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| 18 | </style><a href="index.html">Index </a>· | |
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| 14228c0d | 22 | <a href="../libudev/index.html">gudev </a><span style="float:right">systemd 208</span><hr><div class="refentry"><a name="systemd"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd, init — systemd system and service manager</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p><code class="command">systemd [OPTIONS...]</code> </p></div><div class="cmdsynopsis"><p><code class="command">init [OPTIONS...] {COMMAND}</code> </p></div></div><div class="refsect1"><a name="idm274698355472"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description">¶</a></h2><p>systemd is a system and service manager for |
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23 | Linux operating systems. When run as first process on |
| 24 | boot (as PID 1), it acts as init system that brings | |
| 25 | up and maintains userspace services.</p><p>For compatibility with SysV, if systemd is called | |
| 26 | as <span class="command"><strong>init</strong></span> and a PID that is not | |
| 27 | 1, it will execute <span class="command"><strong>telinit</strong></span> and pass | |
| 28 | all command line arguments unmodified. That means | |
| 29 | <span class="command"><strong>init</strong></span> and <span class="command"><strong>telinit</strong></span> | |
| 30 | are mostly equivalent when invoked from normal login sessions. See | |
| 31 | <a href="telinit.html"><span class="citerefentry"><span class="refentrytitle">telinit</span>(8)</span></a> | |
| 32 | for more information.</p><p>When run as system instance, systemd interprets | |
| 33 | the configuration file | |
| 34 | <code class="filename">system.conf</code>, otherwise | |
| 35 | <code class="filename">user.conf</code>. See | |
| 36 | <a href="systemd-system.conf.html"><span class="citerefentry"><span class="refentrytitle">systemd-system.conf</span>(5)</span></a> | |
| 14228c0d | 37 | for more information.</p></div><div class="refsect1"><a name="idm274698220992"></a><h2 id="Options">Options<a class="headerlink" title="Permalink to this headline" href="#Options">¶</a></h2><p>The following options are understood:</p><div class="variablelist"><dl class="variablelist"><dt id="-h"><span class="term"><code class="option">-h</code>, </span><span class="term"><code class="option">--help</code></span><a class="headerlink" title="Permalink to this term" href="#-h">¶</a></dt><dd><p>Prints a short help |
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38 | text and exits.</p></dd><dt id="--version"><span class="term"><code class="option">--version</code></span><a class="headerlink" title="Permalink to this term" href="#--version">¶</a></dt><dd><p>Prints a systemd version |
| 39 | identifier and exits.</p></dd><dt id="--test"><span class="term"><code class="option">--test</code></span><a class="headerlink" title="Permalink to this term" href="#--test">¶</a></dt><dd><p>Determine startup | |
| 40 | sequence, dump it and exit. This is an | |
| 41 | option useful for debugging | |
| 42 | only.</p></dd><dt id="--dump-configuration-items"><span class="term"><code class="option">--dump-configuration-items</code></span><a class="headerlink" title="Permalink to this term" href="#--dump-configuration-items">¶</a></dt><dd><p>Dump understood unit | |
| 43 | configuration items. This outputs a | |
| 44 | terse but complete list of | |
| 45 | configuration items understood in unit | |
| 46 | definition files.</p></dd><dt id="--introspect="><span class="term"><code class="option">--introspect=</code></span><a class="headerlink" title="Permalink to this term" href="#--introspect=">¶</a></dt><dd><p>Extract D-Bus | |
| 47 | interface introspection data. This is | |
| 48 | mostly useful at install time | |
| 49 | to generate data suitable for the | |
| 50 | D-Bus interfaces | |
| 51 | repository. Optionally the interface | |
| 52 | name for the introspection data may be | |
| 53 | specified. If omitted, the | |
| 54 | introspection data for all interfaces | |
| 55 | is dumped.</p></dd><dt id="--unit="><span class="term"><code class="option">--unit=</code></span><a class="headerlink" title="Permalink to this term" href="#--unit=">¶</a></dt><dd><p>Set default unit to | |
| 14228c0d | 56 | activate on startup. If not specified, |
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57 | defaults to |
