chiark / gitweb /
man: mention /proc/self/mountinfo in systemd.mount(5)
[elogind.git] / man / systemd.mount.xml
index 70170bb..f319cf7 100644 (file)
@@ -9,16 +9,16 @@
   Copyright 2010 Lennart Poettering
 
   systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
   (at your option) any later version.
 
   systemd is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-  General Public License for more details.
+  Lesser General Public License for more details.
 
-  You should have received a copy of the GNU General Public License
+  You should have received a copy of the GNU Lesser General Public License
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 -->
 
@@ -44,7 +44,7 @@
 
         <refnamediv>
                 <refname>systemd.mount</refname>
-                <refpurpose>systemd mount configuration files</refpurpose>
+                <refpurpose>Mount unit configuration</refpurpose>
         </refnamediv>
 
         <refsynopsisdiv>
                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                 which define the execution environment the
                 <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
-                binary is executed in.</para>
+                binary is executed in, and in
+                <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                which define the way the processes are
+                terminated. Note that the User= and Group= options are
+                not particularly useful for mount units specifying a
+                <literal>Type=</literal> option or using configuration
+                not specified in <filename>/etc/fstab</filename>;
+                <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                will refuse options that aren't listed in
+                <filename>/etc/fstab</filename> if it is not run as
+                UID 0.</para>
 
                 <para>Mount units must be named after the mount point
                 directories they control. Example: the mount point
                 mounting. See
                 <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 
-                <para>If an mount point is beneath another mount point
+                <para>If a mount point is beneath another mount point
                 in the file system hierarchy, a dependency between both
                 units is created automatically.</para>
 
-                <para>Mount points created at runtime independent on
-                unit files or <filename>/etc/fstab</filename> will be
+                <para>Mount points created at runtime (independently of
+                unit files or <filename>/etc/fstab</filename>) will be
                 monitored by systemd and appear like any other mount
-                unit in systemd.</para>
+                unit in systemd.
+                See <filename>/proc/self/mountinfo</filename> description
+                in <citerefentry><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+                </para>
+
+                <para>Some file systems have special semantics as API
+                file systems for kernel-to-userspace and
+                userspace-to-userpace interfaces. Some of them may not
+                be changed via mount units, and cannot be disabled.
+                For a longer discussion see <ulink
+                url="http://www.freedesktop.org/wiki/Software/systemd/APIFileSystems">API
+                File Systems</ulink>.</para>
         </refsect1>
 
         <refsect1>
-                <title><filename>fstab</filename></title>
+                <title><filename>/etc/fstab</filename></title>
 
                 <para>Mount 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>
+                for details). Mounts listed in
+                <filename>/etc/fstab</filename> will be converted into
+                native units dynamically at boot and when the
+                configuration of the system manager is reloaded. See
+                <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                for details about the conversion.</para>
 
                 <para>When reading <filename>/etc/fstab</filename> a
                 few special mount options are understood by systemd
                 which influence how dependencies are created for mount
-                points from <filename>/etc/fstab</filename>. If
-                <option>comment=systemd.mount</option> is specified as
-                mount option, then systemd will create a dependency of
-                type <option>Wants</option> from either
+                points from <filename>/etc/fstab</filename>. systemd
+                will create a dependency of type
+                <option>Wants</option> from either
                 <filename>local-fs.target</filename> or
                 <filename>remote-fs.target</filename>, depending
                 whether the file system is local or remote. If
-                <option>comment=systemd.automount</option> is set, an
-                automount unit will be created for the file system. See
+                <option>x-systemd.automount</option> is set, an
+                automount unit will be created for the file
+                system. See
                 <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                for details.</para>
+                for details. If
+                <option>x-systemd.device-timeout=</option> is
+                specified it may be used to configure how long systemd
+                should wait for a device to show up before giving up
+                on an entry from
+                <filename>/etc/fstab</filename>. Specify a time in
+                seconds or explicitly specify a unit as
+                <literal>s</literal>, <literal>min</literal>,
+                <literal>h</literal>, <literal>ms</literal>.</para>
 
                 <para>If a mount point is configured in both
-                <filename>/etc/fstab</filename> and a unit file, the
-                configuration in the latter takes precedence.</para>
+                <filename>/etc/fstab</filename> and a unit file that
+                is stored below <filename>/usr</filename> the former
+                will take precedence. If the unit file is stored below
+                <filename>/etc</filename> it will take
+                precedence. This means: native unit files take
+                precedence over traditional configuration files, but
+                this is superseded by the rule that configuration in
+                <filename>/etc</filename> will always take precedence
+                over configuration in
+                <filename>/usr</filename>.</para>
         </refsect1>
 
         <refsect1>
                 supervises. A number of options that may be used in
                 this section are shared with other unit types. These
                 options are documented in
-                <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
+                <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                and
+                <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
                 options specific to the [Mount] section of mount
                 units are the following:</para>
 
                                 <term><varname>Where=</varname></term>
                                 <listitem><para>Takes an absolute path
                                 of a directory of the mount point. If
-                                the mount point is not existing at
+                                the mount point does not exist at the
                                 time of mounting, it is created. This
                                 string must be reflected in the unit
                                 file name. (See above.) This option is
 
                                 <listitem><para>Mount options to use
                                 when mounting. This takes a comma
-                                seperated list of options. This
+                                separated list of options. This
                                 setting is optional.</para></listitem>
                         </varlistentry>
 
                                 will be terminated forcibly via
                                 SIGTERM, and after another delay of
                                 this time with SIGKILL. (See
-                                <option>KillMode=</option> below.)
+                                <option>KillMode=</option> in
+                                <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.)
                                 Takes a unit-less value in seconds, or
                                 a time span value such as "5min
                                 20s". Pass 0 to disable the timeout
                                 logic. Defaults to
-                                60s.</para></listitem>
+                                90s.</para></listitem>
                         </varlistentry>
+                </variablelist>
 
+                <para>Check
+                <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                and
+                <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                for more settings.</para>
+        </refsect1>
+
+        <refsect1>
+                <title>Compatibility Options</title>
+
+                <para>The following option is also available in the
+                <literal>[Mount]</literal> section, but exists purely
+                for compatibility reasons and should not be used in
+                newly written mount files.</para>
+
+                <variablelist>
                         <varlistentry>
-                                <term><varname>KillMode=</varname></term>
-                                <listitem><para>Specifies how
-                                processes of this mount shall be
-                                killed. One of
-                                <option>control-group</option>,
-                                <option>process-group</option>,
-                                <option>process</option>,
-                                <option>none</option>.</para>
-
-                                <para>This option is mostly equivalent
-                                to the <option>KillMode=</option>
-                                option of service files. See
+                                <term><varname>FsckPassNo=</varname></term>
+
+                                <listitem><para>The pass number for
+                                the file system checking service for
+                                this mount. See
                                 <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
-                                for details.</para></listitem>
+                                for more information on this setting.
+                                </para></listitem>
                         </varlistentry>
                 </variablelist>
         </refsect1>
                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                          <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>mount</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-fstab-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                   </para>
         </refsect1>