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d24e1b4806
The virtualization condition and others use lowercase identifiers, so for the sake of keeping things least surprising, use lowercase identifiers here too.
798 lines
45 KiB
XML
798 lines
45 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!--
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This file is part of systemd.
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Copyright 2010 Lennart Poettering
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systemd is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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systemd is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with systemd; If not, see <http://www.gnu.org/licenses/>.
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-->
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<refentry id="systemd.unit">
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<refentryinfo>
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<title>systemd.unit</title>
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<productname>systemd</productname>
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<authorgroup>
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<author>
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<contrib>Developer</contrib>
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<firstname>Lennart</firstname>
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<surname>Poettering</surname>
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<email>lennart@poettering.net</email>
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</author>
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</authorgroup>
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</refentryinfo>
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<refmeta>
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<refentrytitle>systemd.unit</refentrytitle>
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<manvolnum>5</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>systemd.unit</refname>
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<refpurpose>systemd unit configuration files</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<para><filename>systemd.service</filename>,
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<filename>systemd.socket</filename>,
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<filename>systemd.device</filename>,
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<filename>systemd.mount</filename>,
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<filename>systemd.automount</filename>,
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<filename>systemd.swap</filename>,
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<filename>systemd.target</filename>,
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<filename>systemd.path</filename>,
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<filename>systemd.timer</filename>,
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<filename>systemd.snapshot</filename></para>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para>A unit configuration file encodes information
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about a service, a socket, a device, a mount point, an
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automount point, a swap file or partition, a start-up
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target, a file system path or a timer controlled and
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supervised by
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<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The
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syntax is inspired by <ulink
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url="http://standards.freedesktop.org/desktop-entry-spec/latest/">XDG
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Desktop Entry Specification</ulink> <filename>.desktop</filename> files, which are in turn
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inspired by Microsoft Windows
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<filename>.ini</filename> files.</para>
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<para>This man pages lists the common configuration
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options of all the unit types. These options need to
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be configured in the [Unit] resp. [Install]
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section of the unit files.</para>
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<para>In addition to the generic [Unit] and [Install]
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sections described here, each unit should have a
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type-specific section, e.g. [Service] for a service
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unit. See the respective man pages for more
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information.</para>
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<para>Unit files may contain additional options on top
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of those listed here. If systemd encounters an unknown
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option it will write a warning log message but
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continue loading the unit. If an option is prefixed
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with <option>X-</option> it is ignored completely by
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systemd. Applications may use this to include
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additional information in the unit files.</para>
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<para>Boolean arguments used in unit files can be
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written in various formats. For positive settings the
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strings <option>1</option>, <option>yes</option>,
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<option>true</option> and <option>on</option> are
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equivalent. For negative settings the strings
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<option>0</option>, <option>no</option>,
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<option>false</option> and <option>off</option> are
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equivalent.</para>
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<para>Time span values encoded in unit files can be
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written in various formats. A stand-alone number
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specifies a time in seconds. If suffixed with a time
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unit, the unit is honored. A concatenation of
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multiple values with units is supported, in which case
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the values are added up. Example: "50" refers to 50
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seconds; "2min 200ms" refers to 2 minutes plus 200
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milliseconds, i.e. 120200ms. The following time units
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are understood: s, min, h, d, w, ms, us.</para>
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<para>Empty lines and lines starting with # or ; are
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ignored. This may be used for commenting. Lines ending
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in a backslash are concatenated with the following
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line while reading and the backslash is replaced by a
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space character. This may be used to wrap long lines.</para>
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<para>If a line starts with <option>.include</option>
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followed by a file name, the specified file will be
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read as if its contents were listed in place of the
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<option>.include</option> directive.</para>
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<para>Along with a unit file
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<filename>foo.service</filename> a directory
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<filename>foo.service.wants/</filename> may exist. All
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units symlinked from such a directory are implicitly
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added as dependencies of type
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<varname>Wanted=</varname> to the unit. This is useful
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to hook units into the start-up of other units,
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without having to modify their unit configuration
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files. For details about the semantics of
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<varname>Wanted=</varname> see below. The preferred
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way to create symlinks in the
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<filename>.wants/</filename> directory of a service is
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with the <command>enable</command> command of the
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<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
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tool which reads information from the [Install]
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section of unit files. (See below.) A similar
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functionality exists for <varname>Requires=</varname>
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type dependencies as well, the directory suffix is
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<filename>.requires/</filename> in this case.</para>
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<para>Note that while systemd offers a flexible
