</refnamediv>
<refsynopsisdiv>
- <para><filename>systemd.service</filename></para>
- <para><filename>systemd.socket</filename></para>
- <para><filename>systemd.device</filename></para>
- <para><filename>systemd.mount</filename></para>
- <para><filename>systemd.automount</filename></para>
- <para><filename>systemd.swap</filename></para>
- <para><filename>systemd.target</filename></para>
+ <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>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>A unit configuration file encodes information
- about a service, a socket, a mount point, an automount
- point, a swap file or patition, or a start-up target
- controlled and supervised by systemd. The syntax is
- inspired by XDG <filename>.desktop</filename> files,
- which are in turn inspired by Windows
+ 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
+ supervised by
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The
+ syntax is inspired by <ulink
+ url="http://standards.freedesktop.org/desktop-entry-spec/latest/">XDG
+ Desktop Entry Specification</ulink> <filename>.desktop</filename> files, which are in turn
+ inspired by Microsoft Windows
<filename>.ini</filename> files.</para>
<para>This man pages lists the common configuration
- options of the various unit types.</para>
+ options of all the unit types. These options need to
+ be configured in the [Unit] resp. [Install]
+ section of the unit files.</para>
+
+ <para>In addition to the generic [Unit] and [Install]
+ sections described here, each unit should have a
+ type-specific section, e.g. [Service] for a service
+ unit. See the respective man pages for more
+ information.</para>
+
+ <para>Unit files may contain additional options on top
+ of those listed here. If systemd encounters an unknown
+ option it will write a warning log message but
+ continue loading the unit. If an option is prefixed
+ with <option>X-</option> it is ignored completely by
+ systemd. Applications may use this to include
+ additional information in the unit files.</para>
+
+ <para>Boolean arguments used in unit files can be
+ written in various formats. For positive settings the
+ strings <option>1</option>, <option>yes</option>,
+ <option>true</option> and <option>on</option> are
+ equivalent. For negative settings the strings
+ <option>0</option>, <option>no</option>,
+ <option>false</option> and <option>off</option> are
+ equivalent.</para>
+
+ <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
+ 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>
+
+ <para>Empty lines and lines starting with # or ; are
+ ignored. This may be used for commenting. Lines ending
+ in a backslash are concatenated with the following
+ 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.wants/</filename> may exist. All
+ units 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
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ tool which reads information from the [Install]
+ 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>Note that while systemd offers a flexible
+ dependency system between units it is recommended to
+ use this functionality only sparsely 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>
+
+ <para>Some unit names reflect paths existing in the
+ file system name space. Example: a device unit
+ <filename>dev-sda.device</filename> refers to a device
+ with the device node <filename>/dev/sda</filename> in
+ the file system namespace. If this applies a special
+ way to escape the path name is used, so that the
+ result is usable as part of a file name. Basically,
+ given a path, "/" is replaced by "-", and all
+ unprintable characters and the "-" are replaced by
+ C-style "\x20" escapes. The root directory "/" is
+ encoded as single dash, while otherwise the initial
+ and ending "/" is removed from all paths during
+ transformation. This escaping is reversible.</para>
+
+ <para>Optionally, units may be instantiated from a
+ template file at runtime. This allows creation of
+ multiple units from a single configuration file. If
+ systemd looks for a unit configuration file it will
+ first search for the literal unit name in the
+ filesystem. If that yields no success and the unit
+ name contains an @ character, systemd will look for a
+ unit template that shares the same name but with the
+ instance string (i.e. the part between the @ character
+ and the suffix) removed. Example: if a service
+ <filename>getty@tty3.service</filename> is requested
+ 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
+ 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>,
+ <literal>%I</literal>, <literal>%f</literal>,
+ <literal>%c</literal>, <literal>%r</literal>,
+ <literal>%R</literal> and <literal>%t</literal> for
+ the full unit name, the unescaped unit name, the
+ prefix name, the unescaped prefix name, the unescaped
+ instance name, the unescaped filename, the control
+ group path of the unit, the root control group path of
+ systemd, and the parent directory of the root control
+ cgroup path of systemd and the runtime socket dir,
+ respectively. The unescaped filename is either the
+ unescaped instance name (if set) with / prepended (if
+ necessary), or the prefix name similarly prepended
+ with /. The prefix name here refers to the string
+ before the @, i.e. "getty" in the example above, where
+ "tty3" is the instance name. The runtime socket
+ directory is either <filename>/run</filename> (for the
