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<refnamediv>
<refname>systemd.unit</refname>
- <refpurpose>systemd unit configuration files</refpurpose>
+ <refpurpose>Unit configuration</refpurpose>
</refnamediv>
<refsynopsisdiv>
- <para><filename>systemd.service</filename>,
- <filename>systemd.socket</filename>,
- <filename>systemd.device</filename>,
- <filename>systemd.mount</filename>,
- <filename>systemd.automount</filename>,
- <filename>systemd.swap</filename>,
- <filename>systemd.target</filename>,
- <filename>systemd.path</filename>,
- <filename>systemd.timer</filename>,
- <filename>systemd.snapshot</filename></para>
+ <para><filename><replaceable>service</replaceable>.service</filename>,
+ <filename><replaceable>socket</replaceable>.socket</filename>,
+ <filename><replaceable>device</replaceable>.device</filename>,
+ <filename><replaceable>mount</replaceable>.mount</filename>,
+ <filename><replaceable>automount</replaceable>.automount</filename>,
+ <filename><replaceable>swap</replaceable>.swap</filename>,
+ <filename><replaceable>target</replaceable>.target</filename>,
+ <filename><replaceable>path</replaceable>.path</filename>,
+ <filename><replaceable>timer</replaceable>.timer</filename>,
+ <filename><replaceable>snapshot</replaceable>.snapshot</filename></para>
+
+ <para><literallayout><filename>/etc/systemd/system/*</filename>
+<filename>/run/systemd/system/*</filename>
+<filename>/usr/lib/systemd/system/*</filename>
+<filename>...</filename>
+ </literallayout></para>
+
+ <para><literallayout><filename>/etc/systemd/user/*</filename>
+<filename>/run/systemd/user/*</filename>
+<filename>/usr/lib/systemd/user/*</filename>
+<filename>...</filename>
+ </literallayout></para>
</refsynopsisdiv>
<refsect1>
<para>A unit configuration file encodes information
about a service, a socket, a device, a mount point, an
automount point, a swap file or partition, a start-up
- target, a file system path or a timer controlled and
+ target, a file system path, or a timer controlled and
supervised by
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The
syntax is inspired by <ulink
inspired by Microsoft Windows
<filename>.ini</filename> files.</para>
- <para>This man pages lists the common configuration
+ <para>This man page lists the common configuration
options of all the unit types. These options need to
- be configured in the [Unit] resp. [Install]
- section of the unit files.</para>
+ be configured in the [Unit] or [Install]
+ sections of the unit files.</para>
<para>In addition to the generic [Unit] and [Install]
- sections described here, each unit should have a
+ sections described here, each unit may have a
type-specific section, e.g. [Service] for a service
unit. See the respective man pages for more
- information.</para>
+ information:
+ <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
+ </para>
+
+ <para>Unit files are loaded from a set of paths
+ determined during compilation, described in the next section.
+ </para>
<para>Unit files may contain additional options on top
of those listed here. If systemd encounters an unknown
<para>Time span values encoded in unit files can be
written in various formats. A stand-alone number
specifies a time in seconds. If suffixed with a time
- unit, the unit is honored. A concatenation of
- multiple values with units is supported, in which case
- the values are added up. Example: "50" refers to 50
+ unit, the unit is honored. A concatenation of multiple
+ values with units is supported, in which case the
+ values are added up. Example: "50" refers to 50
seconds; "2min 200ms" refers to 2 minutes plus 200
milliseconds, i.e. 120200ms. The following time units
- are understood: s, min, h, d, w, ms, us.</para>
+ are understood: s, min, h, d, w, ms, us. For details
+ see
+ <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
<para>Empty lines and lines starting with # or ; are
ignored. This may be used for commenting. Lines ending
line while reading and the backslash is replaced by a
space character. This may be used to wrap long lines.</para>
- <para>If a line starts with <option>.include</option>
- followed by a file name, the specified file will be
- read as if its contents were listed in place of the
- <option>.include</option> directive.</para>
-
<para>Along with a unit file
- <filename>foo.service</filename> a directory
+ <filename>foo.service</filename> the directory
<filename>foo.service.wants/</filename> may exist. All
- units symlinked from such a directory are implicitly
- added as dependencies of type
+ unit files symlinked from such a directory are
+ implicitly added as dependencies of type
<varname>Wanted=</varname> to the unit. This is useful
to hook units into the start-up of other units,
- without having to modify their unit configuration
- files. For details about the semantics of
- <varname>Wanted=</varname> see below. The preferred
- way to create symlinks in the
