mirror of
https://github.com/systemd/systemd.git
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6baf995c17
So far the compatibility with .desktop settings hasn't been imporant at all, and we do not want people to write convoluted unit files.
1054 lines
61 KiB
XML
1054 lines
61 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
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<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
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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 Lesser General Public License as published by
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the Free Software Foundation; either version 2.1 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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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser 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.service">
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<refentryinfo>
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<title>systemd.service</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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|
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<refmeta>
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<refentrytitle>systemd.service</refentrytitle>
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<manvolnum>5</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>systemd.service</refname>
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<refpurpose>Service unit configuration</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<para><filename><replaceable>service</replaceable>.service</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 whose name ends in
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<filename>.service</filename> encodes information
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about a process controlled and supervised by
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systemd.</para>
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<para>This man page lists the configuration options
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specific to this unit type. See
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<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
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for the common options of all unit configuration
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files. The common configuration items are configured
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in the generic <literal>[Unit]</literal> and
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<literal>[Install]</literal> sections. The service
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specific configuration options are configured in the
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<literal>[Service]</literal> section.</para>
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<para>Additional options are listed in
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<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
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which define the execution environment the commands
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are executed in, and in
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<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
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which define the way the processes of the service are
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terminated, and in
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<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
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which configure resource control settings for the
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processes of the service.</para>
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<para>Unless <varname>DefaultDependencies=</varname>
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is set to <option>false</option>, service units will
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implicitly have dependencies of type
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<varname>Requires=</varname> and
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<varname>After=</varname> on
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<filename>basic.target</filename> as well as
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dependencies of type <varname>Conflicts=</varname> and
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<varname>Before=</varname> on
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<filename>shutdown.target</filename>. These ensure
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that normal service units pull in basic system
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initialization, and are terminated cleanly prior to
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system shutdown. Only services involved with early
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boot or late system shutdown should disable this
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option.</para>
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<para>If a service is requested under a certain name
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but no unit configuration file is found, systemd looks
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for a SysV init script by the same name (with the
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<filename>.service</filename> suffix removed) and
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dynamically creates a service unit from that
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script. This is useful for compatibility with
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SysV. Note that this compatibility is quite
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comprehensive but not 100%. For details about the
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incompatibilities see the <ulink
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url="http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
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with SysV</ulink> document.
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</para>
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</refsect1>
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<refsect1>
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<title>Options</title>
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<para>Service files must include a
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<literal>[Service]</literal> section, which carries
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information about the service and the process it
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supervises. A number of options that may be used in
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this section are shared with other unit types. These
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options are documented in
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<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
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and
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<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
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options specific to the <literal>[Service]</literal>
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section of service units are the following:</para>
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<variablelist class='unit-directives'>
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<varlistentry>
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<term><varname>Type=</varname></term>
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<listitem><para>Configures the process
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start-up type for this service
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unit. One of <option>simple</option>,
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<option>forking</option>,
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<option>oneshot</option>,
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<option>dbus</option>,
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<option>notify</option> or
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<option>idle</option>.</para>
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<para>If set to
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<option>simple</option> (the default
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value if <varname>BusName=</varname>
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is not specified), it is expected that
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the process configured with
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<varname>ExecStart=</varname> is the
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main process of the service. In this
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mode, if the process offers
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functionality to other processes on
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the system, its communication channels
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should be installed before the daemon
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is started up (e.g. sockets set up by
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systemd, via socket activation), as
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systemd will immediately proceed
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starting follow-up units.</para>
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<para>If set to
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<option>forking</option>, it is
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expected that the process configured
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with <varname>ExecStart=</varname>
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will call <function>fork()</function>
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as part of its start-up. The parent process is
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expected to exit when start-up is
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complete and all communication
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channels are set up. The child continues
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to run as the main daemon
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process. This is the behavior of