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dependency system between units it is recommended to
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use this functionality only sparsely and instead rely
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on techniques such as bus-based or socket-based
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activation which makes dependencies implicit, which
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both results in a simpler and more flexible
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system.</para>
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<para>Some unit names reflect paths existing in the
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file system name space. Example: a device unit
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<filename>dev-sda.device</filename> refers to a device
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with the device node <filename>/dev/sda</filename> in
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the file system namespace. If this applies a special
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way to escape the path name is used, so that the
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result is usable as part of a file name. Basically,
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given a path, "/" is replaced by "-", and all
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unprintable characters and the "-" are replaced by
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C-style "\x20" escapes. The root directory "/" is
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encoded as single dash, while otherwise the initial
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and ending "/" is removed from all paths during
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transformation. This escaping is reversible.</para>
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<para>Optionally, units may be instantiated from a
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template file at runtime. This allows creation of
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multiple units from a single configuration file. If
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systemd looks for a unit configuration file it will
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first search for the literal unit name in the
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filesystem. If that yields no success and the unit
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name contains an @ character, systemd will look for a
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unit template that shares the same name but with the
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instance string (i.e. the part between the @ character
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and the suffix) removed. Example: if a service
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<filename>getty@tty3.service</filename> is requested
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and no file by that name is found, systemd will look
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for <filename>getty@.service</filename> and
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instantiate a service from that configuration file if
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it is found. To refer to the instance string from
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within the configuration file you may use the special
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<literal>%i</literal> specifier in many of the
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configuration options. Other specifiers that may be
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used are <literal>%n</literal>, <literal>%N</literal>,
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<literal>%p</literal>, <literal>%P</literal>,
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<literal>%I</literal> and <literal>%f</literal>, for
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the full unit name, the unescaped unit name, the
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prefix name, the unescaped prefix name, the unescaped
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instance name and the unescaped filename,
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respectively. The unescaped filename is either the
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unescaped instance name (if set) with / prepended (if
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necessary), or the prefix name similarly prepended
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with /. The prefix name here refers to the string
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before the @, i.e. "getty" in the example above, where
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"tty3" is the instance name.</para>
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<para>If a unit file is empty (i.e. has the file size
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0) or is symlinked to <filename>/dev/null</filename>
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its configuration will not be loaded and it appears
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with a load state of <literal>masked</literal>, and
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cannot be activated. Use this as an effective way to
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fully disable a unit, making it impossible to start it
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even manually.</para>
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<para>The unit file format is covered by the
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<ulink
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url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
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Stability Promise</ulink>.</para>
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</refsect1>
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<refsect1>
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<title>Options</title>
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<para>Unit file may include a [Unit] section, which
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carries generic information about the unit that is not
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dependent on the type of unit:</para>
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<variablelist>
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<varlistentry>
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<term><varname>Description=</varname></term>
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<listitem><para>A free-form string
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describing the unit. This is intended
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for use in UIs to show descriptive
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information along with the unit
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name.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>Requires=</varname></term>
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<listitem><para>Configures requirement
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dependencies on other units. If this
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unit gets activated, the units listed
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here will be activated as well. If one
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of the other units gets deactivated or
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its activation fails, this unit will
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be deactivated. This option may be
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specified more than once, in which
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case requirement dependencies for all
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listed names are created. Note that
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requirement dependencies do not
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influence the order in which services
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are started or stopped. This has to be
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configured independently with the
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<varname>After=</varname> or
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<varname>Before=</varname> options. If
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a unit
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<filename>foo.service</filename>
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requires a unit
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<filename>bar.service</filename> as
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configured with
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<varname>Requires=</varname> and no
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ordering is configured with
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<varname>After=</varname> or
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<varname>Before=</varname>, then both
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units will be started simultaneously
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and without any delay between them if
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<filename>foo.service</filename> is
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activated. Often it is a better choice
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to use <varname>Wants=</varname>
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instead of
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<varname>Requires=</varname> in order
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to achieve a system that is more
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robust when dealing with failing
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services.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>RequiresOverridable=</varname></term>
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<listitem><para>Similar to
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<varname>Requires=</varname>.