- <filename>.wants/</filename> directory of a service is
- with the <command>enable</command> command of the
+ without having to modify their unit files. For details
+ about the semantics of <varname>Wanted=</varname> see
+ below. The preferred way to create symlinks in the
+ <filename>.wants/</filename> directory of a unit file
+ is with the <command>enable</command> command of the
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool which reads information from the [Install]
- section of unit files. (See below.)</para>
+ section of unit files (see below). A similar
+ functionality exists for <varname>Requires=</varname>
+ type dependencies as well, the directory suffix is
+ <filename>.requires/</filename> in this case.</para>
+
+ <para>Along with a unit file
+ <filename>foo.service</filename> a directory
+ <filename>foo.service.d/</filename> may exist. All
+ files with the suffix <filename>.conf</filename> from
+ this directory will be parsed after the file itself is
+ parsed. This is useful to alter or add configuration
+ settings to a unit, without having to modify their
+ unit files. Make sure that the file that is included
+ has the appropriate section headers before any
+ directive.</para>
+
+ <para>If a line starts with <option>.include</option>
+ followed by a file name, the specified file will be
+ parsed at this point. Make sure that the file that is
+ included has the appropriate section headers before
+ any directives.</para>
<para>Note that while systemd offers a flexible
dependency system between units it is recommended to
- use this functionality only sparsely and instead rely
+ use this functionality only sparingly and instead rely
on techniques such as bus-based or socket-based
- activation which makes dependencies implicit, which
- both results in a simpler and more flexible
- system.</para>
+ activation which make dependencies implicit, resulting
+ in a both simpler and more flexible system.</para>
<para>Some unit names reflect paths existing in the
file system name space. Example: a device unit
and no file by that name is found, systemd will look
for <filename>getty@.service</filename> and
instantiate a service from that configuration file if
- it is found. To refer to the instance string from
+ it is found.</para>
+
+ <para>To refer to the instance string from
within the configuration file you may use the special
<literal>%i</literal> specifier in many of the
- configuration options. Other specifiers that may be
- used are <literal>%n</literal>, <literal>%N</literal>,
- <literal>%p</literal>, <literal>%P</literal> and
- <literal>%I</literal>, for the full unit name, the
- unescaped unit name, the prefix name, the unescaped
- prefix name and the unescaped instance name,
- respectively. The prefix name here refers to the
- string before the @, i.e. "getty" in the example
- above, where "tty3" is the instance name.</para>
+ configuration options. See below for details.</para>
<para>If a unit file is empty (i.e. has the file size
0) or is symlinked to <filename>/dev/null</filename>
<ulink
url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
Stability Promise</ulink>.</para>
+
+ </refsect1>
+
+ <refsect1>
+ <title>Unit Load Path</title>
+
+ <para>Unit files are loaded from a set of paths
+ determined during compilation, described in the two
+ tables below. Unit files found in directories higher
+ in the hierarchy override files with the same name
+ lower in the hierarchy, thus allowing overrides.
+ </para>
+
+ <para>When systemd is running in user mode
+ (<option>--user</option>) and the variable
+ <varname>$SYSTEMD_UNIT_PATH</varname> is set, this
+ contents of this variable overrides the unit load
+ path.
+ </para>
+
+ <table>
+ <title>
+ Load path when running in system mode (<option>--system</option>).
+ </title>
+
+ <tgroup cols='2'>
+ <colspec colname='path' />
+ <colspec colname='expl' />
+ <thead>
+ <row>
+ <entry>Path</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><filename>/run/systemd/generator.early</filename></entry>
+ <entry>Generated units (early)</entry>
+ </row>
+ <row>
+ <entry><filename>/etc/systemd/system</filename></entry>
+ <entry>Local configuration</entry>
+ </row>
+ <row>
+ <entry><filename>/run/systemd/systemd</filename></entry>
+ <entry>Volatile units</entry>
+ </row>
+ <row>
+ <entry><filename>/run/systemd/generator</filename></entry>
+ <entry>Generated units (middle)</entry>
+ </row>
+ <row>
+ <entry><filename>/usr/local/lib/systemd/system</filename></entry>
+ <entry>Units for local packages</entry>
+ </row>
+ <row>
+ <entry><filename>/usr/lib/systemd/system</filename></entry>
+ <entry>Units for installed packages</entry>
+ </row>
+ <row>
+ <entry><filename>/run/systemd/generator.late</filename></entry>
+ <entry>Generated units (late)</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <table>
+ <title>
+ Load path when running in session mode (<option>--user</option>).
