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b9e74c39 | 1 | <?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*--> |
9e632bf7 | 2 | <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" |
12b42c76 | 3 | "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> |
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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 | |
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11 | under the terms of the GNU Lesser General Public License as published by |
12 | the Free Software Foundation; either version 2.1 of the License, or | |
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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 | |
5430f7f2 | 18 | Lesser General Public License for more details. |
9e632bf7 | 19 | |
5430f7f2 | 20 | You should have received a copy of the GNU Lesser General Public License |
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21 | along with systemd; If not, see <http://www.gnu.org/licenses/>. |
22 | --> | |
23 | ||
dfdebb1b | 24 | <refentry id="systemd" |
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25 | xmlns:xi="http://www.w3.org/2001/XInclude"> |
26 | ||
27 | <refentryinfo> | |
28 | <title>systemd</title> | |
29 | <productname>systemd</productname> | |
30 | ||
31 | <authorgroup> | |
32 | <author> | |
33 | <contrib>Developer</contrib> | |
34 | <firstname>Lennart</firstname> | |
35 | <surname>Poettering</surname> | |
36 | <email>lennart@poettering.net</email> | |
37 | </author> | |
38 | </authorgroup> | |
39 | </refentryinfo> | |
40 | ||
41 | <refmeta> | |
42 | <refentrytitle>systemd</refentrytitle> | |
43 | <manvolnum>1</manvolnum> | |
44 | </refmeta> | |
45 | ||
46 | <refnamediv> | |
47 | <refname>systemd</refname> | |
48 | <refname>init</refname> | |
49 | <refpurpose>systemd system and service manager</refpurpose> | |
50 | </refnamediv> | |
51 | ||
52 | <refsynopsisdiv> | |
53 | <cmdsynopsis> | |
54 | <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command> | |
55 | </cmdsynopsis> | |
56 | <cmdsynopsis> | |
57 | <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command> | |
58 | </cmdsynopsis> | |
59 | </refsynopsisdiv> | |
60 | ||
61 | <refsect1> | |
62 | <title>Description</title> | |
63 | ||
64 | <para>systemd is a system and service manager for Linux operating | |
65 | systems. When run as first process on boot (as PID 1), it acts as | |
66 | init system that brings up and maintains userspace | |
67 | services.</para> | |
68 | ||
69 | <para>For compatibility with SysV, if systemd is called as | |
70 | <command>init</command> and a PID that is not 1, it will execute | |
71 | <command>telinit</command> and pass all command line arguments | |
72 | unmodified. That means <command>init</command> and | |
73 | <command>telinit</command> are mostly equivalent when invoked from | |
74 | normal login sessions. See | |
75 | <citerefentry><refentrytitle>telinit</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
76 | for more information.</para> | |
77 | ||
78 | <para>When run as a system instance, systemd interprets the | |
79 | configuration file <filename>system.conf</filename> and the files | |
80 | in <filename>system.conf.d</filename> directories; when run as a | |
81 | user instance, systemd interprets the configuration file | |
82 | <filename>user.conf</filename> and the files in | |
83 | <filename>user.conf.d</filename> directories. See | |
84 | <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
85 | for more information.</para> | |
86 | </refsect1> | |
87 | ||
88 | <refsect1> | |
89 | <title>Options</title> | |
90 | ||
91 | <para>The following options are understood:</para> | |
92 | ||
93 | <variablelist> | |
94 | <varlistentry> | |
95 | <term><option>--test</option></term> | |
96 | ||
97 | <listitem><para>Determine startup sequence, dump it and exit. | |
98 | This is an option useful for debugging only.</para></listitem> | |
99 | </varlistentry> | |
100 | <varlistentry> | |
101 | <term><option>--dump-configuration-items</option></term> | |
102 | ||
103 | <listitem><para>Dump understood unit configuration items. This | |
104 | outputs a terse but complete list of configuration items | |
105 | understood in unit definition files.</para></listitem> | |
106 | </varlistentry> | |
107 | <varlistentry> | |
108 | <term><option>--unit=</option></term> | |
109 | ||
110 | <listitem><para>Set default unit to activate on startup. If | |
111 | not specified, defaults to | |
112 | <filename>default.target</filename>.</para></listitem> | |
113 | </varlistentry> | |
114 | <varlistentry> | |
115 | <term><option>--system</option></term> | |
116 | <term><option>--user</option></term> | |
117 | ||
118 | <listitem><para>For <option>--system</option>, tell systemd to | |
119 | run a system instance, even if the process ID is not 1, i.e. | |
120 | systemd is not run as init process. <option>--user</option> | |
121 | does the opposite, running a user instance even if the process | |
b938cb90 | 122 | ID is 1. Normally, it should not be necessary to pass these |
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123 | options, as systemd automatically detects the mode it is |
124 | started in. These options are hence of little use except for | |
125 | debugging. Note that it is not supported booting and | |
126 | maintaining a full system with systemd running in | |
127 | <option>--system</option> mode, but PID not 1. In practice, | |
128 | passing <option>--system</option> explicitly is only useful in | |
129 | conjunction with <option>--test</option>.</para></listitem> | |
130 | </varlistentry> | |
131 | <varlistentry> | |
132 | <term><option>--dump-core</option></term> | |
133 | ||
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134 | <listitem><para>Enable core dumping on crash. This switch has |
135 | no effect when running as user instance. This setting may also | |
136 | be enabled during boot on the kernel command line via the | |
137 | <varname>systemd.dump_core=</varname> option, see | |
138 | below.</para></listitem> | |
798d3a52 | 139 | </varlistentry> |
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140 | |
141 | <varlistentry> | |
142 | <term><option>--crash-vt=</option><replaceable>VT</replaceable></term> | |
143 | ||
144 | <listitem><para>Switch to a specific virtual console (VT) on | |
b938cb90 | 145 | crash. Takes a positive integer in the range 1–63, or a |
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146 | boolean argument. If an integer is passed, selects which VT to |
147 | switch to. If <constant>yes</constant>, the VT kernel messages | |
148 | are written to is selected. If <constant>no</constant>, no VT | |