| 58 | <code class="filename">default.target</code>.</p></dd><dt id="--system"><span class="term"><code class="option">--system</code>, </span><span class="term"><code class="option">--user</code></span><a class="headerlink" title="Permalink to this term" href="#--system">¶</a></dt><dd><p>For <code class="option">--system</code>, | |
| 59 | tell systemd to run a | |
| 60 | system instance, even if the process ID is | |
| 61 | not 1, i.e. systemd is not run as init process. | |
| 62 | <code class="option">--user</code> does the opposite, | |
| 63 | running a user instance even if the process | |
| 64 | ID is 1. | |
| 65 | Normally it should not be necessary to | |
| 66 | pass these options, as systemd | |
| 67 | automatically detects the mode it is | |
| 68 | started in. These options are hence of | |
| 69 | little use except for debugging. Note | |
| 70 | that it is not supported booting and | |
| 71 | maintaining a full system with systemd | |
| 72 | running in <code class="option">--system</code> | |
| 73 | mode, but PID not 1. In practice, | |
| 74 | passing <code class="option">--system</code> explicitly is | |
| 75 | only useful in conjunction with | |
| 76 | <code class="option">--test</code>.</p></dd><dt id="--dump-core"><span class="term"><code class="option">--dump-core</code></span><a class="headerlink" title="Permalink to this term" href="#--dump-core">¶</a></dt><dd><p>Dump core on | |
| 77 | crash. This switch has no effect when | |
| 78 | run as user | |
| 79 | instance.</p></dd><dt id="--crash-shell"><span class="term"><code class="option">--crash-shell</code></span><a class="headerlink" title="Permalink to this term" href="#--crash-shell">¶</a></dt><dd><p>Run shell on | |
| 80 | crash. This switch has no effect when | |
| 81 | run as user | |
| 82 | instance.</p></dd><dt id="--confirm-spawn"><span class="term"><code class="option">--confirm-spawn</code></span><a class="headerlink" title="Permalink to this term" href="#--confirm-spawn">¶</a></dt><dd><p>Ask for confirmation | |
| 83 | when spawning processes. This switch | |
| 84 | has no effect when run as user | |
| 85 | instance.</p></dd><dt id="--show-status="><span class="term"><code class="option">--show-status=</code></span><a class="headerlink" title="Permalink to this term" href="#--show-status=">¶</a></dt><dd><p>Show terse service | |
| 86 | status information while booting. This | |
| 87 | switch has no effect when run as user | |
| 88 | instance. Takes a boolean argument | |
| 89 | which may be omitted which is | |
| 90 | interpreted as | |
| 91 | <code class="option">true</code>.</p></dd><dt id="--log-target="><span class="term"><code class="option">--log-target=</code></span><a class="headerlink" title="Permalink to this term" href="#--log-target=">¶</a></dt><dd><p>Set log | |
| 92 | target. Argument must be one of | |
| 93 | <code class="option">console</code>, | |
| 94 | <code class="option">journal</code>, | |
| 95 | <code class="option">syslog</code>, | |
| 96 | <code class="option">kmsg</code>, | |
| 97 | <code class="option">journal-or-kmsg</code>, | |
| 98 | <code class="option">syslog-or-kmsg</code>, | |
| 99 | <code class="option">null</code>.</p></dd><dt id="--log-level="><span class="term"><code class="option">--log-level=</code></span><a class="headerlink" title="Permalink to this term" href="#--log-level=">¶</a></dt><dd><p>Set log level. As | |
| 100 | argument this accepts a numerical log | |
| 101 | level or the well-known <a href="syslog.html"><span class="citerefentry"><span class="refentrytitle">syslog</span>(3)</span></a> | |
| 102 | symbolic names (lowercase): | |
| 103 | <code class="option">emerg</code>, | |
| 104 | <code class="option">alert</code>, | |
| 105 | <code class="option">crit</code>, | |
| 106 | <code class="option">err</code>, | |
| 107 | <code class="option">warning</code>, | |
| 108 | <code class="option">notice</code>, | |
| 109 | <code class="option">info</code>, | |
| 110 | <code class="option">debug</code>.</p></dd><dt id="--log-color="><span class="term"><code class="option">--log-color=</code></span><a class="headerlink" title="Permalink to this term" href="#--log-color=">¶</a></dt><dd><p>Highlight important | |
| 111 | log messages. Argument is a boolean | |
| 14228c0d | 112 | value. If the argument is omitted, it |
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113 | defaults to |
| 114 | <code class="option">true</code>.</p></dd><dt id="--log-location="><span class="term"><code class="option">--log-location=</code></span><a class="headerlink" title="Permalink to this term" href="#--log-location=">¶</a></dt><dd><p>Include code location | |
| 115 | in log messages. This is mostly | |