+ system manager) or <literal>$XDG_RUNTIME_DIR</literal>
+ (for user managers).</para>
+
+ <para>If a unit file is empty (i.e. has the file size
+ 0) or is symlinked to <filename>/dev/null</filename>
+ its configuration will not be loaded and it appears
+ with a load state of <literal>masked</literal>, and
+ cannot be activated. Use this as an effective way to
+ fully disable a unit, making it impossible to start it
+ even manually.</para>
+
+ <para>The unit file format is covered by the
+ <ulink
+ url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
+ Stability Promise</ulink>.</para>
</refsect1>
<refsect1>
<title>Options</title>
+ <para>Unit file may include a [Unit] section, which
+ carries generic information about the unit that is not
+ dependent on the type of unit:</para>
+
<variablelist>
+
<varlistentry>
- <term>Names=</term>
- <listitem>
- <para>Additional names for this unit. The names
- listed here mus have the same suffix (i.e. type)
- as the identifier name. This option may be
- specified more than once.</para>
- </listitem>
+ <term><varname>Description=</varname></term>
+ <listitem><para>A free-form string
+ describing the unit. This is intended
+ for use in UIs to show descriptive
+ information along with the unit
+ name.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Requires=</varname></term>
+
+ <listitem><para>Configures requirement
+ dependencies on other units. If this
+ unit gets activated, the units listed
+ here will be activated as well. If one
+ of the other units gets deactivated or
+ its activation fails, this unit will
+ be deactivated. This option may be
+ specified more than once, in which
+ case requirement dependencies for all
+ listed names are created. Note that
+ requirement dependencies do not
+ influence the order in which services
+ are started or stopped. This has to be
+ configured independently with the
+ <varname>After=</varname> or
+ <varname>Before=</varname> options. If
+ a unit
+ <filename>foo.service</filename>
+ requires a unit
+ <filename>bar.service</filename> as
+ configured with
+ <varname>Requires=</varname> and no
+ ordering is configured with
+ <varname>After=</varname> or
+ <varname>Before=</varname>, then both
+ units will be started simultaneously
+ and without any delay between them if
+ <filename>foo.service</filename> is
+ activated. Often it is a better choice
+ to use <varname>Wants=</varname>
+ instead of
+ <varname>Requires=</varname> in order
+ to achieve a system that is more
+ robust when dealing with failing
+ services.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>RequiresOverridable=</varname></term>
+
+ <listitem><para>Similar to
+ <varname>Requires=</varname>.
+ Dependencies listed in
+ <varname>RequiresOverridable=</varname>
+ which cannot be fulfilled or fail to
+ start are ignored if the startup was
+ explicitly requested by the user. If
+ the start-up was pulled in indirectly
+ by some dependency or automatic
+ start-up of units that is not
+ requested by the user this dependency
+ must be fulfilled and otherwise the
+ transaction fails. Hence, this option
+ may be used to configure dependencies
+ that are normally honored unless the
+ user explicitly starts up the unit, in
+ which case whether they failed or not
+ is irrelevant.</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term><varname>Requisite=</varname></term>
+ <term><varname>RequisiteOverridable=</varname></term>
+
+ <listitem><para>Similar to
+ <varname>Requires=</varname>
+ resp. <varname>RequiresOverridable=</varname>. However,
+ if a unit listed here is not started
+ already it will not be started and the
+ transaction fails
+ immediately.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Wants=</varname></term>
+
+ <listitem><para>A weaker version of
+ <varname>Requires=</varname>. A unit
+ listed in this option will be started
+ if the configuring unit is. However,
+ if the listed unit fails to start up
+ or cannot be added to the transaction
+ this has no impact on the validity of
+ 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
+ type may also be configured outside of
+ the unit configuration file by
+ adding a symlink to a
+ <filename>.wants/</filename> directory
+ accompanying the unit file. For
+ details see above.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>BindTo=</varname></term>
+
+ <listitem><para>Configures requirement
+ dependencies, very similar in style to
+ <varname>Requires=</varname>, however
+ in addition to this behaviour 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>Conflicts=</varname></term>
+
+ <listitem><para>Configures negative
+ requirement dependencies. If a unit
+ has a
+ <varname>Conflicts=</varname> setting
+ on another unit, starting the former
+ will stop the latter and vice
+ versa. Note that this setting is
+ independent of and orthogonal to the
+ <varname>After=</varname> and
+ <varname>Before=</varname> ordering
+ dependencies.</para>
+
+ <para>If a unit A that conflicts with
+ a unit B is scheduled to be started at
+ the same time as B, the transaction
+ will either fail (in case both are
+ required part of the transaction) or
+ be modified to be fixed (in case one
+ or both jobs are not a required part
+ of the transaction). In the latter
+ case the job that is not the required
+ will be removed, or in case both are
+ not required the unit that conflicts
+ will be started and the unit that is
+ conflicted is