+ </title>
+
+ <tgroup cols='2'>
+ <colspec colname='path' />
+ <colspec colname='expl' />
+ <thead>
+ <row>
+ <entry>Path</entry>
+ <entry>Description</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><filename>/tmp/systemd-generator.early.<replaceable>XXXXXX</replaceable></filename></entry>
+ <entry>Generated units (early)</entry>
+ </row>
+ <row>
+ <entry><filename>/etc/systemd/user</filename></entry>
+ <entry>Local configuration</entry>
+ </row>
+ <row>
+ <entry><filename>/run/systemd/user</filename></entry>
+ <entry>Volatile units</entry>
+ </row>
+ <row>
+ <entry><filename>/tmp/systemd-generator.<replaceable>XXXXXX</replaceable></filename></entry>
+ <entry>Generated units (middle)</entry>
+ </row>
+ <row>
+ <entry><filename>/usr/local/lib/systemd/user</filename></entry>
+ <entry>Units for local packages</entry>
+ </row>
+ <row>
+ <entry><filename>/usr/lib/systemd/user</filename></entry>
+ <entry>Units for installed packages</entry>
+ </row>
+ <row>
+ <entry><filename>/tmp/systemd-generator.late.<replaceable>XXXXXX</replaceable></filename></entry>
+ <entry>Generated units (late)</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <para>Additional units might be loaded into systemd
+ ("linked") from directories not on the unit load
+ path. See the <command>link</command> command for
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
+ </para>
</refsect1>
<refsect1>
carries generic information about the unit that is not
dependent on the type of unit:</para>
- <variablelist>
- <varlistentry>
- <term><varname>Names=</varname></term>
-
- <listitem><para>Additional names for
- this unit. The names listed here must
- have the same suffix (i.e. type) as
- the unit file name. This option may be
- specified more than once, in which
- case all listed names are used. Note
- that this option is different from the
- <varname>Alias=</varname> option from
- the [Install] section mentioned
- below. See below for details.</para>
- </listitem>
- </varlistentry>
+ <variablelist class='unit-directives'>
<varlistentry>
<term><varname>Description=</varname></term>
name.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>Documentation=</varname></term>
+ <listitem><para>A space separated list
+ of URIs referencing documentation for
+ this unit or its
+ configuration. Accepted are only URIs
+ of the types
+ <literal>http://</literal>,
+ <literal>https://</literal>,
+ <literal>file:</literal>,
+ <literal>info:</literal>,
+ <literal>man:</literal>. For more
+ information about the syntax of these
+ URIs see
+ <citerefentry><refentrytitle>uri</refentrytitle><manvolnum>7</manvolnum></citerefentry>. The
+ URIs should be listed in order of
+ relevance, starting with the most
+ relevant. It is a good idea to first
+ reference documentation that explains
+ what the unit's purpose is, followed
+ by how it is configured, followed by
+ any other related documentation. This
+ option may be specified more than once
+ in which case the specified list of
+ URIs is merged. If the empty string is
+ assigned to this option the list is
+ reset and all prior assignments will
+ have no effect.</para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>Requires=</varname></term>
<varname>Requires=</varname> in order
to achieve a system that is more
robust when dealing with failing
- services.</para></listitem>
- </varlistentry>
+ services.</para>
+ <para>Note that dependencies of this
+ type may also be configured outside of
+ the unit configuration file by
+ adding a symlink to a
+ <filename>.requires/</filename> directory
+ accompanying the unit file. For
+ details see above.</para></listitem>
+ </varlistentry>
<varlistentry>
<term><varname>RequiresOverridable=</varname></term>
<listitem><para>Similar to
<varname>Requires=</varname>
- resp. <varname>RequiresOverridable=</varname>. However,
+ and <varname>RequiresOverridable=</varname>, respectively. However,
if a unit listed here is not started
already it will not be started and the
transaction fails
the transaction as a whole. This is
the recommended way to hook start-up
of one unit to the start-up of another
- unit. Note that dependencies of this
+ unit.</para>
+
+ <para>Note that dependencies of this
type may also be configured outside of
the unit configuration file by
adding a symlink to a
details see above.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>BindsTo=</varname></term>
+
+ <listitem><para>Configures requirement
+ dependencies, very similar in style to
+ <varname>Requires=</varname>, however
+ in addition to this behavior it also
+ declares that this unit is stopped
+ when any of the units listed suddenly
+ disappears. Units can suddenly,
+ unexpectedly disappear if a service
+ terminates on its own choice, a device
+ is unplugged or a mount point
+ unmounted without involvement of
+ systemd.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>PartOf=</varname></term>
+
+ <listitem><para>Configures dependencies
+ similar to <varname>Requires=</varname>,
+ but limited to stopping and restarting
+ of units. When systemd stops or restarts
+ the units listed here, the action is
+ propagated to this unit.