| 116 | relevant for debugging | |
| 117 | purposes. Argument is a boolean | |
| 118 | value. If the argument is omitted | |
| 119 | it defaults to | |
| 120 | <code class="option">true</code>.</p></dd><dt id="--default-standard-output="><span class="term"><code class="option">--default-standard-output=</code>, </span><span class="term"><code class="option">--default-standard-error=</code></span><a class="headerlink" title="Permalink to this term" href="#--default-standard-output=">¶</a></dt><dd><p>Sets the default | |
| 121 | output or error output for all | |
| 122 | services and sockets, respectively. That is, controls | |
| 123 | the default for | |
| 124 | <code class="option">StandardOutput=</code> | |
| 125 | and <code class="option">StandardError=</code> | |
| 126 | (see | |
| 127 | <a href="systemd.exec.html"><span class="citerefentry"><span class="refentrytitle">systemd.exec</span>(5)</span></a> | |
| 128 | for details). Takes one of | |
| 129 | <code class="option">inherit</code>, | |
| 130 | <code class="option">null</code>, | |
| 131 | <code class="option">tty</code>, | |
| 132 | <code class="option">journal</code>, | |
| 133 | <code class="option">journal+console</code>, | |
| 134 | <code class="option">syslog</code>, | |
| 135 | <code class="option">syslog+console</code>, | |
| 136 | <code class="option">kmsg</code>, | |
| 137 | <code class="option">kmsg+console</code>. If the | |
| 138 | argument is omitted | |
| 139 | <code class="option">--default-standard-output=</code> | |
| 140 | defaults to <code class="option">journal</code> | |
| 141 | and | |
| 142 | <code class="option">--default-standard-error=</code> | |
| 143 | to | |
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144 | <code class="option">inherit</code>.</p></dd></dl></div></div><div class="refsect1"><a name="idm274693401328"></a><h2 id="Concepts">Concepts<a class="headerlink" title="Permalink to this headline" href="#Concepts">¶</a></h2><p>systemd provides a dependency system between |
| 145 | various entities called "units" of 12 different | |
| 146 | types. Units encapsulate various objects that are | |
| 147 | relevant for system boot-up and maintenance. The | |
| 148 | majority of units are configured in unit configuration | |
| 149 | files, whose syntax and basic set of options is | |
| 150 | described in | |
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151 | <a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>, |
| 152 | however some are created automatically from other | |
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153 | configuration, dynamically from system state or |
| 154 | programmatically at runtime. Units may be "active" | |
| 155 | (meaning started, bound, plugged in, ..., depending on | |
| 156 | the unit type, see below), or "inactive" (meaning | |
| 157 | stopped, unbound, unplugged, ...), as well as in the | |
| 158 | process of being activated or deactivated, | |
| 159 | i.e. between the two states (these states are called | |
| 160 | "activating", "deactivating"). A special "failed" | |
| 161 | state is available as well, which is very similar to | |
| 162 | "inactive" and is entered when the service failed in | |
| 163 | some way (process returned error code on exit, or | |
| 164 | crashed, or an operation timed out). If this state is | |
| 165 | entered, the cause will be logged, for later | |
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166 | reference. Note that the various unit types may have a |
| 167 | number of additional substates, which are mapped to | |
| 168 | the five generalized unit states described | |
| 14228c0d | 169 | here.</p><p>The following unit types are available:</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>Service units, which start and control |
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170 | daemons and the processes they consist of. For |
| 171 | details see | |
| 172 | <a href="systemd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd.service</span>(5)</span></a>.</p></li><li class="listitem"><p>Socket units, which | |
| 173 | encapsulate local IPC or network sockets in | |
| 174 | the system, useful for socket-based | |
| 175 | activation. For details about socket units see | |
| 176 | <a href="systemd.socket.html"><span class="citerefentry"><span class="refentrytitle">systemd.socket</span>(5)</span></a>, | |
| 177 | for details on socket-based activation and | |
| 178 | other forms of activation, see | |
