1>
                <title><filename>fstab</filename></title>

                <para>Automount units may either be configured via unit
                files, or via <filename>/etc/fstab</filename> (see
                <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                for details).</para>

                <para>For details how systemd parses
                <filename>/etc/fstab</filename> see
                <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>

                <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>
        </refsect1>

        <refsect1>
                <title>Options</title>

                <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'>

                        <varlistentry>
                                <term><varname>Where=</varname></term>
                                <listitem><para>Takes an absolute path
                                of a directory of the automount
                                point. If the automount point is not
                                existing 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>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>DirectoryMode=</varname></term>
                                <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>
                        </varlistentry>
                </variablelist>
        </refsect1>

        <refsect1>
                  <title>See Also</title>
                  <para>
                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>automount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                  </para>
        </refsect1>

</refentry>