systemd.service.xml 10.5 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96
<?xml version='1.0'?> <!--*-nxml-*-->
<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
        "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

<!--
  This file is part of systemd.

  Copyright 2010 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->

<refentry id="systemd.service">
        <refentryinfo>
                <title>systemd.service</title>
                <productname>systemd</productname>

                <authorgroup>
                        <author>
                                <contrib>Developer</contrib>
                                <firstname>Lennart</firstname>
                                <surname>Poettering</surname>
                                <email>lennart@poettering.net</email>
                        </author>
                </authorgroup>
        </refentryinfo>

        <refmeta>
                <refentrytitle>systemd.service</refentrytitle>
                <manvolnum>5</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>systemd.service</refname>
                <refpurpose>systemd service configuration files</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <para><filename>systemd.service</filename></para>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para>A configuration file ending in .service encodes
                information about a process controlled and supervised
                by systemd.</para>

                <para>This man page lists the configuration options
                specific to this unit type. See
                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                for the common options of all unit configuration
                files.</para>
        </refsect1>

        <refsect1>
                <title>Options</title>

                <variablelist>
                        <varlistentry>
                                <term><varname>Type=</varname></term>
                                <listitem>
                                        <para>One of
                                        <literal>forking</literal>,
                                        <literal>simple</literal>,
                                        <literal>finish</literal>,
                                        <literal>dbus</literal>.</para>

                                        <para>If set to
                                        <literal>forking</literal>
                                        (the default) it is expected
                                        that the process configured
                                        with
                                        <varname>ExecStart=</varname>
                                        will start up and call
                                        <function>fork()</function>. The
                                        parent process is expected to
                                        finish when start-up is
                                        complete and all communication
                                        channels set up. The child
                                        continues to run as the main
                                        daemon process. This is the
                                        behaviour of traditional UNIX
                                        daemons. If this setting is
Kay Sievers's avatar
Kay Sievers committed
97
                                        used, it is recommended to also
98 99 100 101
                                        use the
                                        <varname>PIDFile=</varname>
                                        option, so that systemd can
                                        identify the main process of
Kay Sievers's avatar
Kay Sievers committed
102 103 104
                                        the daemon. systemd will proceed
                                        starting follow-up units as soon
                                        as the parent process exits.</para>
105 106 107 108 109 110 111 112

                                        <para>If set to
                                        <literal>simple</literal> (the
                                        recommended value) it is
                                        expected that the process
                                        configured with
                                        <varname>ExecStart=</varname>
                                        is the main process of the
Kay Sievers's avatar
Kay Sievers committed
113
                                        daemon. In this mode,
114 115
                                        communication channels must be
                                        available before the daemon is
Kay Sievers's avatar
Kay Sievers committed
116 117 118
                                        started up (sockets set up by systemd),
                                        as systemd will immediately proceed
                                        starting follow-up units.</para>
119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138

                                        <para>Behaviour of
                                        <literal>finish</literal> is
                                        similar to
                                        <literal>simple</literal>,
                                        however it is expected that
                                        the process has to exit before
                                        systemd starts follow-up
                                        units. <varname>ValidNoProcess=</varname>
                                        is particularly useful for
                                        this type of service.</para>

                                        <para>Behaviour of
                                        <literal>dbus</literal> is
                                        similar to
                                        <literal>simple</literal>,
                                        however it is expected that
                                        the daemon acquires a name on
                                        the D-Bus bus, as configured
                                        by
Kay Sievers's avatar
Kay Sievers committed
139 140 141
                                        <varname>BusName=</varname>. Systemd will
                                        proceed starting follow-up
                                        units after the D-Bus bus name has been
142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172
                                        acquired.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><varname>ValidNoProcess=</varname></term>
                                <listitem>
                                        <para>Takes a boolean value
                                        that specifies whether the service
                                        shall be considered active
                                        even when all its processes
                                        exited. Defaults to <literal>no</literal>.</para>
                                </listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>PIDFile=</varname></term>
                                <listitem>
                                        <para>Takes an absolute file
                                        name pointing to the PID file
                                        of this daemon. Use of this
                                        option is recommended for
                                        services where
                                        <varname>Type=</varname> is
                                        set to
                                        <literal>forking</literal>.</para>
                                </listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>BusName=</varname></term>
                                <listitem>
Kay Sievers's avatar
Kay Sievers committed
173 174
                                        <para>Takes a D-Bus bus name,
                                        where this service is reachable
175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213
                                        as. This option is mandatory
                                        for services where
                                        <varname>Type=</varname> is
                                        set to
                                        <literal>dbus</literal>, but
                                        its use is otherwise
                                        recommended as well if the
                                        process takes a name on the
                                        D-Bus bus.</para>
                                </listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>ExecStart=</varname></term>
                                <listitem>
                                        <para>Takes a command line
                                        that is executed when this
                                        service shall be started
                                        up. The first word of the
                                        command line must be an
                                        absolute file name. It is
                                        mandatory to set this option
                                        for all services.</para>
                                </listitem>
                        </varlistentry>

                </variablelist>
        </refsect1>

        <refsect1>
                  <title>See Also</title>
                  <para>
                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                          <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                          <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                  </para>
        </refsect1>

</refentry>