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traditional UNIX daemons. If this
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setting is used, it is recommended to
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also use the
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<varname>PIDFile=</varname> option, so
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that systemd can identify the main
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process of the daemon. systemd will
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proceed starting follow-up units as
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soon as the parent process
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exits.</para>
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<para>Behavior of
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<option>oneshot</option> is similar
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to <option>simple</option>, however
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it is expected that the process has to
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exit before systemd starts follow-up
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units. <varname>RemainAfterExit=</varname>
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is particularly useful for this type
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of service.</para>
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<para>Behavior of
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<option>dbus</option> is similar to
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<option>simple</option>, however it is
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expected that the daemon acquires a
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name on the D-Bus bus, as configured
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by
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<varname>BusName=</varname>. systemd
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will proceed starting follow-up units
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after the D-Bus bus name has been
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acquired. Service units with this
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option configured implicitly gain
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dependencies on the
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<filename>dbus.socket</filename>
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unit. This type is the default if
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<varname>BusName=</varname> is
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specified.</para>
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<para>Behavior of
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<option>notify</option> is similar to
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<option>simple</option>, however it is
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expected that the daemon sends a
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notification message via
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<citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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or an equivalent call when it finished
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starting up. systemd will proceed
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starting follow-up units after this
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notification message has been sent. If
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this option is used,
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<varname>NotifyAccess=</varname> (see
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below) should be set to open access to
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the notification socket provided by
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systemd. If
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<varname>NotifyAccess=</varname> is
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not set, it will be implicitly set to
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<option>main</option>. Note that
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currently
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<varname>Type=</varname><option>notify</option>
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will not work if used in combination with
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<varname>PrivateNetwork=</varname><option>yes</option>.</para>
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<para>Behavior of
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<option>idle</option> is very similar
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to <option>simple</option>, however
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actual execution of the service
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binary is delayed until all jobs are
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dispatched. This may be used to avoid
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interleaving of output of shell
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services with the status output on the
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console.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><varname>RemainAfterExit=</varname></term>
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<listitem><para>Takes a boolean value
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that specifies whether the service
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shall be considered active even when
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all its processes exited. Defaults to
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<option>no</option>.</para>
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</listitem>
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</varlistentry>
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|
<varlistentry>
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<term><varname>GuessMainPID=</varname></term>
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<listitem><para>Takes a boolean value
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that specifies whether systemd should
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|
try to guess the main PID of a service
|
|
if it cannot be determined
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|
reliably. This option is ignored
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|
unless <option>Type=forking</option>
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|
is set and <option>PIDFile=</option>
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|
is unset because for the other types
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|
or with an explicitly configured PID
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file the main PID is always known. The
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|
guessing algorithm might come to
|
|
incorrect conclusions if a daemon
|
|
consists of more than one process. If
|
|
the main PID cannot be determined,
|
|
failure detection and automatic
|
|
restarting of a service will not work
|
|
reliably. Defaults to
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|
<option>yes</option>.</para>
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|
</listitem>
|
|
</varlistentry>
|
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|
<varlistentry>
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<term><varname>PIDFile=</varname></term>
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<listitem><para>Takes an absolute file
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name pointing to the PID file of this
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daemon. Use of this option is
|
|
recommended for services where
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<varname>Type=</varname> is set to
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<option>forking</option>. systemd will
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read the PID of the main process of
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the daemon after start-up of the
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service. systemd will not write to the
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file configured here.</para>
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</listitem>
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</varlistentry>
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|
<varlistentry>
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|
<term><varname>BusName=</varname></term>
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<listitem><para>Takes a D-Bus bus
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name, that this service is reachable
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as. This option is mandatory for
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services where
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<varname>Type=</varname> is set to
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|
<option>dbus</option>, but its use
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is otherwise recommended as well if
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the process takes a name on the D-Bus
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|
bus.</para>
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</listitem>
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</varlistentry>
|
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<varlistentry>
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<term><varname>ExecStart=</varname></term>
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<listitem><para>Commands with their
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arguments that are executed when this
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service is started. For each of the
|
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specified commands, the first argument
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must be an absolute and literal path
|
|
to an executable.</para>
|
|
|
|
<para>When <varname>Type</varname> is
|
|
not <option>oneshot</option>, only one
|
|
command may be given. When
|
|
<varname>Type=oneshot</varname> is
|
|
used, more than one command may be
|
|
specified. Multiple command lines may
|
|
be concatenated in a single directive,
|
|
by separating them with semicolons
|
|
(these semicolons must be passed as
|
|
separate words). Alternatively, this
|
|
directive may be specified more than
|
|
once with the same effect.