| 179 | <a href="daemon.html"><span class="citerefentry"><span class="refentrytitle">daemon</span>(7)</span></a>.</p></li><li class="listitem"><p>Target units are useful to | |
| 180 | group units, or provide well-known | |
| 181 | synchronization points during boot-up, see | |
| 182 | <a href="systemd.target.html"><span class="citerefentry"><span class="refentrytitle">systemd.target</span>(5)</span></a>.</p></li><li class="listitem"><p>Device units expose kernel | |
| 183 | devices in systemd and may be used to | |
| 184 | implement device-based activation. For details | |
| 185 | see | |
| 186 | <a href="systemd.device.html"><span class="citerefentry"><span class="refentrytitle">systemd.device</span>(5)</span></a>.</p></li><li class="listitem"><p>Mount units control mount | |
| 187 | points in the file system, for details see | |
| 188 | <a href="systemd.mount.html"><span class="citerefentry"><span class="refentrytitle">systemd.mount</span>(5)</span></a>.</p></li><li class="listitem"><p>Automount units provide | |
| 189 | automount capabilities, for on-demand mounting | |
| 190 | of file systems as well as parallelized | |
| 191 | boot-up. See | |
| 192 | <a href="systemd.automount.html"><span class="citerefentry"><span class="refentrytitle">systemd.automount</span>(5)</span></a>.</p></li><li class="listitem"><p>Snapshot units can be used to | |
| 193 | temporarily save the state of the set of | |
| 194 | systemd units, which later may be restored by | |
| 195 | activating the saved snapshot unit. For more | |
| 196 | information see | |
| 197 | <a href="systemd.snapshot.html"><span class="citerefentry"><span class="refentrytitle">systemd.snapshot</span>(5)</span></a>.</p></li><li class="listitem"><p>Timer units are useful for | |
| 198 | triggering activation of other units based on | |
| 199 | timers. You may find details in | |
| 200 | <a href="systemd.timer.html"><span class="citerefentry"><span class="refentrytitle">systemd.timer</span>(5)</span></a>.</p></li><li class="listitem"><p>Swap units are very similar to | |
| 201 | mount units and encapsulate memory swap | |
| 202 | partitions or files of the operating | |
| 203 | system. They are described in <a href="systemd.swap.html"><span class="citerefentry"><span class="refentrytitle">systemd.swap</span>(5)</span></a>.</p></li><li class="listitem"><p>Path units may be used | |
| 204 | to activate other services when file system | |
| 205 | objects change or are modified. See | |
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206 | <a href="systemd.path.html"><span class="citerefentry"><span class="refentrytitle">systemd.path</span>(5)</span></a>.</p></li><li class="listitem"><p>Slice units may be used to |
| 207 | group units which manage system processes | |
| 208 | (such as service and scope units) in a | |
| 209 | hierarchical tree for resource management | |
| 210 | purposes. See | |
| 211 | <a href="systemd.slice.html"><span class="citerefentry"><span class="refentrytitle">systemd.slice</span>(5)</span></a>.</p></li><li class="listitem"><p>Scope units are similar to | |
| 212 | service units, but manage foreign processes | |
| 213 | instead of starting them as well. See | |
| 214 | <a href="systemd.scope.html"><span class="citerefentry"><span class="refentrytitle">systemd.scope</span>(5)</span></a>.</p></li></ol></div><p>Units are named as their configuration | |
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215 | files. Some units have special semantics. A detailed |
| 216 | list is available in | |
| 217 | <a href="systemd.special.html"><span class="citerefentry"><span class="refentrytitle">systemd.special</span>(7)</span></a>.</p><p>systemd knows various kinds of dependencies, | |
| 218 | including positive and negative requirement | |
| 219 | dependencies (i.e. <code class="varname">Requires=</code> and | |
| 220 | <code class="varname">Conflicts=</code>) as well as ordering | |
| 221 | dependencies (<code class="varname">After=</code> and | |
| 222 | <code class="varname">Before=</code>). NB: ordering and | |
| 223 | requirement dependencies are orthogonal. If only a | |
| 224 | requirement dependency exists between two units | |
| 225 | (e.g. <code class="filename">foo.service</code> requires | |
| 226 | <code class="filename">bar.service</code>), but no ordering | |
| 227 | dependency (e.g. <code class="filename">foo.service</code> | |
| 228 | after <code class="filename">bar.service</code>) and both are | |
| 229 | requested to start, they will be started in | |
| 230 | parallel. It is a common pattern that both requirement | |
| 231 | and ordering dependencies are placed between two | |