149 | switch is attempted. This switch has no effect when running as | |
150 | user instance. This setting may also be enabled during boot, | |
151 | on the kernel command line via the | |
152 | <varname>systemd.crash_vt=</varname> option, see | |
153 | below.</para></listitem> | |
154 | </varlistentry> | |
155 | ||
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156 | <varlistentry> |
157 | <term><option>--crash-shell</option></term> | |
158 | ||
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159 | <listitem><para>Run a shell on crash. This switch has no |
160 | effect when running as user instance. This setting may also be | |
161 | enabled during boot, on the kernel command line via the | |
162 | <varname>systemd.crash_shell=</varname> option, see | |
163 | below.</para></listitem> | |
798d3a52 | 164 | </varlistentry> |
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165 | |
166 | <varlistentry> | |
167 | <term><option>--crash-reboot</option></term> | |
168 | ||
169 | <listitem><para>Automatically reboot the system on crash. This | |
170 | switch has no effect when running as user instance. This | |
171 | setting may also be enabled during boot, on the kernel command | |
172 | line via the <varname>systemd.crash_reboot=</varname> option, | |
173 | see below.</para></listitem> | |
174 | </varlistentry> | |
175 | ||
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176 | <varlistentry> |
177 | <term><option>--confirm-spawn</option></term> | |
178 | ||
179 | <listitem><para>Ask for confirmation when spawning processes. | |
180 | This switch has no effect when run as user | |
181 | instance.</para></listitem> | |
182 | </varlistentry> | |
183 | <varlistentry> | |
184 | <term><option>--show-status=</option></term> | |
185 | ||
186 | <listitem><para>Show terse service status information while | |
187 | booting. This switch has no effect when run as user instance. | |
188 | Takes a boolean argument which may be omitted which is | |
189 | interpreted as <option>true</option>.</para></listitem> | |
190 | </varlistentry> | |
191 | <varlistentry> | |
192 | <term><option>--log-target=</option></term> | |
193 | ||
194 | <listitem><para>Set log target. Argument must be one of | |
195 | <option>console</option>, | |
196 | <option>journal</option>, | |
197 | <option>kmsg</option>, | |
198 | <option>journal-or-kmsg</option>, | |
199 | <option>null</option>.</para></listitem> | |
200 | </varlistentry> | |
201 | <varlistentry> | |
202 | <term><option>--log-level=</option></term> | |
203 | ||
204 | <listitem><para>Set log level. As | |
205 | argument this accepts a numerical log | |
206 | level or the well-known <citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
207 | symbolic names (lowercase): | |
208 | <option>emerg</option>, | |
209 | <option>alert</option>, | |
210 | <option>crit</option>, | |
211 | <option>err</option>, | |
212 | <option>warning</option>, | |
213 | <option>notice</option>, | |
214 | <option>info</option>, | |
215 | <option>debug</option>.</para></listitem> | |
216 | </varlistentry> | |
217 | <varlistentry> | |
218 | <term><option>--log-color=</option></term> | |
219 | ||
220 | <listitem><para>Highlight important log messages. Argument is | |
221 | a boolean value. If the argument is omitted, it defaults to | |
222 | <option>true</option>.</para></listitem> | |
223 | </varlistentry> | |
224 | <varlistentry> | |
225 | <term><option>--log-location=</option></term> | |
226 | ||
227 | <listitem><para>Include code location in log messages. This is | |
228 | mostly relevant for debugging purposes. Argument is a boolean | |
229 | value. If the argument is omitted it defaults to | |
230 | <option>true</option>.</para></listitem> | |
231 | </varlistentry> | |
232 | <varlistentry> | |
233 | <term><option>--default-standard-output=</option></term> | |
234 | <term><option>--default-standard-error=</option></term> | |
235 | ||
236 | <listitem><para>Sets the default output or error output for | |
237 | all services and sockets, respectively. That is, controls the | |
238 | default for <option>StandardOutput=</option> and | |
239 | <option>StandardError=</option> (see | |
240 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
241 | for details). Takes one of | |
242 | <option>inherit</option>, | |
243 | <option>null</option>, | |
244 | <option>tty</option>, | |
245 | <option>journal</option>, | |
246 | <option>journal+console</option>, | |
247 | <option>syslog</option>, | |
248 | <option>syslog+console</option>, | |
249 | <option>kmsg</option>, | |
250 | <option>kmsg+console</option>. If the | |
251 | argument is omitted | |
252 | <option>--default-standard-output=</option> defaults to | |
253 | <option>journal</option> and | |
254 | <option>--default-standard-error=</option> to | |
255 | <option>inherit</option>.</para></listitem> | |
256 | </varlistentry> | |
257 | ||
258 | <xi:include href="standard-options.xml" xpointer="help" /> | |
259 | <xi:include href="standard-options.xml" xpointer="version" /> | |
260 | </variablelist> | |
261 | </refsect1> | |
262 | ||
263 | <refsect1> | |
264 | <title>Concepts</title> | |
265 | ||
266 | <para>systemd provides a dependency system between various | |
267 | entities called "units" of 12 different types. Units encapsulate | |
268 | various objects that are relevant for system boot-up and | |
269 | maintenance. The majority of units are configured in unit | |
270 | configuration files, whose syntax and basic set of options is | |
271 | described in | |
272 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
273 | however some are created automatically from other configuration, | |
274 | dynamically from system state or programmatically at runtime. | |
275 | Units may be "active" (meaning started, bound, plugged in, ..., | |
276 | depending on the unit type, see below), or "inactive" (meaning | |
277 | stopped, unbound, unplugged, ...), as well as in the process of | |
278 | being activated or deactivated, i.e. between the two states (these | |
279 | states are called "activating", "deactivating"). A special | |
280 | "failed" state is available as well, which is very similar to | |
281 | "inactive" and is entered when the service failed in some way | |
282 | (process returned error code on exit, or crashed, or an operation | |
283 | timed out). If this state is entered, the cause will be logged, | |
284 | for later reference. Note that the various unit types may have a | |
285 | number of additional substates, which are mapped to the five | |
286 | generalized unit states described here.</para> | |
287 | ||
288 | <para>The following unit types are available:</para> | |
289 | ||
290 | <orderedlist> | |
291 | <listitem><para>Service units, which start and control daemons | |
b938cb90 | 292 | and the processes they consist of. For details, see |
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293 | <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
294 | ||
295 | <listitem><para>Socket units, which encapsulate local IPC or | |
296 | network sockets in the system, useful for socket-based | |
b938cb90 | 297 | activation. For details about socket units, see |
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298 | <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
299 | for details on socket-based activation and other forms of | |
300 | activation, see | |
301 | <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem> | |
302 | ||
303 | <listitem><para>Target units are useful to group units, or | |
304 | provide well-known synchronization points during boot-up, see | |
305 | <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
306 | ||
307 | <listitem><para>Device units expose kernel devices in systemd | |
308 | and may be used to implement device-based activation. For | |
b938cb90 | 309 | details, see |
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310 | <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
311 | ||
312 | <listitem><para>Mount units control mount points in the file | |
313 | system, for details see | |
314 | <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
315 | ||
316 | <listitem><para>Automount units provide automount capabilities, | |
317 | for on-demand mounting of file systems as well as parallelized | |
318 | boot-up. See | |
319 | <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
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320 | |
321 | <listitem><para>Timer units are useful for triggering activation | |
322 | of other units based on timers. You may find details in | |
323 | <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
324 | ||
325 | <listitem><para>Swap units are very similar to mount units and | |
326 | encapsulate memory swap partitions or files of the operating | |
327 | system. They are described in | |
328 | <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
329 | ||
330 | <listitem><para>Path units may be used to activate other | |
331 | services when file system objects change or are modified. See | |
332 | <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
333 | ||
334 | <listitem><para>Slice units may be used to group units which | |
335 | manage system processes (such as service and scope units) in a | |
336 | hierarchical tree for resource management purposes. See | |
337 | <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
338 | ||
339 | <listitem><para>Scope units are similar to service units, but | |
340 | manage foreign processes instead of starting them as well. See | |
341 | <citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
342 | ||
343 | </orderedlist> | |
344 | ||
345 | <para>Units are named as their configuration files. Some units | |
346 | have special semantics. A detailed list is available in | |
347 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> | |
348 | ||
349 | <para>systemd knows various kinds of dependencies, including | |
350 | positive and negative requirement dependencies (i.e. | |
351 | <varname>Requires=</varname> and <varname>Conflicts=</varname>) as | |
352 | well as ordering dependencies (<varname>After=</varname> and | |
353 | <varname>Before=</varname>). NB: ordering and requirement | |
354 | dependencies are orthogonal. If only a requirement dependency | |
355 | exists between two units (e.g. <filename>foo.service</filename> | |
356 | requires <filename>bar.service</filename>), but no ordering | |
357 | dependency (e.g. <filename>foo.service</filename> after | |
358 | <filename>bar.service</filename>) and both are requested to start, | |
359 | they will be started in parallel. It is a common pattern that both | |
360 | requirement and ordering dependencies are placed between two | |
361 | units. Also note that the majority of dependencies are implicitly | |
362 | created and maintained by systemd. In most cases, it should be | |
363 | unnecessary to declare additional dependencies manually, however | |
364 | it is possible to do this.</para> | |
365 | ||
366 | <para>Application programs and units (via dependencies) may | |
367 | request state changes of units. In systemd, these requests are | |
368 | encapsulated as 'jobs' and maintained in a job queue. Jobs may | |
369 | succeed or can fail, their execution is ordered based on the | |
370 | ordering dependencies of the units they have been scheduled | |
371 | for.</para> | |
372 | ||
373 | <para>On boot systemd activates the target unit | |
374 | <filename>default.target</filename> whose job is to activate | |
375 | on-boot services and other on-boot units by pulling them in via | |
b938cb90 | 376 | dependencies. Usually, the unit name is just an alias (symlink) for |
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377 | either <filename>graphical.target</filename> (for fully-featured |
378 | boots into the UI) or <filename>multi-user.target</filename> (for | |
379 | limited console-only boots for use in embedded or server | |
380 | environments, or similar; a subset of graphical.target). However, | |
381 | it is at the discretion of the administrator to configure it as an | |
382 | alias to any other target unit. See | |
383 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
384 | for details about these target units.</para> | |
385 | ||
386 | <para>Processes systemd spawns are placed in individual Linux | |
387 | control groups named after the unit which they belong to in the | |
388 | private systemd hierarchy. (see <ulink | |
389 | url="https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink> | |
390 | for more information about control groups, or short "cgroups"). | |
391 | systemd uses this to effectively keep track of processes. Control | |
392 | group information is maintained in the kernel, and is accessible | |
393 | via the file system hierarchy (beneath | |
394 | <filename>/sys/fs/cgroup/systemd/</filename>), or in tools such as | |
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395 | <citerefentry project='man-pages'><refentrytitle>systemd-cgls</refentrytitle><manvolnum>1</manvolnum></citerefentry> |
396 | or | |
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397 | <citerefentry project='man-pages'><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry> |
398 | (<command>ps xawf -eo pid,user,cgroup,args</command> is | |
399 | particularly useful to list all processes and the systemd units | |
400 | they belong to.).</para> | |
401 | ||
402 | <para>systemd is compatible with the SysV init system to a large | |
403 | degree: SysV init scripts are supported and simply read as an | |
404 | alternative (though limited) configuration file format. The SysV | |
405 | <filename>/dev/initctl</filename> interface is provided, and | |
406 | compatibility implementations of the various SysV client tools are | |
407 | available. In addition to that, various established Unix | |
408 | functionality such as <filename>/etc/fstab</filename> or the | |
409 | <filename>utmp</filename> database are supported.</para> | |
410 | ||
411 | <para>systemd has a minimal transaction system: if a unit is | |
412 | requested to start up or shut down it will add it and all its | |
413 | dependencies to a temporary transaction. Then, it will verify if | |
414 | the transaction is consistent (i.e. whether the ordering of all | |
415 | units is cycle-free). If it is not, systemd will try to fix it up, | |
416 | and removes non-essential jobs from the transaction that might | |
417 | remove the loop. Also, systemd tries to suppress non-essential | |
418 | jobs in the transaction that would stop a running service. Finally | |
419 | it is checked whether the jobs of the transaction contradict jobs | |
420 | that have already been queued, and optionally the transaction is | |
421 | aborted then. If all worked out and the transaction is consistent | |
422 | and minimized in its impact it is merged with all already | |
423 | outstanding jobs and added to the run queue. Effectively this | |
424 | means that before executing a requested operation, systemd will | |
425 | verify that it makes sense, fixing it if possible, and only | |
426 | failing if it really cannot work.</para> | |
427 | ||
428 | <para>Systemd contains native implementations of various tasks | |
429 | that need to be executed as part of the boot process. For example, | |
430 | it sets the hostname or configures the loopback network device. It | |
431 | also sets up and mounts various API file systems, such as | |
432 | <filename>/sys</filename> or <filename>/proc</filename>.</para> | |
433 | ||
434 | <para>For more information about the concepts and | |
435 | ideas behind systemd, please refer to the | |
436 | <ulink url="http://0pointer.de/blog/projects/systemd.html">Original Design Document</ulink>.</para> | |
437 | ||
438 | <para>Note that some but not all interfaces provided | |
439 | by systemd are covered by the | |
440 | <ulink url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface | |
441 | Stability Promise</ulink>.</para> | |
442 | ||
443 | <para>Units may be generated dynamically at boot and system | |
444 | manager reload time, for example based on other configuration | |
b938cb90 | 445 | files or parameters passed on the kernel command line. For details, see |
b1c1a519 | 446 | <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> |
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447 | |
448 | <para>Systems which invoke systemd in a container or initrd | |
449 | environment should implement the | |
450 | <ulink url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container Interface</ulink> or | |
451 | <ulink url="http://www.freedesktop.org/wiki/Software/systemd/InitrdInterface">initrd Interface</ulink> | |
452 | specifications, respectively.</para> | |
453 | </refsect1> | |
454 | ||
455 | <refsect1> | |
456 | <title>Directories</title> | |
457 | ||
458 | <variablelist> | |
459 | <varlistentry> | |
460 | <term>System unit directories</term> | |
461 | ||
462 | <listitem><para>The systemd system manager reads unit | |
463 | configuration from various directories. Packages that want to | |
464 | install unit files shall place them in the directory returned | |
465 | by <command>pkg-config systemd | |
466 | --variable=systemdsystemunitdir</command>. Other directories | |
467 | checked are <filename>/usr/local/lib/systemd/system</filename> | |
12b42c76 | 468 | and <filename>/usr/lib/systemd/system</filename>. User |
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469 | configuration always takes precedence. <command>pkg-config |
470 | systemd --variable=systemdsystemconfdir</command> returns the | |
471 | path of the system configuration directory. Packages should | |
472 | alter the content of these directories only with the | |
473 | <command>enable</command> and <command>disable</command> | |
474 | commands of the | |
475 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
476 | tool. Full list of directories is provided in | |
477 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. | |
478 | </para></listitem> | |
479 | </varlistentry> | |
480 | </variablelist> | |
481 | ||
482 | <variablelist> | |
483 | <varlistentry> | |
484 | <term>User unit directories</term> | |
485 | ||
486 | <listitem><para>Similar rules apply for the user unit | |
487 | directories. However, here the | |
488 | <ulink url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG | |
489 | Base Directory specification</ulink> is followed to find | |
490 | units. Applications should place their unit files in the | |
491 | directory returned by <command>pkg-config systemd | |
492 | --variable=systemduserunitdir</command>. Global configuration | |
493 | is done in the directory reported by <command>pkg-config | |
494 | systemd --variable=systemduserconfdir</command>. The | |
495 | <command>enable</command> and <command>disable</command> | |
496 | commands of the | |
497 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
498 | tool can handle both global (i.e. for all users) and private | |
499 | (for one user) enabling/disabling of units. Full list of | |
500 | directories is provided in | |
501 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. | |
502 | </para></listitem> | |
503 | </varlistentry> | |
504 | </variablelist> | |
505 | ||
506 | <variablelist> | |
507 | <varlistentry> | |
508 | <term>SysV init scripts directory</term> | |
509 | ||
510 | <listitem><para>The location of the SysV init script directory | |
511 | varies between distributions. If systemd cannot find a native | |
512 | unit file for a requested service, it will look for a SysV | |
513 | init script of the same name (with the | |
514 | <filename>.service</filename> suffix | |
515 | removed).</para></listitem> | |
516 | </varlistentry> | |
517 | </variablelist> | |
518 | ||
519 | <variablelist> | |
520 | <varlistentry> | |
521 | <term>SysV runlevel link farm directory</term> | |
522 | ||
523 | <listitem><para>The location of the SysV runlevel link farm | |
524 | directory varies between distributions. systemd will take the | |
525 | link farm into account when figuring out whether a service | |
526 | shall be enabled. Note that a service unit with a native unit | |
527 | configuration file cannot be started by activating it in the | |
528 | SysV runlevel link farm.</para></listitem> | |
529 | </varlistentry> | |
530 | </variablelist> | |
531 | </refsect1> | |
532 | ||
533 | <refsect1> | |
534 | <title>Signals</title> | |
535 | ||
536 | <variablelist> | |
537 | <varlistentry> | |
538 | <term><constant>SIGTERM</constant></term> | |
539 | ||
540 | <listitem><para>Upon receiving this signal the systemd system | |
541 | manager serializes its state, reexecutes itself and | |
542 | deserializes the saved state again. This is mostly equivalent | |
543 | to <command>systemctl daemon-reexec</command>.</para> | |
544 | ||
545 | <para>systemd user managers will start the | |
546 | <filename>exit.target</filename> unit when this signal is | |
547 | received. This is mostly equivalent to <command>systemctl | |
548 | --user start exit.target</command>.</para></listitem> | |
549 | </varlistentry> | |
550 | ||
551 | <varlistentry> | |
552 | <term><constant>SIGINT</constant></term> | |
553 | ||
554 | <listitem><para>Upon receiving this signal the systemd system | |
555 | manager will start the | |
556 | <filename>ctrl-alt-del.target</filename> unit. This is mostly | |
557 | equivalent to <command>systemctl start | |
558 | ctl-alt-del.target</command>. If this signal is received more | |
a8eaaee7 | 559 | than 7 times per 2s, an immediate reboot is triggered. |
798d3a52 | 560 | Note that pressing Ctrl-Alt-Del on the console will trigger |
b938cb90 | 561 | this signal. Hence, if a reboot is hanging, pressing |
798d3a52 ZJS |
562 | Ctrl-Alt-Del more than 7 times in 2s is a relatively safe way |
563 | to trigger an immediate reboot.</para> | |
564 | ||
565 | <para>systemd user managers treat this signal the same way as | |
566 | <constant>SIGTERM</constant>.</para></listitem> | |
567 | </varlistentry> | |
568 | ||
569 | <varlistentry> | |
570 | <term><constant>SIGWINCH</constant></term> | |
571 | ||
572 | <listitem><para>When this signal is received the systemd | |
573 | system manager will start the | |
574 | <filename>kbrequest.target</filename> unit. This is mostly | |
575 | equivalent to <command>systemctl start | |
576 | kbrequest.target</command>.</para> | |
577 | ||
578 | <para>This signal is ignored by systemd user | |
579 | managers.</para></listitem> | |
580 | </varlistentry> | |
581 | ||
582 | <varlistentry> | |
583 | <term><constant>SIGPWR</constant></term> | |
584 | ||
585 | <listitem><para>When this signal is received the systemd | |
586 | manager will start the <filename>sigpwr.target</filename> | |
587 | unit. This is mostly equivalent to <command>systemctl start | |
588 | sigpwr.target</command>.</para></listitem> | |
589 | </varlistentry> | |
590 | ||
591 | <varlistentry> | |
592 | <term><constant>SIGUSR1</constant></term> | |
593 | ||
594 | <listitem><para>When this signal is received the systemd | |
595 | manager will try to reconnect to the D-Bus | |
596 | bus.</para></listitem> | |
597 | </varlistentry> | |
598 | ||
599 | <varlistentry> | |
600 | <term><constant>SIGUSR2</constant></term> | |
601 | ||
602 | <listitem><para>When this signal is received the systemd | |
b938cb90 | 603 | manager will log its complete state in human-readable form. |
798d3a52 ZJS |
604 | The data logged is the same as printed by |
605 | <command>systemd-analyze dump</command>.</para></listitem> | |
606 | </varlistentry> | |
607 | ||
608 | <varlistentry> | |
609 | <term><constant>SIGHUP</constant></term> | |
610 | ||
611 | <listitem><para>Reloads the complete daemon configuration. | |
612 | This is mostly equivalent to <command>systemctl | |
613 | daemon-reload</command>.</para></listitem> | |
614 | </varlistentry> | |
615 | ||
616 | <varlistentry> | |
617 | <term><constant>SIGRTMIN+0</constant></term> | |
618 | ||
619 | <listitem><para>Enters default mode, starts the | |
620 | <filename>default.target</filename> unit. This is mostly | |
621 | equivalent to <command>systemctl start | |
622 | default.target</command>.</para></listitem> | |
623 | </varlistentry> | |
624 | ||
625 | <varlistentry> | |
626 | <term><constant>SIGRTMIN+1</constant></term> | |
627 | ||
628 | <listitem><para>Enters rescue mode, starts the | |
629 | <filename>rescue.target</filename> unit. This is mostly | |
630 | equivalent to <command>systemctl isolate | |
631 | rescue.target</command>.</para></listitem> | |
632 | </varlistentry> | |
633 | ||
634 | <varlistentry> | |
635 | <term><constant>SIGRTMIN+2</constant></term> | |
636 | ||
637 | <listitem><para>Enters emergency mode, starts the | |
638 | <filename>emergency.service</filename> unit. This is mostly | |
639 | equivalent to <command>systemctl isolate | |
640 | emergency.service</command>.</para></listitem> | |
641 | </varlistentry> | |
642 | ||
643 | <varlistentry> | |
644 | <term><constant>SIGRTMIN+3</constant></term> | |
645 | ||
646 | <listitem><para>Halts the machine, starts the | |
647 | <filename>halt.target</filename> unit. This is mostly | |
648 | equivalent to <command>systemctl start | |
649 | halt.target</command>.</para></listitem> | |
650 | </varlistentry> | |
651 | ||
652 | <varlistentry> | |
653 | <term><constant>SIGRTMIN+4</constant></term> | |
654 | ||
655 | <listitem><para>Powers off the machine, starts the | |
656 | <filename>poweroff.target</filename> unit. This is mostly | |
657 | equivalent to <command>systemctl start | |
658 | poweroff.target</command>.</para></listitem> | |
659 | </varlistentry> | |
660 | ||
661 | <varlistentry> | |
662 | <term><constant>SIGRTMIN+5</constant></term> | |
663 | ||
664 | <listitem><para>Reboots the machine, starts the | |
665 | <filename>reboot.target</filename> unit. This is mostly | |
666 | equivalent to <command>systemctl start | |
667 | reboot.target</command>.</para></listitem> | |
668 | </varlistentry> | |
669 | ||
670 | <varlistentry> | |
671 | <term><constant>SIGRTMIN+6</constant></term> | |
672 | ||
673 | <listitem><para>Reboots the machine via kexec, starts the | |
674 | <filename>kexec.target</filename> unit. This is mostly | |
675 | equivalent to <command>systemctl start | |
676 | kexec.target</command>.</para></listitem> | |
677 | </varlistentry> | |
678 | ||
679 | <varlistentry> | |
680 | <term><constant>SIGRTMIN+13</constant></term> | |
681 | ||
682 | <listitem><para>Immediately halts the machine.</para></listitem> | |
683 | </varlistentry> | |
684 | ||
685 | <varlistentry> | |
686 | <term><constant>SIGRTMIN+14</constant></term> | |
687 | ||
688 | <listitem><para>Immediately powers off the machine.</para></listitem> | |
689 | </varlistentry> | |
690 | ||
691 | <varlistentry> | |
692 | <term><constant>SIGRTMIN+15</constant></term> | |
693 | ||
694 | <listitem><para>Immediately reboots the machine.</para></listitem> | |
695 | </varlistentry> | |
696 | ||
697 | <varlistentry> | |
698 | <term><constant>SIGRTMIN+16</constant></term> | |
699 | ||
700 | <listitem><para>Immediately reboots the machine with kexec.</para></listitem> | |
701 | </varlistentry> | |
702 | ||
703 | <varlistentry> | |
704 | <term><constant>SIGRTMIN+20</constant></term> | |
705 | ||
706 | <listitem><para>Enables display of status messages on the | |
707 | console, as controlled via | |
708 | <varname>systemd.show_status=1</varname> on the kernel command | |
709 | line.</para></listitem> | |
710 | </varlistentry> | |
711 | ||
712 | <varlistentry> | |
713 | <term><constant>SIGRTMIN+21</constant></term> | |
714 | ||
715 | <listitem><para>Disables display of | |
716 | status messages on the console, as | |
717 | controlled via | |
718 | <varname>systemd.show_status=0</varname> | |
719 | on the kernel command | |
720 | line.</para></listitem> | |
721 | </varlistentry> | |
722 | ||
723 | <varlistentry> | |
724 | <term><constant>SIGRTMIN+22</constant></term> | |
725 | <term><constant>SIGRTMIN+23</constant></term> | |
726 | ||
727 | <listitem><para>Sets the log level to <literal>debug</literal> | |
728 | (or <literal>info</literal> on | |
729 | <constant>SIGRTMIN+23</constant>), as controlled via | |
730 | <varname>systemd.log_level=debug</varname> (or | |
731 | <varname>systemd.log_level=info</varname> on | |
732 | <constant>SIGRTMIN+23</constant>) on the kernel command | |
733 | line.</para></listitem> | |
734 | </varlistentry> | |
735 | ||
736 | <varlistentry> | |
737 | <term><constant>SIGRTMIN+24</constant></term> | |
738 | ||
739 | <listitem><para>Immediately exits the manager (only available | |
740 | for --user instances).</para></listitem> | |
741 | </varlistentry> | |
742 | ||
743 | <varlistentry> | |
744 | <term><constant>SIGRTMIN+26</constant></term> | |
745 | <term><constant>SIGRTMIN+27</constant></term> | |
746 | <term><constant>SIGRTMIN+28</constant></term> | |
747 | ||
748 | <listitem><para>Sets the log level to | |
749 | <literal>journal-or-kmsg</literal> (or | |
750 | <literal>console</literal> on | |
751 | <constant>SIGRTMIN+27</constant>, <literal>kmsg</literal> on | |
752 | <constant>SIGRTMIN+28</constant>), as controlled via | |
753 | <varname>systemd.log_target=journal-or-kmsg</varname> (or | |
754 | <varname>systemd.log_target=console</varname> on | |
755 | <constant>SIGRTMIN+27</constant> or | |
756 | <varname>systemd.log_target=kmsg</varname> on | |
757 | <constant>SIGRTMIN+28</constant>) on the kernel command | |
758 | line.</para></listitem> | |
759 | </varlistentry> | |
760 | </variablelist> | |
761 | </refsect1> | |
762 | ||
763 | <refsect1> | |
764 | <title>Environment</title> | |
765 | ||
766 | <variablelist class='environment-variables'> | |
767 | <varlistentry> | |
768 | <term><varname>$SYSTEMD_LOG_LEVEL</varname></term> | |
769 | <listitem><para>systemd reads the log level from this | |
770 | environment variable. This can be overridden with | |
771 | <option>--log-level=</option>.</para></listitem> | |
772 | </varlistentry> | |
773 | ||
774 | <varlistentry> | |
775 | <term><varname>$SYSTEMD_LOG_TARGET</varname></term> | |
776 | <listitem><para>systemd reads the log target from this | |
777 | environment variable. This can be overridden with | |
778 | <option>--log-target=</option>.</para></listitem> | |
779 | </varlistentry> | |
780 | ||
781 | <varlistentry> | |
782 | <term><varname>$SYSTEMD_LOG_COLOR</varname></term> | |
783 | <listitem><para>Controls whether systemd highlights important | |
784 | log messages. This can be overridden with | |
785 | <option>--log-color=</option>.</para></listitem> | |
786 | </varlistentry> | |
787 | ||
788 | <varlistentry> | |
789 | <term><varname>$SYSTEMD_LOG_LOCATION</varname></term> | |
790 | <listitem><para>Controls whether systemd prints the code | |
791 | location along with log messages. This can be overridden with | |
792 | <option>--log-location=</option>.</para></listitem> | |
793 | </varlistentry> | |
794 | ||
795 | <varlistentry> | |
796 | <term><varname>$XDG_CONFIG_HOME</varname></term> | |
797 | <term><varname>$XDG_CONFIG_DIRS</varname></term> | |
798 | <term><varname>$XDG_DATA_HOME</varname></term> | |
799 | <term><varname>$XDG_DATA_DIRS</varname></term> | |
800 | ||
801 | <listitem><para>The systemd user manager uses these variables | |
802 | in accordance to the <ulink | |
803 | url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG | |
804 | Base Directory specification</ulink> to find its | |
805 | configuration.</para></listitem> | |
806 | </varlistentry> | |
807 | ||
808 | <varlistentry> | |
809 | <term><varname>$SYSTEMD_UNIT_PATH</varname></term> | |
810 | ||
811 | <listitem><para>Controls where systemd looks for unit | |
812 | files.</para></listitem> | |
813 | </varlistentry> | |
814 | ||
815 | <varlistentry> | |
816 | <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term> | |
817 | ||
818 | <listitem><para>Controls where systemd looks for SysV init | |
819 | scripts.</para></listitem> | |
820 | </varlistentry> | |
821 | ||
822 | <varlistentry> | |
823 | <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term> | |
824 | ||
825 | <listitem><para>Controls where systemd looks for SysV init | |
826 | script runlevel link farms.</para></listitem> | |
827 | </varlistentry> | |
828 | ||
829 | <varlistentry> | |
830 | <term><varname>$LISTEN_PID</varname></term> | |
831 | <term><varname>$LISTEN_FDS</varname></term> | |
8dd4c05b | 832 | <term><varname>$LISTEN_FDNAMES</varname></term> |
798d3a52 ZJS |
833 | |
834 | <listitem><para>Set by systemd for supervised processes during | |
835 | socket-based activation. See | |
836 | <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
837 | for more information. </para></listitem> | |
838 | </varlistentry> | |
839 | ||
840 | <varlistentry> | |
841 | <term><varname>$NOTIFY_SOCKET</varname></term> | |
842 | ||
843 | <listitem><para>Set by systemd for supervised processes for | |
844 | status and start-up completion notification. See | |
845 | <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
846 | for more information. </para></listitem> | |
847 | </varlistentry> | |
848 | </variablelist> | |
849 | </refsect1> | |
850 | ||
851 | <refsect1> | |
852 | <title>Kernel Command Line</title> | |
853 | ||
854 | <para>When run as system instance systemd parses a number of | |
855 | kernel command line arguments<footnote><para>If run inside a Linux | |
856 | container these arguments may be passed as command line arguments | |
857 | to systemd itself, next to any of the command line options listed | |
858 | in the Options section above. If run outside of Linux containers, | |
859 | these arguments are parsed from <filename>/proc/cmdline</filename> | |
860 | instead.</para></footnote>:</para> | |
861 | ||
862 | <variablelist class='kernel-commandline-options'> | |
863 | <varlistentry> | |
864 | <term><varname>systemd.unit=</varname></term> | |
865 | <term><varname>rd.systemd.unit=</varname></term> | |
866 | ||
867 | <listitem><para>Overrides the unit to activate on boot. | |
868 | Defaults to <filename>default.target</filename>. This may be | |
869 | used to temporarily boot into a different boot unit, for | |
870 | example <filename>rescue.target</filename> or | |
871 | <filename>emergency.service</filename>. See | |
872 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
873 | for details about these units. The option prefixed with | |
874 | <literal>rd.</literal> is honored only in the initial RAM disk | |
875 | (initrd), while the one that is not prefixed only in the main | |
876 | system.</para></listitem> | |
877 | </varlistentry> | |
878 | ||
879 | <varlistentry> | |
880 | <term><varname>systemd.dump_core=</varname></term> | |
881 | ||
882 | <listitem><para>Takes a boolean argument. If | |
b9e74c39 LP |
883 | <option>yes</option>, the systemd manager (PID 1) dumps core |
884 | when it crashes. Otherwise, no core dump is created. Defaults | |
885 | to <option>yes</option>.</para></listitem> | |
886 | </varlistentry> | |
887 | ||
888 | <varlistentry> | |
889 | <term><varname>systemd.crash_chvt=</varname></term> | |
890 | ||
891 | <listitem><para>Takes a positive integer, or a boolean | |
b938cb90 JE |
892 | argument. If a positive integer (in the range 1–63) is |
893 | specified, the system manager (PID 1) will activate the specified | |
b9e74c39 LP |
894 | virtual terminal (VT) when it crashes. Defaults to |
895 | <constant>no</constant>, meaning that no such switch is | |
b938cb90 | 896 | attempted. If set to <constant>yes</constant>, the VT the |
b9e74c39 | 897 | kernel messages are written to is selected.</para></listitem> |
798d3a52 ZJS |
898 | </varlistentry> |
899 | ||
900 | <varlistentry> | |
901 | <term><varname>systemd.crash_shell=</varname></term> | |
902 | ||
903 | <listitem><para>Takes a boolean argument. If | |
b9e74c39 LP |
904 | <option>yes</option>, the system manager (PID 1) spawns a |
905 | shell when it crashes, after a 10s delay. Otherwise, no shell | |
906 | is spawned. Defaults to <option>no</option>, for security | |
907 | reasons, as the shell is not protected by password | |
798d3a52 ZJS |
908 | authentication.</para></listitem> |
909 | </varlistentry> | |
910 | ||
911 | <varlistentry> | |
b9e74c39 | 912 | <term><varname>systemd.crash_reboot=</varname></term> |
798d3a52 | 913 | |
b9e74c39 LP |
914 | <listitem><para>Takes a boolean argument. If |
915 | <option>yes</option>, the system manager (PID 1) will reboot | |
916 | the machine automatically when it crashes, after a 10s delay. | |
917 | Otherwise, the system will hang indefinitely. Defaults to | |
918 | <option>no</option>, in order to avoid a reboot loop. If | |
4cf0b03b MS |
919 | combined with <varname>systemd.crash_shell=</varname>, the |
920 | system is rebooted after the shell exits.</para></listitem> | |
798d3a52 ZJS |
921 | </varlistentry> |
922 | ||
923 | <varlistentry> | |
924 | <term><varname>systemd.confirm_spawn=</varname></term> | |
925 | ||
926 | <listitem><para>Takes a boolean argument. If | |
b9e74c39 LP |
927 | <option>yes</option>, the system manager (PID 1) asks for |
928 | confirmation when spawning processes. Defaults to | |
929 | <option>no</option>.</para></listitem> | |
798d3a52 ZJS |
930 | </varlistentry> |
931 | ||
932 | <varlistentry> | |
933 | <term><varname>systemd.show_status=</varname></term> | |
934 | ||
935 | <listitem><para>Takes a boolean argument or the constant | |
b9e74c39 LP |
936 | <constant>auto</constant>. If <option>yes</option>, the |
937 | systemd manager (PID 1) shows terse service status updates on | |
938 | the console during bootup. <constant>auto</constant> behaves | |
939 | like <option>false</option> until a service fails or there is | |
940 | a significant delay in boot. Defaults to | |
941 | <option>yes</option>, unless <option>quiet</option> is passed | |
b938cb90 | 942 | as kernel command line option, in which case it defaults to |
798d3a52 ZJS |
943 | <constant>auto</constant>.</para></listitem> |
944 | </varlistentry> | |
945 | ||
946 | <varlistentry> | |
947 | <term><varname>systemd.log_target=</varname></term> | |
948 | <term><varname>systemd.log_level=</varname></term> | |
949 | <term><varname>systemd.log_color=</varname></term> | |
950 | <term><varname>systemd.log_location=</varname></term> | |
951 | ||
952 | <listitem><para>Controls log output, with the same effect as | |
953 | the <varname>$SYSTEMD_LOG_TARGET</varname>, | |
954 | <varname>$SYSTEMD_LOG_LEVEL</varname>, | |
955 | <varname>$SYSTEMD_LOG_COLOR</varname>, | |
956 | <varname>$SYSTEMD_LOG_LOCATION</varname> environment variables | |
957 | described above.</para></listitem> | |
958 | </varlistentry> | |
959 | ||
960 | <varlistentry> | |
961 | <term><varname>systemd.default_standard_output=</varname></term> | |
962 | <term><varname>systemd.default_standard_error=</varname></term> | |
963 | <listitem><para>Controls default standard output and error | |
964 | output for services, with the same effect as the | |
965 | <option>--default-standard-output=</option> and | |
966 | <option>--default-standard-error=</option> command line | |
967 | arguments described above, respectively.</para></listitem> | |
968 | </varlistentry> | |
969 | ||
970 | <varlistentry> | |
971 | <term><varname>systemd.setenv=</varname></term> | |
972 | ||
973 | <listitem><para>Takes a string argument in the form | |
974 | VARIABLE=VALUE. May be used to set default environment | |
975 | variables to add to forked child processes. May be used more | |
976 | than once to set multiple variables.</para></listitem> | |
977 | </varlistentry> | |
978 | ||
979 | <varlistentry> | |
980 | <term><varname>quiet</varname></term> | |
981 | ||
982 | <listitem><para>Turn off status output at boot, much like | |
983 | <varname>systemd.show_status=false</varname> would. Note that | |
984 | this option is also read by the kernel itself and disables | |
985 | kernel log output. Passing this option hence turns off the | |
986 | usual output from both the system manager and the kernel. | |
987 | </para></listitem> | |
988 | </varlistentry> | |
989 | ||
990 | <varlistentry> | |
991 | <term><varname>debug</varname></term> | |
992 | ||
993 | <listitem><para>Turn on debugging output. This is equivalent | |
994 | to <varname>systemd.log_level=debug</varname>. Note that this | |
995 | option is also read by the kernel itself and enables kernel | |
996 | debug output. Passing this option hence turns on the debug | |
997 | output from both the system manager and the | |
998 | kernel.</para></listitem> | |
999 | </varlistentry> | |
1000 | ||
1001 | <varlistentry> | |
1002 | <term><varname>emergency</varname></term> | |
1003 | <term><varname>-b</varname></term> | |
1004 | ||
1005 | <listitem><para>Boot into emergency mode. This is equivalent | |
1006 | to <varname>systemd.unit=emergency.target</varname> and | |
1007 | provided for compatibility reasons and to be easier to | |
1008 | type.</para></listitem> | |
1009 | </varlistentry> | |
1010 | ||
1011 | <varlistentry> | |
1012 | <term><varname>rescue</varname></term> | |
1013 | <term><varname>single</varname></term> | |
1014 | <term><varname>s</varname></term> | |
1015 | <term><varname>S</varname></term> | |
1016 | <term><varname>1</varname></term> | |
1017 | ||
1018 | <listitem><para>Boot into rescue mode. This is equivalent to | |
1019 | <varname>systemd.unit=rescue.target</varname> and provided for | |
1020 | compatibility reasons and to be easier to | |
1021 | type.</para></listitem> | |
1022 | </varlistentry> | |
1023 | ||
1024 | <varlistentry> | |
1025 | <term><varname>2</varname></term> | |
1026 | <term><varname>3</varname></term> | |
1027 | <term><varname>4</varname></term> | |
1028 | <term><varname>5</varname></term> | |
1029 | ||
1030 | <listitem><para>Boot into the specified legacy SysV runlevel. | |
1031 | These are equivalent to | |
1032 | <varname>systemd.unit=runlevel2.target</varname>, | |
1033 | <varname>systemd.unit=runlevel3.target</varname>, | |
1034 | <varname>systemd.unit=runlevel4.target</varname>, and | |
1035 | <varname>systemd.unit=runlevel5.target</varname>, | |
1036 | respectively, and provided for compatibility reasons and to be | |
1037 | easier to type.</para></listitem> | |
1038 | </varlistentry> | |
1039 | ||
1040 | <varlistentry> | |
1041 | <term><varname>locale.LANG=</varname></term> | |
1042 | <term><varname>locale.LANGUAGE=</varname></term> | |
1043 | <term><varname>locale.LC_CTYPE=</varname></term> | |
1044 | <term><varname>locale.LC_NUMERIC=</varname></term> | |
1045 | <term><varname>locale.LC_TIME=</varname></term> | |
1046 | <term><varname>locale.LC_COLLATE=</varname></term> | |
1047 | <term><varname>locale.LC_MONETARY=</varname></term> | |
1048 | <term><varname>locale.LC_MESSAGES=</varname></term> | |
1049 | <term><varname>locale.LC_PAPER=</varname></term> | |
1050 | <term><varname>locale.LC_NAME=</varname></term> | |
1051 | <term><varname>locale.LC_ADDRESS=</varname></term> | |
1052 | <term><varname>locale.LC_TELEPHONE=</varname></term> | |
1053 | <term><varname>locale.LC_MEASUREMENT=</varname></term> | |
1054 | <term><varname>locale.LC_IDENTIFICATION=</varname></term> | |
1055 | ||
1056 | <listitem><para>Set the system locale to use. This overrides | |
1057 | the settings in <filename>/etc/locale.conf</filename>. For | |
b938cb90 | 1058 | more information, see |
3ba3a79d | 1059 | <citerefentry project='man-pages'><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
798d3a52 | 1060 | and |
3ba3a79d | 1061 | <citerefentry project='man-pages'><refentrytitle>locale</refentrytitle><manvolnum>7</manvolnum></citerefentry>. |
798d3a52 ZJS |
1062 | </para></listitem> |
1063 | </varlistentry> | |
1064 | </variablelist> | |
1065 | ||
1066 | <para>For other kernel command line parameters understood by | |
1067 | components of the core OS, please refer to | |
1068 | <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> | |
1069 | </refsect1> | |
1070 | ||
1071 | <refsect1> | |
1072 | <title>Sockets and FIFOs</title> | |
1073 | ||
1074 | <variablelist> | |
1075 | <varlistentry> | |
1076 | <term><filename>/run/systemd/notify</filename></term> | |
1077 | ||
1078 | <listitem><para>Daemon status notification socket. This is an | |
1079 | <constant>AF_UNIX</constant> datagram socket and is used to | |
1080 | implement the daemon notification logic as implemented by | |
1081 | <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem> | |
1082 | ||
1083 | </varlistentry> | |
1084 | ||
798d3a52 ZJS |
1085 | <varlistentry> |
1086 | <term><filename>/run/systemd/private</filename></term> | |
1087 | ||
1088 | <listitem><para>Used internally as communication channel | |
1089 | between | |
1090 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
1091 | and the systemd process. This is an | |
1092 | <constant>AF_UNIX</constant> stream socket. This interface is | |
1093 | private to systemd and should not be used in external | |
1094 | projects.</para></listitem> | |
1095 | </varlistentry> | |
1096 | ||
1097 | <varlistentry> | |
1098 | <term><filename>/dev/initctl</filename></term> | |
1099 | ||
1100 | <listitem><para>Limited compatibility support for the SysV | |
1101 | client interface, as implemented by the | |
1102 | <filename>systemd-initctl.service</filename> unit. This is a | |
1103 | named pipe in the file system. This interface is obsolete and | |
1104 | should not be used in new applications.</para></listitem> | |
1105 | </varlistentry> | |
1106 | </variablelist> | |
1107 | </refsect1> | |
1108 | ||
1109 | <refsect1> | |
1110 | <title>See Also</title> | |
1111 | <para> | |
1112 | The <ulink url="http://www.freedesktop.org/wiki/Software/systemd/">systemd Homepage</ulink>, | |
1113 | <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
3ba3a79d | 1114 | <citerefentry project='man-pages'><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, |
798d3a52 ZJS |
1115 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
1116 | <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
1117 | <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
1118 | <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>, | |
1119 | <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>, | |
1120 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
1121 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
1122 | <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
1123 | <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>, | |
1124 | <citerefentry project='man-pages'><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>, | |
1125 | <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
1126 | </para> | |
1127 | </refsect1> | |
9e632bf7 LP |
1128 | |
1129 | </refentry> |