|
|
Lone semicolons may be escaped as
|
|
<literal>\;</literal>. If the empty
|
|
string is assigned to this option, the
|
|
list of commands to start is reset,
|
|
prior assignments of this option will
|
|
have no effect.</para>
|
|
|
|
<para>Each command line is split on
|
|
whitespace, with the first item being
|
|
the command to execute, and the
|
|
subsequent items being the arguments.
|
|
Double quotes ("...") and single
|
|
quotes ('...') may be used, in which
|
|
case everything until the next
|
|
matching quote becomes part of the
|
|
same argument. Quotes themselves are
|
|
removed after parsing. In addition, a
|
|
trailing backslash
|
|
(<literal>\</literal>) may be used to
|
|
merge lines. This syntax is intended
|
|
to be very similar to shell syntax,
|
|
but only the meta-characters and
|
|
expansions described in the following
|
|
paragraphs are understood.
|
|
Specifically, redirection using
|
|
<literal><</literal>,
|
|
<literal><<</literal>,
|
|
<literal>></literal>, and
|
|
<literal>>></literal>, pipes
|
|
using <literal>|</literal>, and
|
|
running programs in the background
|
|
using <literal>&</literal>
|
|
and <emphasis>other elements of shell
|
|
syntax are not supported</emphasis>.
|
|
</para>
|
|
|
|
<para>If more than one command is
|
|
specified, the commands are invoked
|
|
one by one sequentially in the order
|
|
they appear in the unit file. If one
|
|
of the commands fails (and is not
|
|
prefixed with <literal>-</literal>),
|
|
other lines are not executed and the
|
|
unit is considered failed.</para>
|
|
|
|
<para>Unless
|
|
<varname>Type=forking</varname> is
|
|
set, the process started via this
|
|
command line will be considered the
|
|
main process of the daemon.</para>
|
|
|
|
<para>The command line accepts
|
|
<literal>%</literal> specifiers as
|
|
described in
|
|
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
|
|
Note that the first argument of the
|
|
command line (i.e. the program to
|
|
execute) may not include
|
|
specifiers.</para>
|
|
|
|
<para>Basic environment variable
|
|
substitution is supported. Use
|
|
<literal>${FOO}</literal> as part of a
|
|
word, or as a word of its own on the
|
|
command line, in which case it will be
|
|
replaced by the value of the
|
|
environment variable including all
|
|
whitespace it contains, resulting in a
|
|
single argument. Use
|
|
<literal>$FOO</literal> as a separate
|
|
word on the command line, in which
|
|
case it will be replaced by the value
|
|
of the environment variable split up
|
|
at whitespace, resulting in zero or
|
|
more arguments. To pass a literal dollar sign,
|
|
use <literal>$$</literal>. Note that the first
|
|
argument (i.e. the program to execute)
|
|
may not be a variable.</para>
|
|
|
|
<para>Optionally, if the absolute file
|
|
name is prefixed with
|
|
<literal>@</literal>, the second token
|
|
will be passed as
|
|
<literal>argv[0]</literal> to the
|
|
executed process, followed by the
|
|
further arguments specified. If the
|
|
absolute filename is prefixed with
|
|
<literal>-</literal>, an exit code of
|
|
the command normally considered a
|
|
failure (i.e. non-zero exit status or
|
|
abnormal exit due to signal) is ignored
|
|
and considered success. If both
|
|
<literal>-</literal> and
|
|
<literal>@</literal> are used, they
|
|
can appear in either order.</para>
|
|
|
|
<para>Note that this setting does not
|
|
directly support shell command
|
|
lines. If shell command lines are to
|
|
be used, they need to be passed
|
|
explicitly to a shell implementation
|
|
of some kind. Example:</para>
|
|
<programlisting>ExecStart=/bin/sh -c 'dmesg | tac'
|
|
</programlisting>
|
|
|
|
<para>Only select environment variables
|
|
are set for executed commands. See
|
|
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
|
|
</para>
|
|
|
|
<para>Example:</para>
|
|
<programlisting>ExecStart=/bin/echo one ; /bin/echo "two two"
|
|
</programlisting>
|
|
<para>This will execute
|
|
<command>/bin/echo</command> two
|
|
times, each time with one argument,
|
|
<literal>one</literal> and
|
|
<literal>two two</literal>,
|
|
respectively. Since two commands are
|
|
specified
|
|
<varname>Type=oneshot</varname> must
|
|
be used.</para>
|
|
|
|
<para>Example:</para>
|
|
