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

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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
        "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">

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<refentry id="systemd.special">

        <refentryinfo>
                <title>systemd.special</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.special</refentrytitle>
                <manvolnum>7</manvolnum>
        </refmeta>

        <refnamediv>
                <refname>systemd.special</refname>
                <refpurpose>special systemd units</refpurpose>
        </refnamediv>

        <refsynopsisdiv>
                <para><filename>emergency.service</filename></para>
                <para><filename>local-fs.target</filename></para>
                <para><filename>network.target</filename></para>
                <para><filename>nss-lookup.target</filename></para>
                <para><filename>remote-fs.target</filename></para>
                <para><filename>rpcbind.target</filename></para>
                <para><filename>rtc-set.target</filename></para>
                <para><filename>shutdown.target</filename></para>
                <para><filename>sigpwr.target</filename></para>
                <para><filename>sockets.target</filename></para>
                <para><filename>swap.target</filename></para>
                <para><filename>syslog.target</filename></para>
                <para><filename>systemd-initctl.service</filename></para>
                <para><filename>systemd-initctl.socket</filename></para>
                <para><filename>systemd-logger.service</filename></para>
                <para><filename>systemd-logger.socket</filename></para>
        </refsynopsisdiv>

        <refsect1>
                <title>Description</title>

                <para>A few units are treated specially by
                systemd. They have special internal semantics and
                cannot be renamed.</para>
        </refsect1>

        <refsect1>
                <title>Special System Units</title>

                <variablelist>
                        <varlistentry>
                                <term><filename>emergency.service</filename></term>
                                <listitem>
                                        <para>A special service unit
                                        that starts an emergency
                                        shell on the main
                                        console. This unit is supposed
                                        to be used with the kernel
                                        command line option
                                        <varname>systemd.default=</varname>
                                        and has otherwise little use.
                                        </para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>local-fs.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to all mount units that
                                        refer to local mount
                                        points. In addition, systemd
                                        adds dependencies of type
                                        Wants to those mounts listed
                                        in
                                        <filename>/etc/fstab</filename>
                                        that have the
                                        <literal>auto</literal> and
                                        <literal>comment=systemd.mount</literal>
                                        mount options set.</para>

                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$local_fs</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>network.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$network</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>nss-lookup.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$named</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>remote-fs.target</filename></term>
                                <listitem>
                                        <para>Similar to <filename>local-fs.target</filename>, but for remote mount points.</para>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$remote-fs</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>rpcbind.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$rpcbind</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>rtc-set.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$time</literal>
                                        facility.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>shutdown.target</filename></term>
                                <listitem>
                                        <para>A special target unit
                                        that terminates the services
                                        on system shutdown.</para>

                                        <para>Services that shall be
                                        terminated on system shutdown
                                        shall add Wants dependencies
                                        from this unit to their
                                        service unit during
                                        installation.</para>

                                        <para>systemd automatically
                                        adds dependencies of type
                                        Conflicts to this target unit
                                        for all SysV init scripts that
                                        shall be terminated in SysV
                                        runlevels 0 or 6.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>sigpwr.target</filename></term>
                                <listitem>
                                        <para>A special target that is
                                        started when systemd receives
                                        the SIGPWR process signal,
                                        which is normally sent by the
                                        kernel or UPS daemons when the
                                        power fails.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>sockets.target</filename></term>
                                <listitem>
                                        <para>A special target unit
                                        that sets up all service
                                        sockets.</para>

                                        <para>Services that can be
                                        socket-activated shall add
                                        Wants dependencies from this
                                        unit to their socket unit
                                        during installation.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>swap.target</filename></term>
                                <listitem>
                                        <para>Similar to
                                        <filename>local-fs.target</filename>, but for swap
                                        partitions and swap
                                        files.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>syslog.target</filename></term>
                                <listitem>
                                        <para>systemd automatically
                                        adds dependencies of type
                                        After to this target unit for
                                        all SysV init scripts with an
                                        LSB header referring to the
                                        <literal>$syslog</literal>
                                        facility.</para>

                                        <para>Administrators should
                                        ensure that this target pulls
                                        in a service unit with the
                                        name or alias of
                                        <filename>@SPECIAL_SYSLOG_NAME@</filename> (or a
                                        socket unit that activates
                                        this service).</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>systemd-initctl.service</filename></term>
                                <listitem>
                                        <para>This provides
                                        compatibility with the SysV
                                        /dev/initctl file system FIFO
                                        for communication with the
                                        init system.</para>
                                        <para>This is a
                                        socket-activated service, see
                                        <filename>system-initctl.socket</filename>.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>systemd-initctl.socket</filename></term>
                                <listitem>
                                        <para>Socket activation unit
                                        for
                                        <filename>system-initctl.service</filename>.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>systemd-logger.service</filename></term>
                                <listitem>
                                        <para>This is used internally
                                        by systemd to provide syslog
                                        logging to started
                                        processes.</para>
                                        <para>This is a
                                        socket-activated service, see
                                        <filename>system-logger.socket</filename>.</para>
                                </listitem>
                        </varlistentry>
                        <varlistentry>
                                <term><filename>systemd-logger.socket</filename></term>
                                <listitem>
                                        <para>Socket activation unit
                                        for
                                        <filename>system-logger.service</filename>.</para>
                                </listitem>
                        </varlistentry>
                </variablelist>
        </refsect1>