+ Note that this is a one way dependency -
+ changes to this unit do not affect the
+ listed units.
+ </para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>Conflicts=</varname></term>
<varname>Before=</varname>. If two
units have no ordering dependencies
between them they are shut down
- resp. started up simultaneously, and
+ or started up simultaneously, and
no ordering takes
place. </para></listitem>
</varlistentry>
</varlistentry>
<varlistentry>
- <term><varname>RecursiveStop=</varname></term>
+ <term><varname>PropagatesReloadTo=</varname></term>
+ <term><varname>ReloadPropagatedFrom=</varname></term>
+
+ <listitem><para>Lists one or more
+ units where reload requests on the
+ unit will be propagated to/on the
+ other unit will be propagated
+ from. Issuing a reload request on a
+ unit will automatically also enqueue a
+ reload request on all units that the
+ reload request shall be propagated to
+ via these two
+ settings.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>RequiresMountsFor=</varname></term>
+
+ <listitem><para>Takes a space
+ separated list of absolute paths. Automatically
+ adds dependencies of type
+ <varname>Requires=</varname> and
+ <varname>After=</varname> for all
+ mount units required to access the
+ specified path.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>OnFailureIsolate=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option> the
+ unit listed in
+ <varname>OnFailure=</varname> will be
+ enqueued in isolation mode, i.e. all
+ units that are not its dependency will
+ be stopped. If this is set only a
+ single unit may be listed in
+ <varname>OnFailure=</varname>. Defaults
+ to
+ <option>false</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>IgnoreOnIsolate=</varname></term>
<listitem><para>Takes a boolean
- argument. If <option>true</option> and
- the unit stops without being requested
- by the user, all units
- depending on it will be stopped as
- well. (e.g. if a service exits or
- crashes on its own behalf, units using
- it will be stopped) Note that normally
- if a unit stops without a user request,
- units depending on it will not be
- terminated. Only if the user requested
- shutdown of a unit, all units depending
- on that unit will be shut down as well
- and at the same time. Defaults to
+ argument. If <option>true</option>
+ this unit will not be stopped when
+ isolating another unit. Defaults to
<option>false</option>.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>IgnoreOnSnapshot=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ this unit will not be included in
+ snapshots. Defaults to
+ <option>true</option> for device and
+ snapshot units, <option>false</option>
+ for the others.</para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>StopWhenUnneeded=</varname></term>
<listitem><para>Takes a boolean
argument. If <option>true</option>
this unit can only be activated
- (resp. deactivated) indirectly. In
+ or deactivated indirectly. In
this case explicit start-up
- (resp. termination) requested by the
+ or termination requested by the
user is denied, however if it is
- started (resp. stopped) as a
+ started or stopped as a
dependency of another unit, start-up
- (resp. termination) will succeed. This
+ or termination will succeed. This
is mostly a safety feature to ensure
that the user does not accidentally
activate units that are not intended
ones.</para></listitem>
</varlistentry>
- <varlistentry>
- <term><varname>IgnoreDependencyFailure=</varname></term>
-
- <listitem><para>Takes a boolean
- argument. If <option>true</option> and
- a requirement dependency of this unit
- fails to start up this unit will be
- started nonetheless, ignoring that
- failure. If <option>false</option>
- (the default) and a dependency unit
- fails the unit will immediately fail
- too and the job is removed.</para></listitem>
- </varlistentry>
-
<varlistentry>
<term><varname>JobTimeoutSec=</varname></term>
<varlistentry>
<term><varname>ConditionPathExists=</varname></term>
+ <term><varname>ConditionPathExistsGlob=</varname></term>
+ <term><varname>ConditionPathIsDirectory=</varname></term>
+ <term><varname>ConditionPathIsSymbolicLink=</varname></term>
+ <term><varname>ConditionPathIsMountPoint=</varname></term>
+ <term><varname>ConditionPathIsReadWrite=</varname></term>
+ <term><varname>ConditionDirectoryNotEmpty=</varname></term>
+ <term><varname>ConditionFileNotEmpty=</varname></term>
+ <term><varname>ConditionFileIsExecutable=</varname></term>
<term><varname>ConditionKernelCommandLine=</varname></term>
+ <term><varname>ConditionVirtualization=</varname></term>
+ <term><varname>ConditionSecurity=</varname></term>
+ <term><varname>ConditionCapability=</varname></term>