<programlisting>ExecStart=/bin/echo / >/dev/null & \; \
|
|
/bin/ls
|
|
</programlisting>
|
|
<para>This will execute
|
|
<command>/bin/echo</command> with five
|
|
arguments: <literal>/</literal>,
|
|
<literal>>/dev/null</literal>,
|
|
<literal>&</literal>,
|
|
<literal>;</literal>, and
|
|
<literal>/bin/ls</literal>.</para>
|
|
|
|
<para>Example:</para>
|
|
<programlisting>Environment="ONE=one" 'TWO=two two'
|
|
ExecStart=/bin/echo $ONE $TWO ${TWO}
|
|
</programlisting>
|
|
<para>This will execute
|
|
<command>/bin/echo</command> with four
|
|
arguments: <literal>one</literal>,
|
|
<literal>two</literal>,
|
|
<literal>two</literal>, and
|
|
<literal>two two</literal>.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>ExecStartPre=</varname></term>
|
|
<term><varname>ExecStartPost=</varname></term>
|
|
<listitem><para>Additional commands
|
|
that are executed before or after
|
|
the command in
|
|
<varname>ExecStart=</varname>, respectively.
|
|
Syntax is the same as for
|
|
<varname>ExecStart=</varname>, except
|
|
that multiple command lines are allowed
|
|
and the commands are executed one
|
|
after the other, serially.</para>
|
|
|
|
<para>If any of those commands (not
|
|
prefixed with <literal>-</literal>)
|
|
fail, the rest are not executed and
|
|
the unit is considered failed.</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>ExecReload=</varname></term>
|
|
<listitem><para>Commands to execute to
|
|
trigger a configuration reload in the
|
|
service. This argument takes multiple
|
|
command lines, following the same
|
|
scheme as described for
|
|
<varname>ExecStart=</varname>
|
|
above. Use of this setting is
|
|
optional. Specifier and environment
|
|
variable substitution is supported
|
|
here following the same scheme as for
|
|
<varname>ExecStart=</varname>.</para>
|
|
|
|
<para>One additional special
|
|
environment variables is set: if known
|
|
<varname>$MAINPID</varname> is set to
|
|
the main process of the daemon, and
|
|
may be used for command lines like the
|
|
following:</para>
|
|
|
|
<programlisting>/bin/kill -HUP $MAINPID</programlisting>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>ExecStop=</varname></term>
|
|
<listitem><para>Commands to execute to
|
|
stop the service started via
|
|
<varname>ExecStart=</varname>. This
|
|
argument takes multiple command lines,
|
|
following the same scheme as described
|
|
for <varname>ExecStart=</varname>
|
|
above. Use of this setting is
|
|
optional. All processes remaining for
|
|
a service after the commands
|
|
configured in this option are run are
|
|
terminated according to the
|
|
<varname>KillMode=</varname> setting
|
|
(see
|
|
<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
|
|
this option is not specified, the
|
|
process is terminated right-away when
|
|
service stop is requested. Specifier
|
|
and environment variable substitution
|
|
is supported (including
|
|
<varname>$MAINPID</varname>, see
|
|
above).</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>ExecStopPost=</varname></term>
|
|
<listitem><para>Additional commands
|
|
that are executed after the service
|
|
was stopped. This includes cases where
|
|
the commands configured in
|
|
<varname>ExecStop=</varname> were used,
|
|
where the service does not have any
|
|
<varname>ExecStop=</varname> defined, or
|
|
where the service exited unexpectedly. This
|
|
argument takes multiple command lines,
|
|
following the same scheme as described
|
|
for <varname>ExecStart</varname>. Use
|
|
of these settings is
|
|
optional. Specifier and environment
|
|
variable substitution is
|
|
supported.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>RestartSec=</varname></term>
|
|
<listitem><para>Configures the time to
|
|
sleep before restarting a service (as
|
|
configured with
|
|
<varname>Restart=</varname>). Takes a
|
|
unit-less value in seconds, or a time
|
|
span value such as "5min
|
|
20s". Defaults to
|
|
100ms.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>TimeoutStartSec=</varname></term>
|
|
<listitem><para>Configures the time to
|
|
wait for start-up. If a
|
|
daemon service does not signal
|
|
start-up completion within the
|
|
configured time, the service will be
|
|
considered failed and be shut down
|
|
again.