+ stopped.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Before=</varname></term>
+ <term><varname>After=</varname></term>
+
+ <listitem><para>Configures ordering
+ dependencies between units. If a unit
+ <filename>foo.service</filename>
+ contains a setting
+ <option>Before=bar.service</option>
+ and both units are being started,
+ <filename>bar.service</filename>'s
+ start-up is delayed until
+ <filename>foo.service</filename> is
+ started up. Note that this setting is
+ independent of and orthogonal to the
+ requirement dependencies as configured
+ by <varname>Requires=</varname>. It is
+ a common pattern to include a unit
+ name in both the
+ <varname>After=</varname> and
+ <varname>Requires=</varname> option in
+ which case the unit listed will be
+ started before the unit that is
+ configured with these options. This
+ option may be specified more than
+ once, in which case ordering
+ dependencies for all listed names are
+ created. <varname>After=</varname> is
+ the inverse of
+ <varname>Before=</varname>, i.e. while
+ <varname>After=</varname> ensures that
+ the configured unit is started after
+ the listed unit finished starting up,
+ <varname>Before=</varname> ensures the
+ opposite, i.e. that the configured
+ unit is fully started up before the
+ listed unit is started. Note that when
+ two units with an ordering dependency
+ between them are shut down, the
+ inverse of the start-up order is
+ applied. i.e. if a unit is configured
+ with <varname>After=</varname> on
+ another unit, the former is stopped
+ before the latter if both are shut
+ down. If one unit with an ordering
+ dependency on another unit is shut
+ down while the latter is started up,
+ the shut down is ordered before the
+ start-up regardless whether the
+ ordering dependency is actually of
+ type <varname>After=</varname> or
+ <varname>Before=</varname>. If two
+ units have no ordering dependencies
+ between them they are shut down
+ resp. started up simultaneously, and
+ no ordering takes
+ place. </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>OnFailure=</varname></term>
+
+ <listitem><para>Lists one or more
+ units that are activated when this
+ unit enters the
+ '<literal>failed</literal>'
+ state.</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>
+ 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 will be stopped when it is
+ no longer used. Note that in order to
+ minimize the work to be executed,
+ systemd will not stop units by default
+ unless they are conflicting with other
+ units, or the user explicitly
+ requested their shut down. If this
+ option is set, a unit will be
+ automatically cleaned up if no other
+ active unit requires it. Defaults to
+ <option>false</option>.</para></listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><varname>RefuseManualStart=</varname></term>
+ <term><varname>RefuseManualStop=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ this unit can only be activated
+ (resp. deactivated) indirectly. In
+ this case explicit start-up
+ (resp. termination) requested by the
+ user is denied, however if it is
+ started (resp. stopped) as a
+ dependency of another unit, start-up
+ (resp. termination) will succeed. This
+ is mostly a safety feature to ensure
+ that the user does not accidentally
+ activate units that are not intended
+ to be activated explicitly, and not
+ accidentally deactivate units that are
+ not intended to be deactivated.
+ These options default to
+ <option>false</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>AllowIsolate=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ this unit may be used with the
+ <command>systemctl isolate</command>
+ command. Otherwise this will be
+ refused. It probably is a good idea to
+ leave this disabled except for target
+ units that shall be used similar to
+ runlevels in SysV init systems, just
+ as a precaution to avoid unusable
+ system states. This option defaults to
+ <option>false</option>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>DefaultDependencies=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ (the default), a few default
+ dependencies will implicitly be
+ created for the unit. The actual
+ dependencies created depend on the
+ unit type. For example, for service
+ units, these dependencies ensure that
+ the service is started only after
+ basic system initialization is
+ completed and is properly terminated on
+ system shutdown. See the respective
+ man pages for details. Generally, only
+ services involved with early boot or
+ late shutdown should set this option
+ to <option>false</option>. It is
+ highly recommended to leave this
+ option enabled for the majority of
+ common units. If set to
+ <option>false</option> this option
+ does not disable all implicit
+ dependencies, just non-essential
+ ones.</para></listitem>
+ </varlistentry>
+
<varlistentry>
- <term>Requires=</term>
- <listitem>
- <para>Dependencies on other
- units. If this units get
- activated the units listed
- here will be activated as
- well. If one of the other
- units gets deactivated or its
- activation fails, this unit
- will be deactivated. This
- option may be specified more
- than once.</para>
+ <term><varname>JobTimeoutSec=</varname></term>
+
+ <listitem><para>When clients are
+ waiting for a job of this unit to
+ complete, time out after the specified
+ time. If this time limit is reached
+ the job will be cancelled, the unit