+ <term><varname>ConditionHost=</varname></term>
+ <term><varname>ConditionACPower=</varname></term>
+ <term><varname>ConditionNull=</varname></term>
<listitem><para>Before starting a unit
verify that the specified condition is
- true. With
+ true. If it is not true the starting
+ of the unit will be skipped, however
+ all ordering dependencies of it are
+ still respected. A failing condition
+ will not result in the unit being
+ moved into a failure state. The
+ condition is checked at the time the
+ queued start job is to be
+ executed.</para>
+
+ <para>With
<varname>ConditionPathExists=</varname>
- a file existance condition can be
+ a file existence condition is
checked before a unit is started. If
the specified absolute path name does
- not exist startup of a unit will not
- actually happen, however the unit is
- still useful for ordering purposes in
- this case. The condition is checked at
- the time the queued start job is to be
- executed. If the absolute path name
- passed to
+ not exist the condition will
+ fail. If the absolute path name passed
+ to
<varname>ConditionPathExists=</varname>
is prefixed with an exclamation mark
- (!), the test is negated, and the unit
- only started if the path does not
- exist. Similarly
+ ('!'), the test is negated, and the unit
+ is only started if the path does not
+ exist.</para>
+
+ <para><varname>ConditionPathExistsGlob=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>,
+ but checks for the existence of at
+ least one file or directory matching
+ the specified globbing pattern.</para>
+
+ <para><varname>ConditionPathIsDirectory=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a
+ directory.</para>
+
+ <para><varname>ConditionPathIsSymbolicLink=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a symbolic
+ link.</para>
+
+ <para><varname>ConditionPathIsMountPoint=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a mount
+ point.</para>
+
+ <para><varname>ConditionPathIsReadWrite=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether the underlying
+ file system is readable and writable
+ (i.e. not mounted
+ read-only).</para>
+
+ <para><varname>ConditionDirectoryNotEmpty=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a non-empty
+ directory.</para>
+
+ <para><varname>ConditionFileNotEmpty=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and refers to a regular file
+ with a non-zero size.</para>
+
+ <para><varname>ConditionFileIsExecutable=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists, is a regular file and marked
+ executable.</para>
+
+ <para>Similar,
<varname>ConditionKernelCommandLine=</varname>
may be used to check whether a
specific kernel command line option is
set (or if prefixed with the
exclamation mark unset). The argument
must either be a single word, or an
- assignment (i.e. two words, seperated
- by the equality sign). In the former
- case the kernel command line is search
- for the word appearing as is, or as
- left hand side of an assignment. In
- the latter case the exact assignment
- is looked for with right and left hand
- side matching. If multiple conditions
- are specified the unit will be
- executed iff at least one of them
- apply (i.e. a logical OR is
- applied).</para></listitem>
+ assignment (i.e. two words, separated
+ '='). In the former
+ case the kernel command line is
+ searched for the word appearing as is,
+ or as left hand side of an
+ assignment. In the latter case the
+ exact assignment is looked for with
+ right and left hand side
+ matching.</para>
+
+ <para><varname>ConditionVirtualization=</varname>
+ may be used to check whether the
+ system is executed in a virtualized
+ environment and optionally test
+ whether it is a specific
+ implementation. Takes either boolean
+ value to check if being executed in
+ any virtualized environment, or one of
+ <varname>vm</varname> and
+ <varname>container</varname> to test
+ against a generic type of
+ virtualization solution, or one of
+ <varname>qemu</varname>,
+ <varname>kvm</varname>,
+ <varname>vmware</varname>,
+ <varname>microsoft</varname>,
+ <varname>oracle</varname>,
+ <varname>xen</varname>,
+ <varname>bochs</varname>,
+ <varname>chroot</varname>,
+ <varname>openvz</varname>,
+ <varname>lxc</varname>,
+ <varname>lxc-libvirt</varname>,
+ <varname>systemd-nspawn</varname> to
+ test against a specific
+ implementation. If multiple
+ virtualization technologies are nested
+ only the innermost is considered. The
+ test may be negated by prepending an
+ exclamation mark.</para>
+
+ <para><varname>ConditionSecurity=</varname>
+ may be used to check whether the given
+ security module is enabled on the
+ system. Currently the only recognized
+ value is <varname>selinux</varname>.