|
|
Takes a unit-less value in seconds, or a
|
|
time span value such as "5min
|
|
20s". Pass 0 to disable the timeout
|
|
logic. Defaults to <varname>TimeoutStartSec=</varname> from the
|
|
manager configuration file, except when
|
|
<varname>Type=oneshot</varname> is
|
|
used, in which case the timeout
|
|
is disabled by default.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>TimeoutStopSec=</varname></term>
|
|
<listitem><para>Configures the time to
|
|
wait for stop. If a service is asked
|
|
to stop but does not terminate in the
|
|
specified time, it will be terminated
|
|
forcibly via <constant>SIGTERM</constant>, and after
|
|
another delay of this time with
|
|
<constant>SIGKILL</constant> (See
|
|
<varname>KillMode=</varname>
|
|
in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
|
|
Takes a unit-less value in seconds, or a
|
|
time span value such as "5min
|
|
20s". Pass 0 to disable the timeout
|
|
logic. Defaults to <varname>TimeoutStartSec=</varname> from the
|
|
manager configuration file.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>TimeoutSec=</varname></term>
|
|
<listitem><para>A shorthand for configuring
|
|
both <varname>TimeoutStartSec=</varname>
|
|
and <varname>TimeoutStopSec=</varname>
|
|
to the specified value.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>WatchdogSec=</varname></term>
|
|
<listitem><para>Configures the
|
|
watchdog timeout for a service. The
|
|
watchdog is activated when the start-up is
|
|
completed. The service must call
|
|
<citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
regularly with "WATCHDOG=1" (i.e. the
|
|
"keep-alive ping"). If the time
|
|
between two such calls is larger than
|
|
the configured time, then the service
|
|
is placed in a failure state. By
|
|
setting <varname>Restart=</varname> to
|
|
<option>on-failure</option> or
|
|
<option>always</option>, the service
|
|
will be automatically restarted. The
|
|
time configured here will be passed to
|
|
the executed service process in the
|
|
<varname>WATCHDOG_USEC=</varname>
|
|
environment variable. This allows
|
|
daemons to automatically enable the
|
|
keep-alive pinging logic if watchdog
|
|
support is enabled for the service. If
|
|
this option is used,
|
|
<varname>NotifyAccess=</varname> (see
|
|
below) should be set to open access to
|
|
the notification socket provided by
|
|
systemd. If
|
|
<varname>NotifyAccess=</varname> is
|
|
not set, it will be implicitly set to
|
|
<option>main</option>. Defaults to 0,
|
|
which disables this
|
|
feature.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>Restart=</varname></term>
|
|
<listitem><para>Configures whether the
|
|
service shall be restarted when the
|
|
service process exits, is killed,
|
|
or a timeout is reached. The service
|
|
process may be the main service
|
|
process, but also one of the processes
|
|
specified with
|
|
<varname>ExecStartPre=</varname>,
|
|
<varname>ExecStartPost=</varname>,
|
|
<varname>ExecStopPre=</varname>,
|
|
<varname>ExecStopPost=</varname>, or
|
|
<varname>ExecReload=</varname>.