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Dependencies listed in
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<varname>RequiresOverridable=</varname>
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which cannot be fulfilled or fail to
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start are ignored if the startup was
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explicitly requested by the user. If
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the start-up was pulled in indirectly
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by some dependency or automatic
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start-up of units that is not
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requested by the user this dependency
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must be fulfilled and otherwise the
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transaction fails. Hence, this option
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may be used to configure dependencies
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that are normally honored unless the
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user explicitly starts up the unit, in
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which case whether they failed or not
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is irrelevant.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>Requisite=</varname></term>
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<term><varname>RequisiteOverridable=</varname></term>
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<listitem><para>Similar to
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<varname>Requires=</varname>
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resp. <varname>RequiresOverridable=</varname>. However,
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if a unit listed here is not started
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already it will not be started and the
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transaction fails
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immediately.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>Wants=</varname></term>
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<listitem><para>A weaker version of
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<varname>Requires=</varname>. A unit
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listed in this option will be started
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if the configuring unit is. However,
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if the listed unit fails to start up
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or cannot be added to the transaction
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this has no impact on the validity of
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the transaction as a whole. This is
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the recommended way to hook start-up
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of one unit to the start-up of another
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unit. Note that dependencies of this
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type may also be configured outside of
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the unit configuration file by
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adding a symlink to a
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<filename>.wants/</filename> directory
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accompanying the unit file. For
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details see above.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>BindTo=</varname></term>
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<listitem><para>Configures requirement
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dependencies, very similar in style to
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<varname>Requires=</varname>, however
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in addition to this behaviour it also
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declares that this unit is stopped
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when any of the units listed suddenly
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disappears. Units can suddenly,
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unexpectedly disappear if a service
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terminates on its own choice, a device
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is unplugged or a mount point
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unmounted without involvement of
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systemd.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>Conflicts=</varname></term>
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<listitem><para>Configures negative
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requirement dependencies. If a unit
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has a
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<varname>Conflicts=</varname> setting
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on another unit, starting the former
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will stop the latter and vice
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versa. Note that this setting is
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independent of and orthogonal to the
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<varname>After=</varname> and
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<varname>Before=</varname> ordering
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dependencies.</para>
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<para>If a unit A that conflicts with
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a unit B is scheduled to be started at
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the same time as B, the transaction
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will either fail (in case both are
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required part of the transaction) or
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be modified to be fixed (in case one
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or both jobs are not a required part
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of the transaction). In the latter
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case the job that is not the required
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will be removed, or in case both are
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not required the unit that conflicts
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will be started and the unit that is
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conflicted is
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stopped.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>Before=</varname></term>
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<term><varname>After=</varname></term>
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<listitem><para>Configures ordering
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dependencies between units. If a unit
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<filename>foo.service</filename>
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contains a setting
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<option>Before=bar.service</option>
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and both units are being started,
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<filename>bar.service</filename>'s
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start-up is delayed until
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<filename>foo.service</filename> is
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started up. Note that this setting is
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independent of and orthogonal to the
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requirement dependencies as configured
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by <varname>Requires=</varname>. It is
|
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a common pattern to include a unit
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name in both the
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<varname>After=</varname> and
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<varname>Requires=</varname> option in
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which case the unit listed will be
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started before the unit that is
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configured with these options. This
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option may be specified more than
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once, in which case ordering
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dependencies for all listed names are
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created. <varname>After=</varname> is
|
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the inverse of
|
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<varname>Before=</varname>, i.e. while
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<varname>After=</varname> ensures that
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the configured unit is started after
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the listed unit finished starting up,
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<varname>Before=</varname> ensures the
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opposite, i.e. that the configured
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unit is fully started up before the
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listed unit is started. Note that when
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two units with an ordering dependency
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between them are shut down, the
|
|
inverse of the start-up order is
|
|
applied. i.e. if a unit is configured
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with <varname>After=</varname> on
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another unit, the former is stopped
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before the latter if both are shut
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down. If one unit with an ordering
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dependency on another unit is shut
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|
down while the latter is started up,
|
|
the shut down is ordered before the
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|
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
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no ordering takes
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place. </para></listitem>
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</varlistentry>
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|
|
<varlistentry>
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|
<term><varname>OnFailure=</varname></term>
|
|
|
|
<listitem><para>Lists one or more
|
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units that are activated when this
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|
unit enters the
|
|
'<literal>failed</literal>'
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|
state.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
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|
<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>
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|
this unit can only be activated
|
|
(resp. deactivated) indirectly. In
|
|
this case explicit start-up
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|
(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
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|
<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><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>ConditionPathIsDirectory=</varname></term>
|
|
<term><varname>ConditionDirectoryNotEmpty=</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 existance 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>ConditionPathIsDirectory=</varname>
|
|
is similar to
|
|
<varname>ConditionPathExists=</varname>
|
|
but verifies whether a certain path
|
|
exists and is a directory.
|
|
<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>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>
|