        <refsect1>
                <title>Special Session Units</title>

                <para>When systemd runs as a service instance, the
                following special units are available, which have
                similar definitions as their system counterparts:
                <filename>local-fs.target</filename>,
                <filename>remote-fs.target</filename>,
                <filename>shutdown.target</filename>,
                <filename>sockets.target</filename>,
                <filename>swap.target</filename>.</para>
        </refsect1>

        <refsect1>
                  <title>See Also</title>
                  <para>
                          <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                          <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                          <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                          <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                  </para>
        </refsect1>

</refentry>
Commit	Line	Data
9f235308 LP	1	<?xml version='1.0'?> <!---nxml--->
	2	<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
	3	"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
	4
	5	<!--
	6	This file is part of systemd.
	7
	8	Copyright 2010 Lennart Poettering
	9
	10	systemd is free software; you can redistribute it and/or modify it
	11	under the terms of the GNU General Public License as published by
	12	the Free Software Foundation; either version 2 of the License, or
	13	(at your option) any later version.
	14
	15	systemd is distributed in the hope that it will be useful, but
	16	WITHOUT ANY WARRANTY; without even the implied warranty of
	17	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	General Public License for more details.
	19
	20	You should have received a copy of the GNU General Public License
	21	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	22	-->
	23
	24	<refentry id="systemd.special">
	25
	26	<refentryinfo>
	27	<title>systemd.special</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.special</refentrytitle>
	42	<manvolnum>7</manvolnum>
	43	</refmeta>
	44
	45	<refnamediv>
	46	<refname>systemd.special</refname>
	47	<refpurpose>special systemd units</refpurpose>
	48	</refnamediv>
	49
	50	<refsynopsisdiv>
	51	<para><filename>emergency.service</filename></para>
	52	<para><filename>local-fs.target</filename></para>
	53	<para><filename>network.target</filename></para>
	54	<para><filename>nss-lookup.target</filename></para>
	55	<para><filename>remote-fs.target</filename></para>
	56	<para><filename>rpcbind.target</filename></para>
	57	<para><filename>rtc-set.target</filename></para>
	58	<para><filename>shutdown.target</filename></para>
	59	<para><filename>sigpwr.target</filename></para>
	60	<para><filename>sockets.target</filename></para>
	61	<para><filename>swap.target</filename></para>
	62	<para><filename>syslog.target</filename></para>
	63	<para><filename>systemd-initctl.service</filename></para>
	64	<para><filename>systemd-initctl.socket</filename></para>
65	<para><filename>systemd-logger.service</filename></para>
66	<para><filename>systemd-logger.socket</filename></para>
67	</refsynopsisdiv>
68
69	<refsect1>
70	<title>Description</title>
71
72	<para>A few units are treated specially by
73	systemd. They have special internal semantics and
74	cannot be renamed.</para>
75	</refsect1>
76
77	<refsect1>
78	<title>Special System Units</title>
79
80	<variablelist>
81	<varlistentry>
82	<term><filename>emergency.service</filename></term>
83	<listitem>
84	<para>A special service unit
85	that starts an emergency
86	shell on the main
87	console. This unit is supposed
88	to be used with the kernel
89	command line option
90	<varname>systemd.default=</varname>
91	and has otherwise little use.
92	</para>
93	</listitem>
94	</varlistentry>
95	<varlistentry>
96	<term><filename>local-fs.target</filename></term>
97	<listitem>
98	<para>systemd automatically
99	adds dependencies of type
100	After to all mount units that
101	refer to local mount
102	points. In addition, systemd
103	adds dependencies of type
104	Wants to those mounts listed
105	in
106	<filename>/etc/fstab</filename>
107	that have the
108	<literal>auto</literal> and
109	<literal>comment=systemd.mount</literal>
110	mount options set.</para>
111
112	<para>systemd automatically
113	adds dependencies of type
114	After to this target unit for
115	all SysV init scripts with an
116	LSB header referring to the
117	<literal>$local_fs</literal>
118	facility.</para>
119	</listitem>
120	</varlistentry>
121	<varlistentry>
122	<term><filename>network.target</filename></term>
123	<listitem>
124	<para>systemd automatically
125	adds dependencies of type
126	After to this target unit for
127	all SysV init scripts with an
128	LSB header referring to the
129	<literal>$network</literal>
130	facility.</para>
131	</listitem>
132	</varlistentry>
133	<varlistentry>
134	<term><filename>nss-lookup.target</filename></term>
135	<listitem>
136	<para>systemd automatically
137	adds dependencies of type
138	After to this target unit for
139	all SysV init scripts with an
140	LSB header referring to the
141	<literal>$named</literal>
142	facility.</para>
143	</listitem>
144	</varlistentry>