|
|
When the death of the process is a
|
|
result of systemd operation (e.g. service
|
|
stop or restart), the service will not be
|
|
restarted. Timeouts include missing
|
|
the watchdog "keep-alive ping"
|
|
deadline and a service start, reload,
|
|
and stop operation timeouts.</para>
|
|
|
|
<para>Takes one of
|
|
<option>no</option>,
|
|
<option>on-success</option>,
|
|
<option>on-failure</option>,
|
|
<option>on-watchdog</option>,
|
|
<option>on-abort</option>, or
|
|
<option>always</option>. If set to
|
|
<option>no</option> (the default), the
|
|
service will not be restarted. If set to
|
|
<option>on-success</option>, it will be
|
|
restarted only when the service process
|
|
exits cleanly.
|
|
In this context, a clean exit means
|
|
an exit code of 0, or one of the signals
|
|
<constant>SIGHUP</constant>, <constant>SIGINT</constant>, <constant>SIGTERM</constant>, or <constant>SIGPIPE</constant>, and
|
|
additionally, exit statuses and signals
|
|
specified in <varname>SuccessExitStatus=</varname>.
|
|
If set to <option>on-failure</option>,
|
|
the service will be restarted when the
|
|
process exits with an nonzero exit code,
|
|
is terminated by a signal (including on
|
|
core dump), when an operation (such as
|
|
service reload) times out, and when the
|
|
configured watchdog timeout is triggered.
|
|
If set to
|
|
<option>on-abort</option>, the service
|
|
will be restarted only if the service
|
|
process exits due to an uncaught
|
|
signal not specified as a clean exit
|
|
status.
|
|
If set to
|
|
<option>on-watchdog</option>, the service
|
|
will be restarted only if the watchdog
|
|
timeout for the service expires.
|
|
If set to
|
|
<option>always</option>, the service
|
|
will be restarted regardless whether
|
|
it exited cleanly or not, got
|
|
terminated abnormally by a signal or
|
|
hit a timeout.</para>
|
|
|
|
<para>In addition to the above settings,
|
|
the service will not be restarted if the
|
|
exit code or signal is specified in
|
|
<varname>RestartPreventExitStatus=</varname>
|
|
(see below).</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>SuccessExitStatus=</varname></term>
|
|
<listitem><para>Takes a list of exit
|
|
status definitions that when returned
|
|
by the main service process will be
|
|
considered successful termination, in
|
|
addition to the normal successful exit
|
|
code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
|
|
<constant>SIGTERM</constant> and <constant>SIGPIPE</constant>. Exit status
|
|
definitions can either be numeric exit
|
|
codes or termination signal names,
|
|
separated by spaces. Example:
|
|
<literal>SuccessExitStatus=1 2 8
|
|
<constant>SIGKILL</constant></literal>, ensures that exit
|
|
codes 1, 2, 8 and the termination
|
|
signal <constant>SIGKILL</constant> are considered clean
|
|
service terminations. This option may
|
|
appear more than once in which case
|
|
the list of successful exit statuses
|
|
is merged. If the empty string is
|
|
assigned to this option, the list is
|
|
reset, all prior assignments of this
|
|
option will have no
|
|
effect.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>RestartPreventExitStatus=</varname></term>
|
|
<listitem><para>Takes a list of exit
|
|
status definitions that when returned
|
|
by the main service process will
|
|
prevent automatic service restarts
|
|
regardless of the restart setting
|
|
configured with
|
|
<varname>Restart=</varname>. Exit
|
|
status definitions can either be
|
|
numeric exit codes or termination
|
|
signal names, and are separated by
|
|
spaces. Defaults to the empty list, so
|
|
that by default no exit status is
|
|
excluded from the configured restart
|
|
logic. Example:
|
|
<literal>RestartPreventExitStatus=1 6
|
|
SIGABRT</literal>, ensures that exit
|
|
codes 1 and 6 and the termination
|
|
signal SIGABRT will not result in
|
|
automatic service restarting. This
|
|
option may appear more than once in
|
|
which case the list of restart preventing
|
|
statuses is merged. If the empty
|
|
string is assigned to this option, the
|
|
list is reset, all prior assignments
|
|
of this option will have no
|
|
effect.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>PermissionsStartOnly=</varname></term>
|
|
<listitem><para>Takes a boolean
|
|
argument. If true, the permission
|
|
related execution options as
|
|
configured with
|
|
<varname>User=</varname> and similar
|
|
options (see
|
|
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
|
for more information) are only applied
|
|
to the process started with
|
|
<varname>ExecStart=</varname>, and not
|
|
to the various other
|
|
<varname>ExecStartPre=</varname>,
|
|
<varname>ExecStartPost=</varname>,
|
|
<varname>ExecReload=</varname>,
|
|
<varname>ExecStop=</varname>,
|
|
<varname>ExecStopPost=</varname>