| 232 | units. Also note that the majority of dependencies are | |
| 233 | implicitly created and maintained by systemd. In most | |
| 234 | cases it should be unnecessary to declare additional | |
| 235 | dependencies manually, however it is possible to do | |
| 236 | this.</p><p>Application programs and units (via | |
| 237 | dependencies) may request state changes of units. In | |
| 238 | systemd, these requests are encapsulated as 'jobs' and | |
| 239 | maintained in a job queue. Jobs may succeed or can | |
| 240 | fail, their execution is ordered based on the ordering | |
| 241 | dependencies of the units they have been scheduled | |
| 242 | for.</p><p>On boot systemd activates the target unit | |
| 243 | <code class="filename">default.target</code> whose job is to | |
| 244 | activate on-boot services and other on-boot units by | |
| 245 | pulling them in via dependencies. Usually the unit | |
| 246 | name is just an alias (symlink) for either | |
| 247 | <code class="filename">graphical.target</code> (for | |
| 248 | fully-featured boots into the UI) or | |
| 249 | <code class="filename">multi-user.target</code> (for limited | |
| 250 | console-only boots for use in embedded or server | |
| 251 | environments, or similar; a subset of | |
| 14228c0d | 252 | graphical.target). However, it is at the discretion of |
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253 | the administrator to configure it as an alias to any |
| 254 | other target unit. See | |
| 255 | <a href="systemd.special.html"><span class="citerefentry"><span class="refentrytitle">systemd.special</span>(7)</span></a> | |
| 256 | for details about these target units.</p><p>Processes systemd spawns are placed in | |
| 257 | individual Linux control groups named after the unit | |
| 258 | which they belong to in the private systemd | |
| 14228c0d | 259 | hierarchy. (see <a class="ulink" href="https://www.kernel.org/doc/Documentation/cgroups/cgroups.txt" target="_top">cgroups.txt</a> |
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260 | for more information about control groups, or short |
| 261 | "cgroups"). systemd uses this to effectively keep | |
| 262 | track of processes. Control group information is | |
| 263 | maintained in the kernel, and is accessible via the | |
| 264 | file system hierarchy (beneath | |
| 265 | <code class="filename">/sys/fs/cgroup/systemd/</code>), or in tools | |
| 266 | such as | |
| 267 | <a href="ps.html"><span class="citerefentry"><span class="refentrytitle">ps</span>(1)</span></a> | |
| 268 | (<span class="command"><strong>ps xawf -eo pid,user,cgroup,args</strong></span> | |
| 269 | is particularly useful to list all processes and the | |
| 270 | systemd units they belong to.).</p><p>systemd is compatible with the SysV init system | |
| 271 | to a large degree: SysV init scripts are supported and | |
| 272 | simply read as an alternative (though limited) | |
| 273 | configuration file format. The SysV | |
| 274 | <code class="filename">/dev/initctl</code> interface is | |
| 275 | provided, and compatibility implementations of the | |
| 276 | various SysV client tools are available. In addition to | |
| 277 | that, various established Unix functionality such as | |
| 278 | <code class="filename">/etc/fstab</code> or the | |
| 279 | <code class="filename">utmp</code> database are | |
| 280 | supported.</p><p>systemd has a minimal transaction system: if a | |
| 281 | unit is requested to start up or shut down it will add | |
| 282 | it and all its dependencies to a temporary | |
| 283 | transaction. Then, it will verify if the transaction | |
| 284 | is consistent (i.e. whether the ordering of all units | |
| 285 | is cycle-free). If it is not, systemd will try to fix | |
| 286 | it up, and removes non-essential jobs from the | |
| 287 | transaction that might remove the loop. Also, systemd | |
| 288 | tries to suppress non-essential jobs in the | |
| 289 | transaction that would stop a running service. Finally | |
| 290 | it is checked whether the jobs of the transaction | |
| 291 | contradict jobs that have already been queued, and | |
| 292 | optionally the transaction is aborted then. If all | |
| 293 | worked out and the transaction is consistent and | |
| 294 | minimized in its impact it is merged with all already | |
| 295 | outstanding jobs and added to the run | |
| 296 | queue. Effectively this means that before executing a | |
| 297 | requested operation, systemd will verify that it makes | |
| 298 | sense, fixing it if possible, and only failing if it | |