+ however will not change state or even
+ enter the '<literal>failed</literal>'
+ mode. This value defaults to 0 (job
+ timeouts disabled), except for device
+ units. NB: this timeout is independent
+ from any unit-specific timeout (for
+ example, the timeout set with
+ <varname>Timeout=</varname> in service
+ units) as the job timeout has no
+ effect on the unit itself, only on the
+ job that might be pending for it. Or
+ in other words: unit-specific timeouts
+ are useful to abort unit state
+ changes, and revert them. The job
+ timeout set with this option however
+ is useful to abort only the job
+ waiting for the unit state to
+ change.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>ConditionPathExists=</varname></term>
+ <term><varname>ConditionPathExistsGlob=</varname></term>
+ <term><varname>ConditionPathIsDirectory=</varname></term>
+ <term><varname>ConditionDirectoryNotEmpty=</varname></term>
+ <term><varname>ConditionFileIsExecutable=</varname></term>
+ <term><varname>ConditionKernelCommandLine=</varname></term>
+ <term><varname>ConditionVirtualization=</varname></term>
+ <term><varname>ConditionSecurity=</varname></term>
+ <term><varname>ConditionNull=</varname></term>
+
+ <listitem><para>Before starting a unit
+ verify that the specified condition is
+ true. With
+ <varname>ConditionPathExists=</varname>
+ a file existence condition can be
+ 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
+ <varname>ConditionPathExists=</varname>
+ is prefixed with an exclamation mark
+ (!), the test is negated, and the unit
+ only started if the path does not
+ exist. <varname>ConditionPathExistsGlob=</varname>
+ work in a similar way, but checks for
+ the existance of at least one file or
+ directory matching the specified
+ globbing
+ pattern. <varname>ConditionPathIsDirectory=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a
+ directory. <varname>ConditionFileIsExecutable=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists, is a regular file and marked
+ executable.
+ <varname>ConditionDirectoryNotEmpty=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a non-empty
+ directory. Similarly
+ <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, separated
+ by the equality sign). 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. <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 virtual environment or one of the
+ <varname>qemu</varname>,
+ <varname>kvm</varname>,
+ <varname>vmware</varname>,
+ <varname>microsoft</varname>,
+ <varname>oracle</varname>,
+ <varname>xen</varname>,
+ <varname>pidns</varname>,
+ <varname>openvz</varname> to test
+ against a specific implementation. The
+ test may be negated by prepending an
+ exclamation mark.
+ <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. 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. 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.</para></listitem>
+ </varlistentry>
+
+ <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. Note
+ that in almost all cases this option
+ is not what you want. A symlink alias
+ in the file system is generally
+ preferable since it can be used as
+ lookup key. If a unit with a symlinked
+ alias name is not loaded and needs to
+ be it is easily found via the
+ symlink. However, if a unit with an
+ alias name configured with this
+ setting is not loaded it will not be
+ discovered. This settings' only use is
+ in conjunction with service
+ instances.</para>
</listitem>
</varlistentry>
</variablelist>
+
+ <para>Unit file may include a [Install] section, which
+ carries installation information for the unit. This
+ section is not interpreted by
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ during runtime. It is used exclusively by the
+ <command>enable</command> and
+ <command>disable</command> commands of the
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ tool during installation of a unit:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><varname>Alias=</varname></term>
+
+ <listitem><para>Additional names this
+ unit shall be installed under. 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. At installation
+ 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>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>WantedBy=</varname></term>
+
+ <listitem><para>Installs a symlink in
+ the <filename>.wants/</filename>
+ subdirectory for a unit. This has the
+ effect that when the listed unit name
+ is activated the unit listing it is
+ activated
+ too. <command>WantedBy=foo.service</command>
+ in a service
+ <filename>bar.service</filename> is
+ mostly equivalent to
+ <command>Alias=foo.service.wants/bar.service</command>
+ in the same file.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Also=</varname></term>
+
+ <listitem><para>Additional units to
+ install when this unit is
+ installed. If the user requests
+ installation of a unit with this
+ option configured,
+ <command>systemctl enable</command>
+ will automatically install units
+ listed in this option as
+ well.</para></listitem>
+ </varlistentry>
+ </variablelist>
+
</refsect1>
<refsect1>
- <title>See Also</title>
- <para>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>
- <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>
- </para>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <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>
</refsect1>
</refentry>
~ianmdlvl / elogind.git / blobdiff