|
|
commands. If false, the setting is
|
|
applied to all configured commands the
|
|
same way. Defaults to
|
|
false.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>RootDirectoryStartOnly=</varname></term>
|
|
<listitem><para>Takes a boolean
|
|
argument. If true, the root directory
|
|
as configured with the
|
|
<varname>RootDirectory=</varname>
|
|
option (see
|
|
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
|
for more information) is only applied
|
|
to the process started with
|
|
<varname>ExecStart=</varname>, and not
|
|
to the various other
|
|
<varname>ExecStartPre=</varname>,
|
|
<varname>ExecStartPost=</varname>,
|
|
<varname>ExecReload=</varname>,
|
|
<varname>ExecStop=</varname>,
|
|
<varname>ExecStopPost=</varname>
|
|
commands. If false, the setting is
|
|
applied to all configured commands the
|
|
same way. Defaults to
|
|
false.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>NonBlocking=</varname></term>
|
|
<listitem><para>Set O_NONBLOCK flag
|
|
for all file descriptors passed via
|
|
socket-based activation. If true, all
|
|
file descriptors >= 3 (i.e. all except
|
|
STDIN/STDOUT/STDERR) will have
|
|
the O_NONBLOCK flag set and hence are in
|
|
non-blocking mode. This option is only
|
|
useful in conjunction with a socket
|
|
unit, as described in
|
|
<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
|
|
to false.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>NotifyAccess=</varname></term>
|
|
<listitem><para>Controls access to the
|
|
service status notification socket, as
|
|
accessible via the
|
|
<citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
call. Takes one of
|
|
<option>none</option> (the default),
|
|
<option>main</option> or
|
|
<option>all</option>. If
|
|
<option>none</option>, no daemon status
|
|
updates are accepted from the service
|
|
processes, all status update messages
|
|
are ignored. If <option>main</option>,
|
|
only service updates sent from the
|
|
main process of the service are
|
|
accepted. If <option>all</option>, all
|
|
services updates from all members of
|
|
the service's control group are
|
|
accepted. This option should be set to
|
|
open access to the notification socket
|
|
when using
|
|
<varname>Type=notify</varname> or
|
|
<varname>WatchdogSec=</varname> (see
|
|
above). If those options are used but
|
|
<varname>NotifyAccess=</varname> is not
|
|
configured, it will be implicitly set
|
|
to
|
|
<option>main</option>.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>Sockets=</varname></term>
|
|
<listitem><para>Specifies the name of
|
|
the socket units this service shall
|
|
inherit the sockets from when the
|
|
service is started. Normally it
|
|
should not be necessary to use this
|
|
setting as all sockets whose unit
|
|
shares the same name as the service
|
|
(ignoring the different suffix of course)
|
|
are passed to the spawned
|
|
process.</para>
|
|
|
|
<para>Note that the same socket may be
|
|
passed to multiple processes at the
|
|
same time. Also note that a different
|
|
service may be activated on incoming
|
|
traffic than inherits the sockets. Or
|
|
in other words: the
|
|
<varname>Service=</varname> setting of
|
|
<filename>.socket</filename> units
|
|
does not have to match the inverse of
|
|
the <varname>Sockets=</varname>
|
|
setting of the
|
|
<filename>.service</filename> it
|
|
refers to.</para>
|
|
|
|
<para>This option may appear more than
|
|
once, in which case the list of socket
|
|
units is merged. If the empty string
|
|
is assigned to this option, the list of
|
|
sockets is reset, all prior uses of
|
|
this setting will have no
|
|
effect.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>StartLimitInterval=</varname></term>
|
|
<term><varname>StartLimitBurst=</varname></term>
|
|
|
|
<listitem><para>Configure service
|
|
start rate limiting. By default,
|
|
services which are started more often
|
|
than 5 times within 10s are not
|
|
permitted to start any more times
|
|
until the 10s interval ends. With
|
|
these two options, this rate limiting
|
|
may be modified. Use
|
|
<varname>StartLimitInterval=</varname>
|
|
to configure the checking interval (defaults to
|
|
<varname>DefaultStartLimitInterval=</varname> in
|
|
manager configuration file, set to 0 to disable
|
|
any kind of rate limiting). Use
|
|
<varname>StartLimitBurst=</varname> to
|
|
configure how many starts per interval
|
|
are allowed (defaults to
|
|
<varname>DefaultStartLimitBurst=</varname> in
|
|
manager configuration file). These
|
|
configuration options are particularly
|
|
useful in conjunction with
|
|
<varname>Restart=</varname>, however
|
|
apply to all kinds of starts
|
|
(including manual), not just those
|
|
triggered by the
|
|
<varname>Restart=</varname> logic.