| 299 | really cannot work.</p><p>Systemd contains native implementations of | |
| 300 | various tasks that need to be executed as part of the | |
| 14228c0d | 301 | boot process. For example, it sets the hostname or |
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302 | configures the loopback network device. It also sets |
| 303 | up and mounts various API file systems, such as | |
| 304 | <code class="filename">/sys</code> or | |
| 305 | <code class="filename">/proc</code>.</p><p>For more information about the concepts and | |
| 306 | ideas behind systemd please refer to the <a class="ulink" href="http://0pointer.de/blog/projects/systemd.html" target="_top">Original | |
| 307 | Design Document</a>.</p><p>Note that some but not all interfaces provided | |
| 308 | by systemd are covered by the <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise" target="_top">Interface | |
| 309 | Stability Promise</a>.</p><p>Units may be generated dynamically at boot and | |
| 310 | system manager reload time, for example based on other | |
| 311 | configuration files or parameters passed on the kernel | |
| 312 | command line. For details see the <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/Generators" target="_top">Generators | |
| 313 | Specification</a>.</p><p>Systems which invoke systemd in a container | |
| 314 | or initrd environment should implement the | |
| 315 | <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface" target="_top">Container | |
| 316 | Interface</a> or <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/InitrdInterface" target="_top">initrd | |
| 14228c0d | 317 | Interface</a> specifications, respectively.</p></div><div class="refsect1"><a name="idm274693349824"></a><h2 id="Directories">Directories<a class="headerlink" title="Permalink to this headline" href="#Directories">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="System unit directories"><span class="term">System unit directories</span><a class="headerlink" title="Permalink to this term" href="#System%20unit%20directories">¶</a></dt><dd><p>The systemd system |
| 663996b3 MS |
318 | manager reads unit configuration from |
| 319 | various directories. Packages that | |
| 320 | want to install unit files shall place | |
| 321 | them in the directory returned by | |
| 322 | <span class="command"><strong>pkg-config systemd | |
| 323 | --variable=systemdsystemunitdir</strong></span>. Other | |
| 324 | directories checked are | |
| 325 | <code class="filename">/usr/local/lib/systemd/system</code> | |
| 326 | and | |
| 327 | <code class="filename">/usr/lib/systemd/system</code>. User | |
| 328 | configuration always takes | |
| 329 | precedence. <span class="command"><strong>pkg-config | |
| 330 | systemd | |
| 331 | --variable=systemdsystemconfdir</strong></span> | |
| 332 | returns the path of the system | |
| 333 | configuration directory. Packages | |
| 334 | should alter the content of these | |
| 335 | directories only with the | |
| 336 | <span class="command"><strong>enable</strong></span> and | |
| 337 | <span class="command"><strong>disable</strong></span> commands of | |
| 338 | the | |
| 339 | <a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a> | |
| 340 | tool. Full list of directories is provided in | |
| 341 | <a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>. | |
| 342 | </p></dd></dl></div><div class="variablelist"><dl class="variablelist"><dt id="User unit directories"><span class="term">User unit directories</span><a class="headerlink" title="Permalink to this term" href="#User%20unit%20directories">¶</a></dt><dd><p>Similar rules apply | |
| 343 | for the user unit | |
| 344 | directories. However, here the <a class="ulink" href="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html" target="_top">XDG | |
| 345 | Base Directory specification</a> | |
| 346 | is followed to find | |
| 347 | units. Applications should place their | |
| 348 | unit files in the directory returned | |
| 349 | by <span class="command"><strong>pkg-config systemd | |
| 350 | --variable=systemduserunitdir</strong></span>. Global | |
| 351 | configuration is done in the directory | |
| 352 | reported by <span class="command"><strong>pkg-config | |
| 353 | systemd | |
| 354 | --variable=systemduserconfdir</strong></span>. The | |
| 355 | <span class="command"><strong>enable</strong></span> and | |
| 356 | <span class="command"><strong>disable</strong></span> commands of | |
| 357 | the | |
| 358 | <a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a> | |
| 359 | tool can handle both global (i.e. for | |