+ The test may be negated by prepending
+ an exclamation
+ mark.</para>
+
+ <para><varname>ConditionCapability=</varname>
+ may be used to check whether the given
+ capability exists in the capability
+ bounding set of the service manager
+ (i.e. this does not check whether
+ capability is actually available in
+ the permitted or effective sets, see
+ <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+ for details). Pass a capability name
+ such as <literal>CAP_MKNOD</literal>,
+ possibly prefixed with an exclamation
+ mark to negate the check.</para>
+
+ <para><varname>ConditionHost=</varname>
+ may be used to match against the
+ host name or machine ID of the
+ host. This either takes a host name
+ string (optionally with shell style
+ globs) which is tested against the
+ locally set host name as returned by
+ <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ or a machine ID formatted as string
+ (see
+ <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
+ The test may be negated by prepending
+ an exclamation mark.</para>
+
+ <para><varname>ConditionACPower=</varname>
+ may be used to check whether the
+ system has AC power, or is exclusively
+ battery powered at the time of
+ activation of the unit. This takes a
+ boolean argument. If set to
+ <varname>true</varname> the condition
+ will hold only if at least one AC
+ connector of the system is connected
+ to a power source, or if no AC
+ connectors are known. Conversely, if
+ set to <varname>false</varname> the
+ condition will hold only if there is
+ at least one AC connector known and
+ all AC connectors are disconnected
+ from a power source.</para>
+
+ <para>Finally,
+ <varname>ConditionNull=</varname> may
+ be used to add a constant condition
+ check value to the unit. It takes a
+ boolean argument. If set to
+ <varname>false</varname> the condition
+ will always fail, otherwise
+ succeed.</para>
+
+ <para>If multiple conditions are
+ specified the unit will be executed if
+ all of them apply (i.e. a logical AND
+ is applied). Condition checks can be
+ prefixed with a pipe symbol (|) in
+ which case a condition becomes a
+ triggering condition. If at least one
+ triggering condition is defined for a
+ unit then the unit will be executed if
+ at least one of the triggering
+ conditions apply and all of the
+ non-triggering conditions. If you
+ prefix an argument with the pipe
+ symbol and an exclamation mark the
+ pipe symbol must be passed first, the
+ exclamation second. Except for
+ <varname>ConditionPathIsSymbolicLink=</varname>,
+ all path checks follow symlinks. If
+ any of these options is assigned the
+ empty string the list of conditions is
+ reset completely, all previous
+ condition settings (of any kind) will
+ have no effect.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>SourcePath=</varname></term>
+ <listitem><para>A path to a
+ configuration file this unit has been
+ generated from. This is primarily
+ useful for implementation of generator
+ tools that convert configuration from
+ an external configuration file format
+ into native unit files. Thus
+ functionality should not be used in
+ normal units.</para></listitem>
</varlistentry>
</variablelist>
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool during installation of a unit:</para>
- <variablelist>
+ <variablelist class='unit-directives'>
<varlistentry>
<term><varname>Alias=</varname></term>
time,
<command>systemctl enable</command>
will create symlinks from these names
- to the unit file name. Note that this
- is different from the
- <varname>Names=</varname> option from
- the [Unit] section mentioned above:
- The names from
- <varname>Names=</varname> apply
- unconditionally if the unit is
- loaded. The names from
- <varname>Alias=</varname> apply only
- if the unit has actually been
- installed with the
- <command>systemctl enable</command>
- command. Also, if systemd searches for a
- unit, it will discover symlinked alias
- names as configured with
- <varname>Alias=</varname>, but not
- names configured with
- <varname>Names=</varname> only. It is
- a common pattern to list a name in
- both options. In this case, a unit
- will be active under all names if
- installed, but also if not installed
- but requested explicitly under its
- main name.</para></listitem>
+ to the unit file name.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>WantedBy=</varname></term>
+ <term><varname>RequiredBy=</varname></term>
<listitem><para>Installs a symlink in
the <filename>.wants/</filename>
- subdirectory for a unit. This has the
+ or <filename>.requires/</filename>
+ subdirectory for a unit, respectively. This has the
effect that when the listed unit name
is activated the unit listing it is
activated
</varlistentry>
</variablelist>
+ <para>The following specifiers are interpreted in the
+ Install section: %n, %N, %p, %i, %U, %u, %m, %H, %b.