145	<varlistentry>
146	<term><filename>remote-fs.target</filename></term>
147	<listitem>
148	<para>Similar to <filename>local-fs.target</filename>, but for remote mount points.</para>
149	<para>systemd automatically
150	adds dependencies of type
151	After to this target unit for
152	all SysV init scripts with an
153	LSB header referring to the
154	<literal>$remote-fs</literal>
155	facility.</para>
156	</listitem>
157	</varlistentry>
158	<varlistentry>
159	<term><filename>rpcbind.target</filename></term>
160	<listitem>
161	<para>systemd automatically
162	adds dependencies of type
163	After to this target unit for
164	all SysV init scripts with an
165	LSB header referring to the
166	<literal>$rpcbind</literal>
167	facility.</para>
168	</listitem>
169	</varlistentry>
170	<varlistentry>
171	<term><filename>rtc-set.target</filename></term>
172	<listitem>
173	<para>systemd automatically
174	adds dependencies of type
175	After to this target unit for
176	all SysV init scripts with an
177	LSB header referring to the
178	<literal>$time</literal>
179	facility.</para>
180	</listitem>
181	</varlistentry>
182	<varlistentry>
183	<term><filename>shutdown.target</filename></term>
184	<listitem>
185	<para>A special target unit
186	that terminates the services
187	on system shutdown.</para>
188
189	<para>Services that shall be
190	terminated on system shutdown
191	shall add Wants dependencies
192	from this unit to their
193	service unit during
194	installation.</para>
195
196	<para>systemd automatically
197	adds dependencies of type
198	Conflicts to this target unit
199	for all SysV init scripts that
200	shall be terminated in SysV
201	runlevels 0 or 6.</para>
202	</listitem>
203	</varlistentry>
204	<varlistentry>
205	<term><filename>sigpwr.target</filename></term>
206	<listitem>
207	<para>A special target that is
208	started when systemd receives
209	the SIGPWR process signal,
210	which is normally sent by the
211	kernel or UPS daemons when the
212	power fails.</para>
213	</listitem>
214	</varlistentry>
215	<varlistentry>
216	<term><filename>sockets.target</filename></term>
217	<listitem>
218	<para>A special target unit
219	that sets up all service
220	sockets.</para>
221
222	<para>Services that can be
223	socket-activated shall add
224	Wants dependencies from this
225	unit to their socket unit
226	during installation.</para>
227	</listitem>
228	</varlistentry>
229	<varlistentry>
230	<term><filename>swap.target</filename></term>
231	<listitem>
232	<para>Similar to
233	<filename>local-fs.target</filename>, but for swap
234	partitions and swap
235	files.</para>
236	</listitem>
237	</varlistentry>
238	<varlistentry>
239	<term><filename>syslog.target</filename></term>
240	<listitem>
241	<para>systemd automatically
242	adds dependencies of type
243	After to this target unit for
244	all SysV init scripts with an
245	LSB header referring to the
246	<literal>$syslog</literal>
247	facility.</para>
248
249	<para>Administrators should
250	ensure that this target pulls
251	in a service unit with the
252	name or alias of
253	<filename>@SPECIAL_SYSLOG_NAME@</filename> (or a
254	socket unit that activates
255	this service).</para>
256	</listitem>
257	</varlistentry>
258	<varlistentry>
259	<term><filename>systemd-initctl.service</filename></term>
260	<listitem>
261	<para>This provides
262	compatibility with the SysV
263	/dev/initctl file system FIFO
264	for communication with the
265	init system.</para>
266	<para>This is a
267	socket-activated service, see
268	<filename>system-initctl.socket</filename>.</para>
269	</listitem>
270	</varlistentry>
271	<varlistentry>
272	<term><filename>systemd-initctl.socket</filename></term>
273	<listitem>
274	<para>Socket activation unit
275	for
276	<filename>system-initctl.service</filename>.</para>
277	</listitem>
278	</varlistentry>
279	<varlistentry>
280	<term><filename>systemd-logger.service</filename></term>
281	<listitem>
282	<para>This is used internally
283	by systemd to provide syslog
284	logging to started
285	processes.</para>
286	<para>This is a
287	socket-activated service, see
288	<filename>system-logger.socket</filename>.</para>
289	</listitem>
290	</varlistentry>
291	<varlistentry>
292	<term><filename>systemd-logger.socket</filename></term>
293	<listitem>
294	<para>Socket activation unit
295	for
296	<filename>system-logger.service</filename>.</para>
297	</listitem>
298	</varlistentry>
299	</variablelist>
300	</refsect1>
301
302	<refsect1>
303	<title>Special Session Units</title>
304
305	<para>When systemd runs as a service instance, the
306	following special units are available, which have
307	similar definitions as their system counterparts:
308	<filename>local-fs.target</filename>,
309	<filename>remote-fs.target</filename>,
310	<filename>shutdown.target</filename>,
311	<filename>sockets.target</filename>,
312	<filename>swap.target</filename>.</para>
313	</refsect1>
314
315	<refsect1>
316	<title>See Also</title>
317	<para>
318	<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
319	<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
320	<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>
321	<citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>
322	</para>
323	</refsect1>
324
325	</refentry>