|
|
Note that units which are configured
|
|
for <varname>Restart=</varname> and
|
|
which reach the start limit are not
|
|
attempted to be restarted anymore,
|
|
however they may still be restarted
|
|
manually at a later point from which
|
|
point on the restart logic is again
|
|
activated. Note that
|
|
<command>systemctl
|
|
reset-failed</command> will cause the
|
|
restart rate counter for a service to
|
|
be flushed, which is useful if the
|
|
administrator wants to manually start
|
|
a service and the start limit
|
|
interferes with
|
|
that.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><varname>StartLimitAction=</varname></term>
|
|
|
|
<listitem><para>Configure the action
|
|
to take if the rate limit configured
|
|
with
|
|
<varname>StartLimitInterval=</varname>
|
|
and
|
|
<varname>StartLimitBurst=</varname> is
|
|
hit. Takes one of
|
|
<option>none</option>,
|
|
<option>reboot</option>,
|
|
<option>reboot-force</option> or
|
|
<option>reboot-immediate</option>. If
|
|
<option>none</option> is set,
|
|
hitting the rate limit will trigger no
|
|
action besides that the start will not
|
|
be
|
|
permitted. <option>reboot</option>
|
|
causes a reboot following the normal
|
|
shutdown procedure (i.e. equivalent to
|
|
<command>systemctl reboot</command>),
|
|
<option>reboot-force</option> causes
|
|
an forced reboot which will terminate
|
|
all processes forcibly but should
|
|
cause no dirty file systems on reboot
|
|
(i.e. equivalent to <command>systemctl
|
|
reboot -f</command>) and
|
|
<option>reboot-immediate</option>
|
|
causes immediate execution of the
|
|
<citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
|
|
system call, which might result in
|
|
data loss. Defaults to
|
|
<option>none</option>.</para></listitem>
|
|
</varlistentry>
|
|
|
|
</variablelist>
|
|
|
|
<para>Check
|
|
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
|
and
|
|
<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
|
|
for more settings.</para>
|
|
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Compatibility Options</title>
|
|
|
|
<para>The following options are also available in the
|
|
<literal>[Service]</literal> section, but exist purely
|
|
for compatibility reasons and should not be used in
|
|
newly written service files.</para>
|
|
|
|
<variablelist class='unit-directives'>
|
|
<varlistentry>
|
|
<term><varname>SysVStartPriority=</varname></term>
|
|
<listitem><para>Set the SysV start
|
|
priority to use to order this service
|
|
in relation to SysV services lacking
|
|
LSB headers. This option is only
|
|
necessary to fix ordering in relation
|
|
to legacy SysV services, that have no
|
|
ordering information encoded in the
|
|
script headers. As such it should only
|
|
be used as temporary compatibility
|
|
option, and not be used in new unit
|
|
files. Almost always it is a better
|
|
choice to add explicit ordering
|
|
directives via
|
|
<varname>After=</varname> or
|
|
<varname>Before=</varname>,
|
|
instead. For more details see
|
|
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
|
|
used, pass an integer value in the
|
|
range 0-99.</para></listitem>
|
|
</varlistentry>
|
|
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
|
|
</refentry>
|