[thirdparty/systemd.git] / man / systemd.device.xml

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<refentry id="systemd.device">
        <refentryinfo>
                <title>systemd.device</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.device</refentrytitle>
                <manvolnum>5</manvolnum>
        </refmeta>

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

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

        <refsect1>
                <title>Description</title>

                <para>A unit configuration file whose name ends in
                <filename>.device</filename> encodes information about
                a device unit as exposed in the
                sysfs/<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                device tree.</para>

                <para>This unit type has no specific options. See
                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                for the common options of all unit configuration
                files. The common configuration items are configured
                in the generic [Unit] and [Install] sections. A
                seperate [Device] section does not exist, since no
                device-specific options may be configured.</para>

                <para>systemd will automatically create dynamic device
                units for all kernel devices that are marked with the
                "systemd" udev tag (by default all block and network
                devices, and a few others). This may be used to define
                dependencies between devices and other
                units.</para>

                <para>Device units are named after the
                <filename>/sys</filename> and
                <filename>/dev</filename> paths they control. Example:
                the device <filename>/dev/sda5</filename> is exposed
                in systemd as <filename>dev-sda5.device</filename>. For
                details about the escaping logic used to convert a
                file system path to a unit name see
                <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>

        </refsect1>

        <refsect1>
                <title>The udev Database</title>

                <para>The settings of device units may either be
                configured via unit files, or directly from the udev
                database (which is recommended). The following udev
                properties are understood by systemd:</para>

                <variablelist>
                        <varlistentry>
                                <term><varname>SYSTEMD_WANTS=</varname></term>
                                <listitem><para>Adds dependencies of
                                type <varname>Wants</varname> from
                                this unit to all listed units. This
                                may be used to activate aritrary units
                                if a specific device becomes
                                available.</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>SYSTEMD_ALIAS=</varname></term>
                                <listitem><para>Adds an additional
                                alias name to the device unit. This
                                must be an absolute path that is
                                automatically transformed into a unit
                                name. (See above.)</para></listitem>
                        </varlistentry>

                        <varlistentry>
                                <term><varname>ID_MODEL_FROM_DATABASE=</varname></term>
                                <term><varname>ID_MODEL=</varname></term>

                                <listitem><para>If set, this property is
                                used as description string for the
                                device unit.</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>,
                          <citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                  </para>
        </refsect1>

</refentry>
Commit	Line	Data
eec575d8 LP	1	<?xml version='1.0'?> <!---nxml--->
	2	<?xml-stylesheet type="text/xsl" href="http://docbook.sourceforge.net/release/xsl/current/xhtml/docbook.xsl"?>
	3	<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
	4	"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
	5
	6	<!--
	7	This file is part of systemd.
	8
	9	Copyright 2010 Lennart Poettering
	10
	11	systemd is free software; you can redistribute it and/or modify it
	12	under the terms of the GNU General Public License as published by
	13	the Free Software Foundation; either version 2 of the License, or
	14	(at your option) any later version.
	15
	16	systemd is distributed in the hope that it will be useful, but
	17	WITHOUT ANY WARRANTY; without even the implied warranty of
	18	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	19	General Public License for more details.
	20
	21	You should have received a copy of the GNU General Public License
	22	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	23	-->
	24
	25	<refentry id="systemd.device">
	26	<refentryinfo>
	27	<title>systemd.device</title>
	28	<productname>systemd</productname>
	29
	30	<authorgroup>
	31	<author>
	32	<contrib>Developer</contrib>
	33	<firstname>Lennart</firstname>
	34	<surname>Poettering</surname>
	35	<email>lennart@poettering.net</email>
	36	</author>
	37	</authorgroup>
	38	</refentryinfo>
	39
	40	<refmeta>
	41	<refentrytitle>systemd.device</refentrytitle>
	42	<manvolnum>5</manvolnum>
	43	</refmeta>
	44
	45	<refnamediv>
	46	<refname>systemd.device</refname>
	47	<refpurpose>systemd device configuration files</refpurpose>
	48	</refnamediv>
	49
	50	<refsynopsisdiv>
	51	<para><filename>systemd.device</filename></para>
	52	</refsynopsisdiv>
	53
	54	<refsect1>
	55	<title>Description</title>
	56
	57	<para>A unit configuration file whose name ends in
	58	<filename>.device</filename> encodes information about
	59	a device unit as exposed in the
	60	sysfs/<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
	61	device tree.</para>
	62
	63	<para>This unit type has no specific options. See
	64	<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
65	for the common options of all unit configuration
66	files. The common configuration items are configured
67	in the generic [Unit] and [Install] sections. A
68	seperate [Device] section does not exist, since no
69	device-specific options may be configured.</para>
70
71	<para>systemd will automatically create dynamic device
72	units for all kernel devices that are marked with the
73	"systemd" udev tag (by default all block and network
74	devices, and a few others). This may be used to define
75	dependencies between devices and other
76	units.</para>
77
78	<para>Device units are named after the
79	<filename>/sys</filename> and
80	<filename>/dev</filename> paths they control. Example:
81	the device <filename>/dev/sda5</filename> is exposed
82	in systemd as <filename>dev-sda5.device</filename>. For
83	details about the escaping logic used to convert a
84	file system path to a unit name see
85	<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
86
87	</refsect1>
88
89	<refsect1>
90	<title>The udev Database</title>
91
92	<para>The settings of device units may either be
93	configured via unit files, or directly from the udev
94	database (which is recommended). The following udev
95	properties are understood by systemd:</para>
96
97	<variablelist>
98	<varlistentry>
99	<term><varname>SYSTEMD_WANTS=</varname></term>
100	<listitem><para>Adds dependencies of
101	type <varname>Wants</varname> from
102	this unit to all listed units. This
103	may be used to activate aritrary units
104	if a specific device becomes
105	available.</para></listitem>
106	</varlistentry>
107
108	<varlistentry>
109	<term><varname>SYSTEMD_ALIAS=</varname></term>
110	<listitem><para>Adds an additional
111	alias name to the device unit. This
112	must be an absolute path that is
113	automatically transformed into a unit
114	name. (See above.)</para></listitem>
115	</varlistentry>
116
117	<varlistentry>
118	<term><varname>ID_MODEL_FROM_DATABASE=</varname></term>
119	<term><varname>ID_MODEL=</varname></term>
120
121	<listitem><para>If set, this property is
122	used as description string for the
123	device unit.</para></listitem>
124	</varlistentry>
125
126	</variablelist>
127
128
129	</refsect1>
130
131	<refsect1>
132	<title>See Also</title>
133	<para>
134	<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
135	<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
136	<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
137	<citerefentry><refentrytitle>udev</refentrytitle><manvolnum>7</manvolnum></citerefentry>
138	</para>
139	</refsect1>
140
141	</refentry>