| 360 | all users) and private (for one user) | |
| 361 | enabling/disabling of | |
| 362 | units. Full list of directories is provided in | |
| 363 | <a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>. | |
| 364 | </p></dd></dl></div><div class="variablelist"><dl class="variablelist"><dt id="SysV init scripts directory"><span class="term">SysV init scripts directory</span><a class="headerlink" title="Permalink to this term" href="#SysV%20init%20scripts%20directory">¶</a></dt><dd><p>The location of the | |
| 365 | SysV init script directory varies | |
| 366 | between distributions. If systemd | |
| 367 | cannot find a native unit file for a | |
| 368 | requested service, it will look for a | |
| 369 | SysV init script of the same name | |
| 370 | (with the | |
| 371 | <code class="filename">.service</code> suffix | |
| 372 | removed).</p></dd></dl></div><div class="variablelist"><dl class="variablelist"><dt id="SysV runlevel link farm directory"><span class="term">SysV runlevel link farm directory</span><a class="headerlink" title="Permalink to this term" href="#SysV%20runlevel%20link%20farm%20directory">¶</a></dt><dd><p>The location of the | |
| 373 | SysV runlevel link farm directory | |
| 374 | varies between distributions. systemd | |
| 375 | will take the link farm into account | |
| 376 | when figuring out whether a service | |
| 377 | shall be enabled. Note that a service | |
| 378 | unit with a native unit configuration | |
| 379 | file cannot be started by activating it | |
| 380 | in the SysV runlevel link | |
| 14228c0d | 381 | farm.</p></dd></dl></div></div><div class="refsect1"><a name="idm274693328032"></a><h2 id="Signals">Signals<a class="headerlink" title="Permalink to this headline" href="#Signals">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="SIGTERM"><span class="term"><code class="constant">SIGTERM</code></span><a class="headerlink" title="Permalink to this term" href="#SIGTERM">¶</a></dt><dd><p>Upon receiving this |
| 663996b3 MS |
382 | signal the systemd system manager |
| 383 | serializes its state, reexecutes | |
| 384 | itself and deserializes the saved | |
| 385 | state again. This is mostly equivalent | |
| 386 | to <span class="command"><strong>systemctl | |
| 387 | daemon-reexec</strong></span>.</p><p>systemd user managers will | |
| 388 | start the | |
| 389 | <code class="filename">exit.target</code> unit | |
| 390 | when this signal is received. This is | |
| 391 | mostly equivalent to | |
| 392 | <span class="command"><strong>systemctl --user start | |
| 14228c0d | 393 | exit.target</strong></span>.</p></dd><dt id="SIGINT"><span class="term"><code class="constant">SIGINT</code></span><a class="headerlink" title="Permalink to this term" href="#SIGINT">¶</a></dt><dd><p>Upon receiving this |
| 663996b3 MS |
394 | signal the systemd system manager will |
| 395 | start the | |
| 396 | <code class="filename">ctrl-alt-del.target</code> unit. This | |
| 397 | is mostly equivalent to | |
| 398 | <span class="command"><strong>systemctl start | |
| 399 | ctl-alt-del.target</strong></span>.</p><p>systemd user managers | |
| 400 | treat this signal the same way as | |
| 14228c0d | 401 | <code class="constant">SIGTERM</code>.</p></dd><dt id="SIGWINCH"><span class="term"><code class="constant">SIGWINCH</code></span><a class="headerlink" title="Permalink to this term" href="#SIGWINCH">¶</a></dt><dd><p>When this signal is |
| 663996b3 MS |
402 | received the systemd system manager |
| 403 | will start the | |
| 404 | <code class="filename">kbrequest.target</code> | |
| 405 | unit. This is mostly equivalent to | |
| 406 | <span class="command"><strong>systemctl start | |
| 407 | kbrequest.target</strong></span>.</p><p>This signal is ignored by | |
| 408 | systemd user | |
| 14228c0d | 409 | managers.</p></dd><dt id="SIGPWR"><span class="term"><code class="constant">SIGPWR</code></span><a class="headerlink" title="Permalink to this term" href="#SIGPWR">¶</a></dt><dd><p>When this signal is |
| 663996b3 MS |
410 | received the systemd manager |
| 411 | will start the | |
| 412 | <code class="filename">sigpwr.target</code> | |
| 413 | unit. This is mostly equivalent to | |
| 414 | <span class="command"><strong>systemctl start | |
| 14228c0d | 415 | sigpwr.target</strong></span>.</p></dd><dt id="SIGUSR1"><span class="term"><code class="constant">SIGUSR1</code></span><a class="headerlink" title="Permalink to this term" href="#SIGUSR1">¶</a></dt><dd><p>When this signal is |
| 663996b3 MS |
416 | received the systemd manager will try |
| 417 | to reconnect to the D-Bus | |