+ For their meaning see the next section.
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>Specifiers</title>
+
+ <para>Many settings resolve specifiers which may be
+ used to write generic unit files referring to runtime
+ or unit parameters that are replaced when the unit
+ files are loaded. The following specifiers are
+ understood:</para>
+
+ <table>
+ <title>Specifiers available in unit files</title>
+ <tgroup cols='3' align='left' colsep='1' rowsep='1'>
+ <colspec colname="spec" />
+ <colspec colname="mean" />
+ <colspec colname="detail" />
+ <thead>
+ <row>
+ <entry>Specifier</entry>
+ <entry>Meaning</entry>
+ <entry>Details</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>%n</literal></entry>
+ <entry>Full unit name</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%N</literal></entry>
+ <entry>Unescaped full unit name</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%p</literal></entry>
+ <entry>Prefix name</entry>
+ <entry>For instantiated units this refers to the string before the @. For non-instantiated units this refers to to the name of the unit with the type suffix removed.</entry>
+ </row>
+ <row>
+ <entry><literal>%P</literal></entry>
+ <entry>Unescaped prefix name</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%i</literal></entry>
+ <entry>Instance name</entry>
+ <entry>For instantiated units: this is the string between the @ character and the suffix.</entry>
+ </row>
+ <row>
+ <entry><literal>%I</literal></entry>
+ <entry>Unescaped instance name</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%f</literal></entry>
+ <entry>Unescaped file name</entry>
+ <entry>This is either the unescaped instance name (if applicable) with / prepended (if applicable), or the prefix name similarly prepended with /.</entry>
+ </row>
+ <row>
+ <entry><literal>%c</literal></entry>
+ <entry>Control group path of the unit</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%r</literal></entry>
+ <entry>Root control group path of systemd</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%R</literal></entry>
+ <entry>Parent directory of the root control group path of systemd</entry>
+ <entry></entry>
+ </row>
+ <row>
+ <entry><literal>%t</literal></entry>
+ <entry>Runtime socket dir</entry>
+ <entry>This is either <filename>/run</filename> (for the system manager) or <literal>$XDG_RUNTIME_DIR</literal> (for user managers).</entry>
+ </row>
+ <row>
+ <entry><literal>%u</literal></entry>
+ <entry>User name</entry>
+ <entry>This is the name of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry>
+ </row>
+ <row>
+ <entry><literal>%U</literal></entry>
+ <entry>User UID</entry>
+ <entry>This is the UID of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry>
+ </row>
+ <row>
+ <entry><literal>%h</literal></entry>
+ <entry>User home directory</entry>
+ <entry>This is the home directory of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry>
+ </row>
+ <row>
+ <entry><literal>%s</literal></entry>
+ <entry>User shell</entry>
+ <entry>This is the shell of the configured
+ user of the unit, or (if none is set) the user
+ running the systemd instance. If the user is
+ <literal>root</literal> (UID equal to 0), the
+ shell configured in account database is
+ ignored and <filename>/bin/sh</filename> is
+ always used.
+ </entry>
+ </row>
+ <row>
+ <entry><literal>%m</literal></entry>
+ <entry>Machine ID</entry>
+ <entry>The machine ID of the running system, formatted as string. See <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information.</entry>
+ </row>
+ <row>
+ <entry><literal>%b</literal></entry>
+ <entry>Boot ID</entry>
+ <entry>The boot ID of the running system, formatted as string. See <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry> for more information.</entry>
+ </row>
+ <row>
+ <entry><literal>%H</literal></entry>
+ <entry>Host name</entry>
+ <entry>The host name of the running system.</entry>
+ </row>
+ <row>
+ <entry><literal>%%</literal></entry>
+ <entry>Escaped %</entry>
+ <entry>Single percent sign.</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
</refsect1>
<refsect1>
<citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff