projects / thirdparty / systemd.git / blame
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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 | |
| 5430f7f2 LP |
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 | |
| 9e632bf7 LP |
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 |
| 9e632bf7 LP |
21 | along with systemd; If not, see <http://www.gnu.org/licenses/>. |
| 22 | --> | |
| 23 | ||
| 24 | <refentry id="systemd"> | |
| 25 | ||
| 26 | <refentryinfo> | |
| 27 | <title>systemd</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</refentrytitle> | |
| 160cd5c9 | 42 | <manvolnum>1</manvolnum> |
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43 | </refmeta> |
| 44 | ||
| 45 | <refnamediv> | |
| 46 | <refname>systemd</refname> | |
| 6f6083dc | 47 | <refname>init</refname> |
| af2d49f7 | 48 | <refpurpose>systemd System and Service Manager</refpurpose> |
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49 | </refnamediv> |
| 50 | ||
| 2218198b LP |
51 | <refsynopsisdiv> |
| 52 | <cmdsynopsis> | |
| 160cd5c9 | 53 | <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command> |
| 2218198b LP |
54 | </cmdsynopsis> |
| 55 | <cmdsynopsis> | |
| 160cd5c9 | 56 | <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command> |
| 2218198b LP |
57 | </cmdsynopsis> |
| 58 | </refsynopsisdiv> | |
| 59 | ||
| 9e632bf7 LP |
60 | <refsect1> |
| 61 | <title>Description</title> | |
| 62 | ||
| af2d49f7 | 63 | <para>systemd is a system and service manager for |
| 2218198b | 64 | Linux operating systems. When run as first process on |
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65 | boot (as PID 1), it acts as init system that brings |
| 66 | up and maintains userspace services.</para> | |
| 2218198b | 67 | |
| af62c704 | 68 | <para>For compatibility with SysV, if systemd is called |
| 2218198b | 69 | as <command>init</command> and a PID that is not |
| af62c704 | 70 | 1, it will execute <command>telinit</command> and pass |
| 2218198b LP |
71 | all command line arguments unmodified. That means |
| 72 | <command>init</command> and <command>telinit</command> | |
| 73 | are mostly equivalent when invoked from normal login sessions. See | |
| 74 | <citerefentry><refentrytitle>telinit</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
| 75 | for more information.</para> | |
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76 | |
| 77 | <para>When run as system instance, systemd interprets | |
| 78 | the configuration file | |
| 79 | <filename>system.conf</filename>, otherwise | |
| af2d49f7 | 80 | <filename>user.conf</filename>. See |
| f3e219a2 LP |
81 | <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> |
| 82 | for more information.</para> | |
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83 | </refsect1> |
| 84 | ||
| 85 | <refsect1> | |
| 86 | <title>Options</title> | |
| 87 | ||
| 88 | <para>The following options are understood:</para> | |
| 89 | ||
| 90 | <variablelist> | |
| 91 | <varlistentry> | |
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92 | <term><option>-h</option></term> |
| 93 | <term><option>--help</option></term> | |
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94 | |
| 95 | <listitem><para>Prints a short help | |
| 96 | text and exits.</para></listitem> | |
| 97 | </varlistentry> | |
| f3e219a2 LP |
98 | <varlistentry> |
| 99 | <term><option>--test</option></term> | |
| 100 | ||
| 101 | <listitem><para>Determine startup | |
| 102 | sequence, dump it and exit. This is an | |
| 103 | option useful for debugging | |
| 104 | only.</para></listitem> | |
| 105 | </varlistentry> | |
| 106 | <varlistentry> | |
| 107 | <term><option>--dump-configuration-items</option></term> | |
| 108 | ||
| 109 | <listitem><para>Dump understood unit | |
| 110 | configuration items. This outputs a | |
| 111 | terse but complete list of | |
| 112 | configuration items understood in unit | |
| 113 | definition files.</para></listitem> | |
| 114 | </varlistentry> | |
| 115 | <varlistentry> | |
| 116 | <term><option>--introspect=</option></term> | |
| 117 | ||
| 118 | <listitem><para>Extract D-Bus | |
| 119 | interface introspection data. This is | |
| ad678a06 | 120 | mostly useful at install time |
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121 | to generate data suitable for the |
| 122 | D-Bus interfaces | |
| 123 | repository. Optionally the interface | |
| 124 | name for the introspection data may be | |
| 125 | specified. If omitted, the | |
| 126 | introspection data for all interfaces | |
| 127 | is dumped.</para></listitem> | |
| 128 | </varlistentry> | |
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129 | <varlistentry> |
| 130 | <term><option>--unit=</option></term> | |
| 131 | ||
| 132 | <listitem><para>Set default unit to | |
| 133 | activate on startup. If not specified | |
| 134 | defaults to | |
| 135 | <filename>default.target</filename>.</para></listitem> | |
| 136 | </varlistentry> | |
| 137 | <varlistentry> | |
| edb9aaa8 | 138 | <term><option>--system</option></term> |
| af2d49f7 | 139 | <term><option>--user</option></term> |
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140 | |
| 141 | <listitem><para>Tell systemd to run a | |
| af2d49f7 | 142 | system instance (resp. user |
| edb9aaa8 | 143 | instance), even if the process ID is |
| 248e6030 LP |
144 | not 1 (resp. is 1), i.e. systemd is |
| 145 | not (resp. is) run as init process. | |
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146 | Normally it should not be necessary to |
| 147 | pass these options, as systemd | |
| 148 | automatically detects the mode it is | |
| 149 | started in. These options are hence of | |
| 248e6030 LP |
150 | little use except for debugging. Note |
| 151 | that it is not supported booting and | |
| 152 | maintaining a full system with systemd | |
| 153 | running in <option>--system</option> | |
| 154 | mode, but PID not 1. In practice, | |
| 155 | passing <option>--system</option> explicitly is | |
| 156 | only useful in conjunction with | |
| 157 | <option>--test</option>.</para></listitem> | |
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158 | </varlistentry> |
| 159 | <varlistentry> | |
| f3e219a2 | 160 | <term><option>--dump-core</option></term> |
| 2218198b | 161 | |
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162 | <listitem><para>Dump core on |
| 163 | crash. This switch has no effect when | |
| 164 | run as user | |
| 165 | instance.</para></listitem> | |
| 2218198b LP |
166 | </varlistentry> |
| 167 | <varlistentry> | |
| f3e219a2 | 168 | <term><option>--crash-shell</option></term> |
| 2218198b | 169 | |
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170 | <listitem><para>Run shell on |
| 171 | crash. This switch has no effect when | |
| 172 | run as user | |
| 173 | instance.</para></listitem> | |
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174 | </varlistentry> |
| 175 | <varlistentry> | |
| 176 | <term><option>--confirm-spawn</option></term> | |
| 177 | ||
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178 | <listitem><para>Ask for confirmation |
| 179 | when spawning processes. This switch | |
| 180 | has no effect when run as user | |
| 181 | instance.</para></listitem> | |
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182 | </varlistentry> |
| 183 | <varlistentry> | |
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184 | <term><option>--show-status=</option></term> |
| 185 | ||
| 186 | <listitem><para>Show terse service | |
| 187 | status information while booting. This | |
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188 | switch has no effect when run as user |
| 189 | instance. Takes a boolean argument | |
| 190 | which may be omitted which is | |
| 191 | interpreted as | |
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192 | <option>true</option>.</para></listitem> |
| 193 | </varlistentry> | |
| 194 | <varlistentry> | |
| 195 | <term><option>--sysv-console=</option></term> | |
| 2218198b | 196 | |
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197 | <listitem><para>Controls whether |
| 198 | output of SysV init scripts will be | |
| 199 | directed to the console. This switch | |
| af2d49f7 | 200 | has no effect when run as user |
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201 | instance. Takes a boolean argument |
| 202 | which may be omitted which is | |
| 203 | interpreted as | |
| 204 | <option>true</option>.</para></listitem> | |
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205 | </varlistentry> |
| 206 | <varlistentry> | |
| 207 | <term><option>--log-target=</option></term> | |
| 208 | ||
| 209 | <listitem><para>Set log | |
| 210 | target. Argument must be one of | |
| 211 | <option>console</option>, | |
| 4cfa2c99 | 212 | <option>journal</option>, |
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213 | <option>syslog</option>, |
| 214 | <option>kmsg</option>, | |
| 4cfa2c99 | 215 | <option>journal-or-kmsg</option>, |
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216 | <option>syslog-or-kmsg</option>, |
| 217 | <option>null</option>.</para></listitem> | |
| 2218198b LP |
218 | </varlistentry> |
| 219 | <varlistentry> | |
| 220 | <term><option>--log-level=</option></term> | |
| 221 | ||
| 222 | <listitem><para>Set log level. As | |
| 223 | argument this accepts a numerical log | |
| 224 | level or the well-known <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
| 225 | symbolic names (lowercase): | |
| 226 | <option>emerg</option>, | |
| 227 | <option>alert</option>, | |
| 228 | <option>crit</option>, | |
| 229 | <option>err</option>, | |
| 230 | <option>warning</option>, | |
| 231 | <option>notice</option>, | |
| 232 | <option>info</option>, | |
| 233 | <option>debug</option>.</para></listitem> | |
| 234 | </varlistentry> | |
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235 | <varlistentry> |
| 236 | <term><option>--log-color=</option></term> | |
| 237 | ||
| 238 | <listitem><para>Highlight important | |
| 239 | log messages. Argument is a boolean | |
| 240 | value. If the argument is omitted it | |
| 241 | defaults to | |
| 242 | <option>true</option>.</para></listitem> | |
| 243 | </varlistentry> | |
| 244 | <varlistentry> | |
| 245 | <term><option>--log-location=</option></term> | |
| 246 | ||
| 247 | <listitem><para>Include code location | |
| 248 | in log messages. This is mostly | |
| 249 | relevant for debugging | |
| 250 | purposes. Argument is a boolean | |
| 251 | value. If the argument is omitted | |
| 252 | it defaults to | |
| 253 | <option>true</option>.</para></listitem> | |
| 254 | </varlistentry> | |
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255 | <varlistentry> |
| 256 | <term><option>--default-standard-output=</option></term> | |
| 257 | <term><option>--default-standard-error=</option></term> | |
| 258 | ||
| 259 | <listitem><para>Sets the default | |
| 260 | output resp. error output for all | |
| 261 | services and sockets, i.e. controls | |
| 262 | the default for | |
| 263 | <option>StandardOutput=</option> | |
| 96804f05 | 264 | resp. <option>StandardError=</option> |
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265 | (see |
| 266 | <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> | |
| 267 | for details). Takes one of | |
| 268 | <option>inherit</option>, | |
| 269 | <option>null</option>, | |
| 270 | <option>tty</option>, | |
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271 | <option>journal</option>, |
| 272 | <option>journal+console</option>, | |
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273 | <option>syslog</option>, |
| 274 | <option>syslog+console</option>, | |
| 275 | <option>kmsg</option>, | |
| 756a8d17 | 276 | <option>kmsg+console</option>. If the |
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277 | argument is omitted |
| 278 | <option>--default-standard-output=</option> | |
| 4cfa2c99 | 279 | defaults to <option>journal</option> |
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280 | and |
| 281 | <option>--default-standard-error=</option> | |
| 282 | to | |
| 934da035 | 283 | <option>inherit</option>.</para></listitem> |
| 0a494f1f | 284 | </varlistentry> |
| 2218198b LP |
285 | </variablelist> |
| 286 | </refsect1> | |
| 287 | ||
| 99ffae46 LP |
288 | <refsect1> |
| 289 | <title>Concepts</title> | |
| 290 | ||
| 291 | <para>systemd provides a dependency system between | |
| 292 | various entities called "units". Units encapsulate | |
| 293 | various objects that are relevant for system boot-up | |
| 5632e374 | 294 | and maintenance. The majority of units are configured |
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295 | in unit configuration files, whose syntax and basic |
| 296 | set of options is described in | |
| 297 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
| 298 | however some are created automatically from other | |
| 299 | configuration or dynamically from system state. Units | |
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300 | may be 'active' (meaning started, bound, plugged in, |
| 301 | ... depending on the unit type, see below), or | |
| 302 | 'inactive' (meaning stopped, unbound, unplugged, ...), | |
| 303 | as well as in the process of being activated or | |
| 304 | deactivated, i.e. between the two states (these states | |
| 305 | are called 'activating', 'deactivating'). A special | |
| 74ac3cbd | 306 | 'failed' state is available as well which is very |
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307 | similar to 'inactive' and is entered when the service |
| 308 | failed in some way (process returned error code on | |
| 309 | exit, or crashed, or an operation timed out). If this | |
| 310 | state is entered the cause will be logged, for later | |
| 311 | reference. Note that the various unit types may have a | |
| 312 | number of additional substates, which are mapped to | |
| 313 | the five generalized unit states described | |
| 314 | here.</para> | |
| 315 | ||
| 316 | <para>The following unit types are available:</para> | |
| 99ffae46 LP |
317 | |
| 318 | <orderedlist> | |
| 319 | <listitem><para>Service units, which control | |
| 320 | daemons and the processes they consist of. For | |
| 321 | details see | |
| 322 | <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 323 | ||
| 324 | <listitem><para>Socket units, which | |
| 325 | encapsulate local IPC or network sockets in | |
| 326 | the system, useful for socket-based | |
| 327 | activation. For details about socket units see | |
| 328 | <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
| 329 | for details on socket-based activation and | |
| 330 | other forms of activation, see | |
| 331 | <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem> | |
| 332 | ||
| 333 | <listitem><para>Target units are useful to | |
| 334 | group units, or provide well-known | |
| 335 | synchronization points during boot-up, see | |
| 336 | <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 337 | ||
| 338 | <listitem><para>Device units expose kernel | |
| 339 | devices in systemd and may be used to | |
| 340 | implement device-based activation. For details | |
| 341 | see | |
| 342 | <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 343 | ||
| 344 | <listitem><para>Mount units control mount | |
| 345 | points in the file system, for details see | |
| 346 | <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 347 | ||
| 348 | <listitem><para>Automount units provide | |
| 349 | automount capabilities, for on-demand mounting | |
| 350 | of file systems as well as parallelized | |
| 351 | boot-up. See | |
| 352 | <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 353 | ||
| 354 | <listitem><para>Snapshot units can be used to | |
| 355 | temporarily save the state of the set of | |
| 356 | systemd units, which later may be restored by | |
| 357 | activating the saved snapshot unit. For more | |
| 358 | information see | |
| 7461d1b7 | 359 | <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| 99ffae46 LP |
360 | |
| 361 | <listitem><para>Timer units are useful for | |
| 362 | triggering activation of other units based on | |
| 363 | timers. You may find details in | |
| 364 | <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 365 | ||
| 366 | <listitem><para>Swap units are very similar to | |
| f8553ccb | 367 | mount units and encapsulate memory swap |
| 99ffae46 | 368 | partitions or files of the operating |
| f8553ccb | 369 | system. They are described in <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> |
| 99ffae46 LP |
370 | |
| 371 | <listitem><para>Path units may be used | |
| dccb2600 | 372 | to activate other services when file system |
| 99ffae46 LP |
373 | objects change or are modified. See |
| 374 | <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> | |
| 375 | ||
| 376 | </orderedlist> | |
| 377 | ||
| 378 | <para>Units are named as their configuration | |
| 379 | files. Some units have special semantics. A detailed | |
| f8553ccb | 380 | list is available in |
| 99ffae46 LP |
381 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> |
| 382 | ||
| b9975629 LP |
383 | <para>systemd knows various kinds of dependencies, |
| 384 | including positive and negative requirement | |
| 385 | dependencies (i.e. <varname>Requires=</varname> and | |
| 386 | <varname>Conflicts=</varname>) as well as ordering | |
| 387 | dependencies (<varname>After=</varname> and | |
| 388 | <varname>Before=</varname>). NB: ordering and | |
| 389 | requirement dependencies are orthogonal. If only a | |
| 390 | requirement dependency exists between two units | |
| 391 | (e.g. <filename>foo.service</filename> requires | |
| 392 | <filename>bar.service</filename>), but no ordering | |
| 393 | dependency (e.g. <filename>foo.service</filename> | |
| 394 | after <filename>bar.service</filename>) and both are | |
| 395 | requested to start, they will be started in | |
| 396 | parallel. It is a common pattern that both requirement | |
| 397 | and ordering dependencies are placed between two | |
| 398 | units. Also note that the majority of dependencies are | |
| 399 | implicitly created and maintained by systemd. In most | |
| 400 | cases it should be unnecessary to declare additional | |
| 401 | dependencies manually, however it is possible to do | |
| 402 | this.</para> | |
| 403 | ||
| 404 | <para>Application programs and units (via | |
| f8553ccb | 405 | dependencies) may request state changes of units. In |
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406 | systemd, these requests are encapsulated as 'jobs' and |
| 407 | maintained in a job queue. Jobs may succeed or can | |
| 408 | fail, their execution is ordered based on the ordering | |
| 409 | dependencies of the units they have been scheduled | |
| 410 | for.</para> | |
| 411 | ||
| 99ffae46 | 412 | <para>On boot systemd activates the target unit |
| dccb2600 | 413 | <filename>default.target</filename> whose job is to |
| 99ffae46 LP |
414 | activate on-boot services and other on-boot units by |
| 415 | pulling them in via dependencies. Usually the unit | |
| 416 | name is just an alias (symlink) for either | |
| 417 | <filename>graphical.target</filename> (for | |
| 418 | fully-featured boots into the UI) or | |
| 419 | <filename>multi-user.target</filename> (for limited | |
| 420 | console-only boots for use in embedded or server | |
| 421 | environments, or similar; a subset of | |
| 422 | graphical.target). However it is at the discretion of | |
| 423 | the administrator to configure it as an alias to any | |
| 424 | other target unit. See | |
| 425 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
| 426 | for details about these target units.</para> | |
| 427 | ||
| dccb2600 | 428 | <para>Processes systemd spawns are placed in |
| 59a3e1bc LP |
429 | individual Linux control groups named after the unit |
| 430 | which they belong to in the private systemd | |
| 431 | hierarchy. (see <ulink | |
| 432 | url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink> | |
| 433 | for more information about control groups, or short | |
| 434 | "cgroups"). systemd uses this to effectively keep | |
| 435 | track of processes. Control group information is | |
| 436 | maintained in the kernel, and is accessible via the | |
| 437 | file system hierarchy (beneath | |
| 77d5f105 | 438 | <filename>/sys/fs/cgroup/systemd/</filename>), or in tools |
| 59a3e1bc LP |
439 | such as |
| 440 | <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
| 441 | (<command>ps xawf -eo pid,user,cgroup,args</command> | |
| 442 | is particularly useful to list all processes and the | |
| 443 | systemd units they belong to.).</para> | |
| 444 | ||
| 445 | <para>systemd is compatible with the SysV init system | |
| 446 | to a large degree: SysV init scripts are supported and | |
| 447 | simply read as an alternative (though limited) | |
| 448 | configuration file format. The SysV | |
| 449 | <filename>/dev/initctl</filename> interface is | |
| dccb2600 OÇ |
450 | provided, and compatibility implementations of the |
| 451 | various SysV client tools are available. In addition to | |
| 452 | that, various established Unix functionality such as | |
| 59a3e1bc LP |
453 | <filename>/etc/fstab</filename> or the |
| 454 | <filename>utmp</filename> database are | |
| 455 | supported.</para> | |
| 456 | ||
| 457 | <para>systemd has a minimal transaction system: if a | |
| 458 | unit is requested to start up or shut down it will add | |
| 459 | it and all its dependencies to a temporary | |
| 460 | transaction. Then, it will verify if the transaction | |
| 461 | is consistent (i.e. whether the ordering of all units | |
| 462 | is cycle-free). If it is not, systemd will try to fix | |
| 463 | it up, and removes non-essential jobs from the | |
| 464 | transaction that might remove the loop. Also, systemd | |
| 465 | tries to suppress non-essential jobs in the | |
| 466 | transaction that would stop a running service. Finally | |
| 467 | it is checked whether the jobs of the transaction | |
| 468 | contradict jobs that have already been queued, and | |
| 469 | optionally the transaction is aborted then. If all | |
| 470 | worked out and the transaction is consistent and | |
| 471 | minimized in its impact it is merged with all already | |
| 472 | outstanding jobs and added to the run | |
| 473 | queue. Effectively this means that before executing a | |
| 474 | requested operation, systemd will verify that it makes | |
| 475 | sense, fixing it if possible, and only failing if it | |
| 476 | really cannot work.</para> | |
| 477 | ||
| 478 | <para>Systemd contains native implementations of | |
| 479 | various tasks that need to be executed as part of the | |
| 480 | boot process. For example, it sets the host name or | |
| 481 | configures the loopback network device. It also sets | |
| 482 | up and mounts various API file systems, such as | |
| 483 | <filename>/sys</filename> or | |
| 484 | <filename>/proc</filename>.</para> | |
| 485 | ||
| 99ffae46 LP |
486 | <para>For more information about the concepts and |
| 487 | ideas behind systemd please refer to the <ulink | |
| 488 | url="http://0pointer.de/blog/projects/systemd.html">Original | |
| 59a3e1bc | 489 | Design Document</ulink>.</para> |
| b9aea954 LP |
490 | |
| 491 | <para>Note that some but not all interfaces provided | |
| 492 | by systemd are covered by the <ulink | |
| 493 | url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface | |
| 494 | Stability Promise</ulink>.</para> | |
| 99ffae46 LP |
495 | </refsect1> |
| 496 | ||
| 160cd5c9 LP |
497 | <refsect1> |
| 498 | <title>Directories</title> | |
| 7874bcd6 LP |
499 | |
| 500 | <variablelist> | |
| 501 | <varlistentry> | |
| 502 | <term>System unit directories</term> | |
| 503 | ||
| 504 | <listitem><para>The systemd system | |
| 505 | manager reads unit configuration from | |
| 506 | various directories. Packages that | |
| 507 | want to install unit files shall place | |
| 508 | them in the directory returned by | |
| 509 | <command>pkg-config systemd | |
| 510 | --variable=systemdsystemunitdir</command>. Other | |
| 511 | directories checked are | |
| d636fa3d | 512 | <filename>/usr/local/lib/systemd/system</filename> |
| 7874bcd6 | 513 | and |
| d636fa3d | 514 | <filename>/usr/lib/systemd/system</filename>. User |
| 7874bcd6 LP |
515 | configuration always takes |
| 516 | precedence. <command>pkg-config | |
| 517 | systemd | |
| 518 | --variable=systemdsystemconfdir</command> | |
| 519 | returns the path of the system | |
| 520 | configuration directory. Packages | |
| ee5762e3 LP |
521 | should alter the content of these |
| 522 | directories only with the | |
| 523 | <command>enable</command> and | |
| 524 | <command>disable</command> commands of | |
| 525 | the | |
| 526 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
| 7874bcd6 LP |
527 | tool.</para></listitem> |
| 528 | </varlistentry> | |
| 529 | </variablelist> | |
| 530 | ||
| 531 | <variablelist> | |
| 532 | <varlistentry> | |
| af2d49f7 | 533 | <term>User unit directories</term> |
| 7874bcd6 LP |
534 | |
| 535 | <listitem><para>Similar rules apply | |
| af2d49f7 | 536 | for the user unit |
| 7874bcd6 LP |
537 | directories. However, here the <ulink |
| 538 | url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG | |
| 539 | Base Directory specification</ulink> | |
| 540 | is followed to find | |
| 541 | units. Applications should place their | |
| 542 | unit files in the directory returned | |
| 543 | by <command>pkg-config systemd | |
| af2d49f7 | 544 | --variable=systemduserunitdir</command>. Global |
| ee5762e3 LP |
545 | configuration is done in the directory |
| 546 | reported by <command>pkg-config | |
| 547 | systemd | |
| af2d49f7 | 548 | --variable=systemduserconfdir</command>. The |
| ee5762e3 LP |
549 | <command>enable</command> and |
| 550 | <command>disable</command> commands of | |
| 551 | the | |
| 552 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
| 7874bcd6 LP |
553 | tool can handle both global (i.e. for |
| 554 | all users) and private (for one user) | |
| 555 | enabling/disabling of | |
| 556 | units.</para></listitem> | |
| 557 | </varlistentry> | |
| 558 | </variablelist> | |
| 559 | ||
| 560 | <variablelist> | |
| 561 | <varlistentry> | |
| 562 | <term>SysV init scripts directory</term> | |
| 563 | ||
| 564 | <listitem><para>The location of the | |
| 565 | SysV init script directory varies | |
| 566 | between distributions. If systemd | |
| 567 | cannot find a native unit file for a | |
| af62c704 | 568 | requested service, it will look for a |
| 7874bcd6 LP |
569 | SysV init script of the same name |
| 570 | (with the | |
| 571 | <filename>.service</filename> suffix | |
| 572 | removed).</para></listitem> | |
| 573 | </varlistentry> | |
| 574 | </variablelist> | |
| 575 | ||
| 576 | <variablelist> | |
| 577 | <varlistentry> | |
| 578 | <term>SysV runlevel link farm directory</term> | |
| 579 | ||
| 580 | <listitem><para>The location of the | |
| 581 | SysV runlevel link farm directory | |
| 582 | varies between distributions. systemd | |
| 583 | will take the link farm into account | |
| 584 | when figuring out whether a service | |
| 585 | shall be enabled. Note that a service | |
| 586 | unit with a native unit configuration | |
| edb9aaa8 | 587 | file cannot be started by activating it |
| 7874bcd6 LP |
588 | in the SysV runlevel link |
| 589 | farm.</para></listitem> | |
| 590 | </varlistentry> | |
| 591 | </variablelist> | |
| 160cd5c9 LP |
592 | </refsect1> |
| 593 | ||
| 594 | <refsect1> | |
| 7874bcd6 | 595 | <title>Signals</title> |
| 160cd5c9 LP |
596 | |
| 597 | <variablelist> | |
| 598 | <varlistentry> | |
| 7874bcd6 LP |
599 | <term>SIGTERM</term> |
| 600 | ||
| 601 | <listitem><para>Upon receiving this | |
| 602 | signal the systemd system manager | |
| 603 | serializes its state, reexecutes | |
| 604 | itself and deserializes the saved | |
| 605 | state again. This is mostly equivalent | |
| 606 | to <command>systemctl | |
| 607 | daemon-reexec</command>.</para> | |
| 608 | ||
| af2d49f7 | 609 | <para>systemd user managers will |
| 7874bcd6 LP |
610 | start the |
| 611 | <filename>exit.target</filename> unit | |
| 612 | when this signal is received. This is | |
| 613 | mostly equivalent to | |
| af2d49f7 | 614 | <command>systemctl --user start |
| 7874bcd6 LP |
615 | exit.target</command>.</para></listitem> |
| 616 | </varlistentry> | |
| 617 | ||
| 618 | <varlistentry> | |
| 619 | <term>SIGINT</term> | |
| 620 | ||
| 621 | <listitem><para>Upon receiving this | |
| 622 | signal the systemd system manager will | |
| 623 | start the | |
| 624 | <filename>ctrl-alt-del.target</filename> unit. This | |
| 625 | is mostly equivalent to | |
| 626 | <command>systemctl start | |
| 627 | ctl-alt-del.target</command>.</para> | |
| 628 | ||
| af2d49f7 | 629 | <para>systemd user managers |
| 7874bcd6 LP |
630 | treat this signal the same way as |
| 631 | SIGTERM.</para></listitem> | |
| 632 | </varlistentry> | |
| 633 | ||
| 634 | <varlistentry> | |
| 635 | <term>SIGWINCH</term> | |
| 636 | ||
| 637 | <listitem><para>When this signal is | |
| 638 | received the systemd system manager | |
| 639 | will start the | |
| 640 | <filename>kbrequest.target</filename> | |
| 641 | unit. This is mostly equivalent to | |
| 642 | <command>systemctl start | |
| 643 | kbrequest.target</command>.</para> | |
| 644 | ||
| 645 | <para>This signal is ignored by | |
| af2d49f7 | 646 | systemd user |
| 7874bcd6 LP |
647 | managers.</para></listitem> |
| 648 | </varlistentry> | |
| 649 | ||
| 650 | <varlistentry> | |
| 651 | <term>SIGPWR</term> | |
| 652 | ||
| 653 | <listitem><para>When this signal is | |
| 654 | received the systemd manager | |
| 655 | will start the | |
| 656 | <filename>sigpwr.target</filename> | |
| 657 | unit. This is mostly equivalent to | |
| 658 | <command>systemctl start | |
| 659 | sigpwr.target</command>.</para></listitem> | |
| 660 | </varlistentry> | |
| 661 | ||
| 662 | <varlistentry> | |
| 663 | <term>SIGUSR1</term> | |
| 664 | ||
| 665 | <listitem><para>When this signal is | |
| 666 | received the systemd manager will try | |
| 667 | to reconnect to the D-Bus | |
| 668 | bus.</para></listitem> | |
| 669 | </varlistentry> | |
| 670 | ||
| 671 | <varlistentry> | |
| 672 | <term>SIGUSR2</term> | |
| 673 | ||
| 674 | <listitem><para>When this signal is | |
| 675 | received the systemd manager will log | |
| 676 | its complete state in human readable | |
| 677 | form. The data logged is the same as | |
| 678 | printed by <command>systemctl | |
| 679 | dump</command>.</para></listitem> | |
| 680 | </varlistentry> | |
| 681 | ||
| 682 | <varlistentry> | |
| 683 | <term>SIGHUP</term> | |
| 684 | ||
| 685 | <listitem><para>Reloads the complete | |
| 686 | daemon configuration. This is mostly | |
| 687 | equivalent to <command>systemctl | |
| 688 | daemon-reload</command>.</para></listitem> | |
| 689 | </varlistentry> | |
| 690 | ||
| 691 | <varlistentry> | |
| 692 | <term>SIGRTMIN+0</term> | |
| 693 | ||
| 694 | <listitem><para>Enters default mode, starts the | |
| 695 | <filename>default.target</filename> | |
| 696 | unit. This is mostly equivalent to | |
| 697 | <command>systemctl start | |
| 698 | default.target</command>.</para></listitem> | |
| 699 | </varlistentry> | |
| 700 | ||
| 701 | <varlistentry> | |
| 702 | <term>SIGRTMIN+1</term> | |
| 703 | ||
| 704 | <listitem><para>Enters rescue mode, | |
| 705 | starts the | |
| 706 | <filename>rescue.target</filename> | |
| 707 | unit. This is mostly equivalent to | |
| 708 | <command>systemctl isolate | |
| 709 | rescue.target</command>.</para></listitem> | |
| 710 | </varlistentry> | |
| 160cd5c9 | 711 | |
| 7874bcd6 LP |
712 | <varlistentry> |
| 713 | <term>SIGRTMIN+2</term> | |
| 714 | ||
| 715 | <listitem><para>Enters emergency mode, | |
| 716 | starts the | |
| 717 | <filename>emergency.service</filename> | |
| 718 | unit. This is mostly equivalent to | |
| 719 | <command>systemctl isolate | |
| 720 | emergency.service</command>.</para></listitem> | |
| 721 | </varlistentry> | |
| 722 | ||
| 723 | <varlistentry> | |
| 724 | <term>SIGRTMIN+3</term> | |
| 725 | ||
| 726 | <listitem><para>Halts the machine, | |
| 727 | starts the | |
| 728 | <filename>halt.target</filename> | |
| 729 | unit. This is mostly equivalent to | |
| 730 | <command>systemctl start | |
| 731 | halt.target</command>.</para></listitem> | |
| 732 | </varlistentry> | |
| 733 | ||
| 734 | <varlistentry> | |
| 735 | <term>SIGRTMIN+4</term> | |
| 736 | ||
| 737 | <listitem><para>Powers off the machine, | |
| 738 | starts the | |
| 739 | <filename>poweroff.target</filename> | |
| 740 | unit. This is mostly equivalent to | |
| 741 | <command>systemctl start | |
| 742 | poweroff.target</command>.</para></listitem> | |
| 743 | </varlistentry> | |
| 744 | ||
| 745 | <varlistentry> | |
| 746 | <term>SIGRTMIN+5</term> | |
| 747 | ||
| 748 | <listitem><para>Reboots the machine, | |
| 749 | starts the | |
| 750 | <filename>reboot.target</filename> | |
| 751 | unit. This is mostly equivalent to | |
| 752 | <command>systemctl start | |
| 753 | reboot.target</command>.</para></listitem> | |
| 160cd5c9 | 754 | </varlistentry> |
| 0658666b LP |
755 | |
| 756 | <varlistentry> | |
| 757 | <term>SIGRTMIN+6</term> | |
| 758 | ||
| 759 | <listitem><para>Reboots the machine via kexec, | |
| 760 | starts the | |
| 761 | <filename>kexec.target</filename> | |
| 762 | unit. This is mostly equivalent to | |
| 763 | <command>systemctl start | |
| 764 | kexec.target</command>.</para></listitem> | |
| 765 | </varlistentry> | |
| 766 | ||
| 767 | <varlistentry> | |
| 768 | <term>SIGRTMIN+13</term> | |
| 769 | ||
| 770 | <listitem><para>Immediately halts the machine.</para></listitem> | |
| 771 | </varlistentry> | |
| 772 | ||
| 773 | <varlistentry> | |
| 774 | <term>SIGRTMIN+14</term> | |
| 775 | ||
| 776 | <listitem><para>Immediately powers off the machine.</para></listitem> | |
| 777 | </varlistentry> | |
| 778 | ||
| 779 | <varlistentry> | |
| 780 | <term>SIGRTMIN+15</term> | |
| 781 | ||
| 782 | <listitem><para>Immediately reboots the machine.</para></listitem> | |
| 783 | </varlistentry> | |
| 784 | ||
| 785 | <varlistentry> | |
| 786 | <term>SIGRTMIN+16</term> | |
| 787 | ||
| 788 | <listitem><para>Immediately reboots the machine with kexec.</para></listitem> | |
| 789 | </varlistentry> | |
| 790 | ||
| 791 | <varlistentry> | |
| 792 | <term>SIGRTMIN+20</term> | |
| 793 | ||
| 794 | <listitem><para>Enables display of | |
| 795 | status messages on the console, as | |
| 796 | controlled via | |
| 797 | <varname>systemd.show_status=1</varname> | |
| 798 | on the kernel command | |
| 799 | line.</para></listitem> | |
| 800 | </varlistentry> | |
| 801 | ||
| 802 | <varlistentry> | |
| 803 | <term>SIGRTMIN+21</term> | |
| 804 | ||
| 805 | <listitem><para>Disables display of | |
| 806 | status messages on the console, as | |
| 807 | controlled via | |
| 808 | <varname>systemd.show_status=0</varname> | |
| 809 | on the kernel command | |
| 810 | line.</para></listitem> | |
| 811 | </varlistentry> | |
| 253ee27a LP |
812 | |
| 813 | <varlistentry> | |
| 814 | <term>SIGRTMIN+22</term> | |
| 815 | <term>SIGRTMIN+23</term> | |
| 816 | ||
| 817 | <listitem><para>Sets the log level to | |
| 818 | <literal>debug</literal> | |
| 819 | (resp. <literal>info</literal> on | |
| 75c982a7 | 820 | <literal>SIGRTMIN+23</literal>), as |
| 253ee27a LP |
821 | controlled via |
| 822 | <varname>systemd.log_level=debug</varname> | |
| 823 | (resp. <varname>systemd.log_level=info</varname> | |
| 824 | on <literal>SIGRTMIN+23</literal>) on | |
| 825 | the kernel command | |
| 826 | line.</para></listitem> | |
| 827 | </varlistentry> | |
| 828 | ||
| 829 | <varlistentry> | |
| 4cfa2c99 | 830 | <term>SIGRTMIN+26</term> |
| 253ee27a LP |
831 | <term>SIGRTMIN+27</term> |
| 832 | <term>SIGRTMIN+28</term> | |
| 833 | <term>SIGRTMIN+29</term> | |
| 834 | ||
| 835 | <listitem><para>Sets the log level to | |
| 4cfa2c99 LP |
836 | <literal>journal-or-kmsg</literal> |
| 837 | (resp. <literal>console</literal> on | |
| 838 | <literal>SIGRTMIN+27</literal>; | |
| 839 | resp. <literal>kmsg</literal> on | |
| 253ee27a | 840 | <literal>SIGRTMIN+28</literal>; |
| 34c4b47b | 841 | resp. <literal>syslog-or-kmsg</literal> |
| 253ee27a LP |
842 | on <literal>SIGRTMIN+29</literal>), as |
| 843 | controlled via | |
| 4cfa2c99 LP |
844 | <varname>systemd.log_target=journal-or-kmsg</varname> |
| 845 | (resp. <varname>systemd.log_target=console</varname> | |
| 846 | on <literal>SIGRTMIN+27</literal>; | |
| 847 | resp. <varname>systemd.log_target=kmsg</varname> | |
| 253ee27a LP |
848 | on <literal>SIGRTMIN+28</literal>; |
| 849 | resp | |
| 850 | <varname>systemd.log_target=syslog-or-kmsg</varname> | |
| 851 | on <literal>SIGRTMIN+29</literal>) on | |
| 852 | the kernel command | |
| 853 | line.</para></listitem> | |
| 854 | </varlistentry> | |
| 160cd5c9 LP |
855 | </variablelist> |
| 856 | </refsect1> | |
| 857 | ||
| 7874bcd6 LP |
858 | <refsect1> |
| 859 | <title>Environment</title> | |
| 860 | ||
| 861 | <variablelist> | |
| 862 | <varlistentry> | |
| 863 | <term><varname>$SYSTEMD_LOG_LEVEL</varname></term> | |
| 864 | <listitem><para>systemd reads the | |
| 865 | log level from this environment | |
| 436c44a5 | 866 | variable. This can be overridden with |
| 7874bcd6 LP |
867 | <option>--log-level=</option>.</para></listitem> |
| 868 | </varlistentry> | |
| 869 | ||
| 870 | <varlistentry> | |
| 871 | <term><varname>$SYSTEMD_LOG_TARGET</varname></term> | |
| 872 | <listitem><para>systemd reads the | |
| 873 | log target from this environment | |
| 436c44a5 | 874 | variable. This can be overridden with |
| 7874bcd6 LP |
875 | <option>--log-target=</option>.</para></listitem> |
| 876 | </varlistentry> | |
| 877 | ||
| 878 | <varlistentry> | |
| 879 | <term><varname>$SYSTEMD_LOG_COLOR</varname></term> | |
| 880 | <listitem><para>Controls whether | |
| 881 | systemd highlights important log | |
| 436c44a5 | 882 | messages. This can be overridden with |
| 7874bcd6 LP |
883 | <option>--log-color=</option>.</para></listitem> |
| 884 | </varlistentry> | |
| 885 | ||
| 886 | <varlistentry> | |
| 887 | <term><varname>$SYSTEMD_LOG_LOCATION</varname></term> | |
| 888 | <listitem><para>Controls whether | |
| 889 | systemd prints the code location along | |
| 890 | with log messages. This can be | |
| 436c44a5 | 891 | overridden with |
| 7874bcd6 LP |
892 | <option>--log-location=</option>.</para></listitem> |
| 893 | </varlistentry> | |
| 894 | ||
| 895 | <varlistentry> | |
| 896 | <term><varname>$XDG_CONFIG_HOME</varname></term> | |
| 897 | <term><varname>$XDG_CONFIG_DIRS</varname></term> | |
| 898 | <term><varname>$XDG_DATA_HOME</varname></term> | |
| 899 | <term><varname>$XDG_DATA_DIRS</varname></term> | |
| 900 | ||
| af2d49f7 | 901 | <listitem><para>The systemd user |
| 7874bcd6 LP |
902 | manager uses these variables in |
| 903 | accordance to the <ulink | |
| 904 | url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG | |
| 905 | Base Directory specification</ulink> | |
| 906 | to find its configuration.</para></listitem> | |
| 907 | </varlistentry> | |
| 908 | ||
| 909 | <varlistentry> | |
| 910 | <term><varname>$SYSTEMD_UNIT_PATH</varname></term> | |
| 911 | ||
| 912 | <listitem><para>Controls where systemd | |
| 913 | looks for unit | |
| 914 | files.</para></listitem> | |
| 915 | </varlistentry> | |
| 916 | ||
| 917 | <varlistentry> | |
| 918 | <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term> | |
| 919 | ||
| 920 | <listitem><para>Controls where systemd | |
| 921 | looks for SysV init scripts.</para></listitem> | |
| 922 | </varlistentry> | |
| 923 | ||
| 924 | <varlistentry> | |
| 925 | <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term> | |
| 926 | ||
| 927 | <listitem><para>Controls where systemd | |
| 928 | looks for SysV init script runlevel link | |
| 929 | farms.</para></listitem> | |
| 930 | </varlistentry> | |
| 931 | ||
| 932 | <varlistentry> | |
| 933 | <term><varname>$LISTEN_PID</varname></term> | |
| 934 | <term><varname>$LISTEN_FDS</varname></term> | |
| 935 | ||
| 936 | <listitem><para>Set by systemd for | |
| 937 | supervised processes during | |
| 938 | socket-based activation. See | |
| 939 | <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
| 940 | for more information. | |
| 941 | </para></listitem> | |
| 942 | </varlistentry> | |
| 943 | ||
| 944 | <varlistentry> | |
| 945 | <term><varname>$NOTIFY_SOCKET</varname></term> | |
| 946 | ||
| 947 | <listitem><para>Set by systemd for | |
| 948 | supervised processes for status and | |
| 949 | start-up completion notification. See | |
| 950 | <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry> | |
| 951 | for more information. | |
| 952 | </para></listitem> | |
| 953 | </varlistentry> | |
| 954 | </variablelist> | |
| 955 | </refsect1> | |
| 160cd5c9 | 956 | |
| f3e219a2 LP |
957 | <refsect1> |
| 958 | <title>Kernel Command Line</title> | |
| 959 | ||
| 45dc3a04 LP |
960 | <para>When run as system instance systemd parses a |
| 961 | number of kernel command line | |
| 962 | arguments<footnote><para>If run inside a Linux | |
| 963 | container these arguments may be passed as command | |
| 964 | line arguments to systemd itself, next to any of the | |
| 965 | command line options listed in the Options section | |
| 966 | above. If run outside of Linux containers, these | |
| 967 | arguments are parsed from | |
| 968 | <filename>/proc/cmdline</filename> | |
| 969 | instead.</para></footnote>:</para> | |
| f3e219a2 LP |
970 | |
| 971 | <variablelist> | |
| 972 | <varlistentry> | |
| 973 | <term><varname>systemd.unit=</varname></term> | |
| 974 | ||
| 975 | <listitem><para>Overrides the unit to | |
| 976 | activate on boot. Defaults to | |
| 977 | <filename>default.target</filename>. This | |
| 978 | may be used to temporarily boot into a | |
| 979 | different boot unit, for example | |
| 980 | <filename>rescue.target</filename> or | |
| 981 | <filename>emergency.service</filename>. See | |
| 982 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> | |
| 983 | for details about these | |
| 984 | units.</para></listitem> | |
| 985 | </varlistentry> | |
| 986 | ||
| f3e219a2 LP |
987 | <varlistentry> |
| 988 | <term><varname>systemd.dump_core=</varname></term> | |
| 989 | ||
| 990 | <listitem><para>Takes a boolean | |
| 991 | argument. If <option>true</option> | |
| 992 | systemd dumps core when it | |
| 993 | crashes. Otherwise no core dump is | |
| 994 | created. Defaults to | |
| 995 | <option>true</option>.</para></listitem> | |
| 996 | </varlistentry> | |
| 997 | ||
| 998 | <varlistentry> | |
| 999 | <term><varname>systemd.crash_shell=</varname></term> | |
| 1000 | ||
| 1001 | <listitem><para>Takes a boolean | |
| 1002 | argument. If <option>true</option> | |
| 1003 | systemd spawns a shell when it | |
| f8553ccb AE |
1004 | crashes. Otherwise no shell is |
| 1005 | spawned. Defaults to | |
| f3e219a2 LP |
1006 | <option>false</option>, for security |
| 1007 | reasons, as the shell is not protected | |
| 1008 | by any password | |
| 1009 | authentication.</para></listitem> | |
| 1010 | </varlistentry> | |
| 1011 | ||
| 1012 | <varlistentry> | |
| 1013 | <term><varname>systemd.crash_chvt=</varname></term> | |
| 1014 | ||
| 1015 | <listitem><para>Takes an integer | |
| 1016 | argument. If positive systemd | |
| 1017 | activates the specified virtual | |
| 1018 | terminal when it crashes. Defaults to | |
| 1019 | <literal>-1</literal>.</para></listitem> | |
| 1020 | </varlistentry> | |
| 1021 | ||
| 69dd2852 LP |
1022 | <varlistentry> |
| 1023 | <term><varname>systemd.confirm_spawn=</varname></term> | |
| 1024 | ||
| 1025 | <listitem><para>Takes a boolean | |
| 1026 | argument. If <option>true</option> | |
| 1027 | asks for confirmation when spawning | |
| 1028 | processes. Defaults to | |
| 1029 | <option>false</option>.</para></listitem> | |
| 1030 | </varlistentry> | |
| 1031 | ||
| f3e219a2 LP |
1032 | <varlistentry> |
| 1033 | <term><varname>systemd.show_status=</varname></term> | |
| 1034 | ||
| 1035 | <listitem><para>Takes a boolean | |
| 1036 | argument. If <option>true</option> | |
| 1037 | shows terse service status updates on | |
| 1038 | the console during bootup. Defaults to | |
| 1039 | <option>true</option>.</para></listitem> | |
| 1040 | </varlistentry> | |
| 1041 | ||
| 69dd2852 LP |
1042 | <varlistentry> |
| 1043 | <term><varname>systemd.sysv_console=</varname></term> | |
| 1044 | ||
| 1045 | <listitem><para>Takes a boolean | |
| 1046 | argument. If <option>true</option> | |
| 1047 | output of SysV init scripts will be | |
| 1048 | directed to the console. Defaults to | |
| 1049 | <option>true</option>, unless | |
| 1050 | <option>quiet</option> is passed as | |
| 1051 | kernel command line option in which | |
| 1052 | case it defaults to | |
| 1053 | <option>false</option>.</para></listitem> | |
| 1054 | </varlistentry> | |
| 1055 | ||
| 1056 | <varlistentry> | |
| 1057 | <term><varname>systemd.log_target=</varname></term> | |
| 1058 | <term><varname>systemd.log_level=</varname></term> | |
| 1059 | <term><varname>systemd.log_color=</varname></term> | |
| 1060 | <term><varname>systemd.log_location=</varname></term> | |
| 1061 | ||
| 1062 | <listitem><para>Controls log output, | |
| 1063 | with the same effect as the | |
| 1064 | <varname>$SYSTEMD_LOG_TARGET</varname>, <varname>$SYSTEMD_LOG_LEVEL</varname>, <varname>$SYSTEMD_LOG_COLOR</varname>, <varname>$SYSTEMD_LOG_LOCATION</varname> | |
| 1065 | environment variables described above.</para></listitem> | |
| 1066 | </varlistentry> | |
| 1067 | ||
| 0a494f1f LP |
1068 | <varlistentry> |
| 1069 | <term><varname>systemd.default_standard_output=</varname></term> | |
| 1070 | <term><varname>systemd.default_standard_error=</varname></term> | |
| 1071 | <listitem><para>Controls default | |
| 1072 | standard output/error output for | |
| 1073 | services, with the same effect as the | |
| 1074 | <option>--default-standard-output=</option> | |
| 1075 | resp. <option>--default-standard-error=</option> | |
| 1076 | command line arguments described | |
| 1077 | above.</para></listitem> | |
| 1078 | </varlistentry> | |
| 1079 | ||
| aa704ba8 LP |
1080 | <varlistentry> |
| 1081 | <term><varname>systemd.setenv=</varname></term> | |
| 1082 | ||
| 1083 | <listitem><para>Takes a string | |
| 1084 | argument in the form | |
| 1085 | VARIABLE=VALUE. May be used to set | |
| 1086 | environment variables for the init | |
| 1087 | process and all its children at boot | |
| 1088 | time. May be used more than once to | |
| 1089 | set multiple variables. If the equal | |
| 1090 | sign and variable are missing unsets | |
| 1091 | an environment variable which might be | |
| 1092 | passed in from the initial ram | |
| 1093 | disk.</para></listitem> | |
| 1094 | </varlistentry> | |
| 1095 | ||
| f3e219a2 LP |
1096 | </variablelist> |
| 1097 | </refsect1> | |
| 1098 | ||
| 2218198b LP |
1099 | <refsect1> |
| 1100 | <title>Sockets and FIFOs</title> | |
| 1101 | ||
| 1102 | <variablelist> | |
| 1103 | <varlistentry> | |
| bb29785e | 1104 | <term><filename>/run/systemd/notify</filename></term> |
| 2218198b LP |
1105 | |
| 1106 | <listitem><para>Daemon status | |
| bb29785e LP |
1107 | notification socket. This is an |
| 1108 | AF_UNIX datagram socket and is used to | |
| 1109 | implement the daemon notification | |
| 1110 | logic as implemented by | |
| 2218198b LP |
1111 | <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem> |
| 1112 | ||
| 1113 | </varlistentry> | |
| 1114 | ||
| 5dc50792 | 1115 | <varlistentry> |
| bb29785e | 1116 | <term><filename>/run/systemd/shutdownd</filename></term> |
| 5dc50792 LP |
1117 | |
| 1118 | <listitem><para>Used internally by the | |
| 1119 | <citerefentry><refentrytitle>shutdown</refentrytitle><manvolnum>8</manvolnum></citerefentry> | |
| 1120 | tool to implement delayed | |
| 1121 | shutdowns. This is an AF_UNIX datagram | |
| bb29785e | 1122 | socket.</para></listitem> |
| 5dc50792 LP |
1123 | </varlistentry> |
| 1124 | ||
| 2218198b | 1125 | <varlistentry> |
| bb29785e | 1126 | <term><filename>/run/systemd/private</filename></term> |
| 2218198b LP |
1127 | |
| 1128 | <listitem><para>Used internally as | |
| 1129 | communication channel between | |
| 1130 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
| 1131 | and the systemd process. This is an | |
| bb29785e LP |
1132 | AF_UNIX stream socket. This interface |
| 1133 | is private to systemd and should not | |
| 1134 | be used in external | |
| 2218198b LP |
1135 | projects.</para></listitem> |
| 1136 | </varlistentry> | |
| 1137 | ||
| 1138 | <varlistentry> | |
| 1139 | <term><filename>/dev/initctl</filename></term> | |
| 1140 | ||
| 1141 | <listitem><para>Limited compatibility | |
| 1142 | support for the SysV client interface, | |
| 1143 | as implemented by the | |
| 1144 | <filename>systemd-initctl.service</filename> | |
| 1145 | unit. This is a named pipe in the file | |
| 1146 | system. This interface is obsolete and | |
| 1147 | should not be used in new | |
| 1148 | applications.</para></listitem> | |
| 1149 | </varlistentry> | |
| 1150 | </variablelist> | |
| 9e632bf7 LP |
1151 | </refsect1> |
| 1152 | ||
| 9e632bf7 LP |
1153 | <refsect1> |
| 1154 | <title>See Also</title> | |
| 1155 | <para> | |
| 7874bcd6 LP |
1156 | <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
| 1157 | <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>, | |
| 7874bcd6 | 1158 | <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>, |
| 9e632bf7 | 1159 | <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| 7874bcd6 LP |
1160 | <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>, |
| 1161 | <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
| 1162 | <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>, | |
| 1163 | <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry> | |
| 9e632bf7 LP |
1164 | </para> |
| 1165 | </refsect1> | |
| 1166 | ||
| 1167 | </refentry> |