| 14228c0d | 418 | bus.</p></dd><dt id="SIGUSR2"><span class="term"><code class="constant">SIGUSR2</code></span><a class="headerlink" title="Permalink to this term" href="#SIGUSR2">¶</a></dt><dd><p>When this signal is |
| 663996b3 MS |
419 | received the systemd manager will log |
| 420 | its complete state in human readable | |
| 421 | form. The data logged is the same as | |
| 422 | printed by <span class="command"><strong>systemctl | |
| 14228c0d | 423 | dump</strong></span>.</p></dd><dt id="SIGHUP"><span class="term"><code class="constant">SIGHUP</code></span><a class="headerlink" title="Permalink to this term" href="#SIGHUP">¶</a></dt><dd><p>Reloads the complete |
| 663996b3 MS |
424 | daemon configuration. This is mostly |
| 425 | equivalent to <span class="command"><strong>systemctl | |
| 14228c0d | 426 | daemon-reload</strong></span>.</p></dd><dt id="SIGRTMIN+0"><span class="term"><code class="constant">SIGRTMIN+0</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+0">¶</a></dt><dd><p>Enters default mode, starts the |
| 663996b3 MS |
427 | <code class="filename">default.target</code> |
| 428 | unit. This is mostly equivalent to | |
| 429 | <span class="command"><strong>systemctl start | |
| 14228c0d | 430 | default.target</strong></span>.</p></dd><dt id="SIGRTMIN+1"><span class="term"><code class="constant">SIGRTMIN+1</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+1">¶</a></dt><dd><p>Enters rescue mode, |
| 663996b3 MS |
431 | starts the |
| 432 | <code class="filename">rescue.target</code> | |
| 433 | unit. This is mostly equivalent to | |
| 434 | <span class="command"><strong>systemctl isolate | |
| 14228c0d | 435 | rescue.target</strong></span>.</p></dd><dt id="SIGRTMIN+2"><span class="term"><code class="constant">SIGRTMIN+2</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+2">¶</a></dt><dd><p>Enters emergency mode, |
| 663996b3 MS |
436 | starts the |
| 437 | <code class="filename">emergency.service</code> | |
| 438 | unit. This is mostly equivalent to | |
| 439 | <span class="command"><strong>systemctl isolate | |
| 14228c0d | 440 | emergency.service</strong></span>.</p></dd><dt id="SIGRTMIN+3"><span class="term"><code class="constant">SIGRTMIN+3</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+3">¶</a></dt><dd><p>Halts the machine, |
| 663996b3 MS |
441 | starts the |
| 442 | <code class="filename">halt.target</code> | |
| 443 | unit. This is mostly equivalent to | |
| 444 | <span class="command"><strong>systemctl start | |
| 14228c0d | 445 | halt.target</strong></span>.</p></dd><dt id="SIGRTMIN+4"><span class="term"><code class="constant">SIGRTMIN+4</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+4">¶</a></dt><dd><p>Powers off the machine, |
| 663996b3 MS |
446 | starts the |
| 447 | <code class="filename">poweroff.target</code> | |
| 448 | unit. This is mostly equivalent to | |
| 449 | <span class="command"><strong>systemctl start | |
| 14228c0d | 450 | poweroff.target</strong></span>.</p></dd><dt id="SIGRTMIN+5"><span class="term"><code class="constant">SIGRTMIN+5</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+5">¶</a></dt><dd><p>Reboots the machine, |
| 663996b3 MS |
451 | starts the |
| 452 | <code class="filename">reboot.target</code> | |
| 453 | unit. This is mostly equivalent to | |
| 454 | <span class="command"><strong>systemctl start | |
| 14228c0d | 455 | reboot.target</strong></span>.</p></dd><dt id="SIGRTMIN+6"><span class="term"><code class="constant">SIGRTMIN+6</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+6">¶</a></dt><dd><p>Reboots the machine via kexec, |
| 663996b3 MS |
456 | starts the |
| 457 | <code class="filename">kexec.target</code> | |
| 458 | unit. This is mostly equivalent to | |
| 459 | <span class="command"><strong>systemctl start | |
| 14228c0d | 460 | kexec.target</strong></span>.</p></dd><dt id="SIGRTMIN+13"><span class="term"><code class="constant">SIGRTMIN+13</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+13">¶</a></dt><dd><p>Immediately halts the machine.</p></dd><dt id="SIGRTMIN+14"><span class="term"><code class="constant">SIGRTMIN+14</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+14">¶</a></dt><dd><p>Immediately powers off the machine.</p></dd><dt id="SIGRTMIN+15"><span class="term"><code class="constant">SIGRTMIN+15</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+15">¶</a></dt><dd><p>Immediately reboots the machine.</p></dd><dt id="SIGRTMIN+16"><span class="term"><code class="constant">SIGRTMIN+16</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+16">¶</a></dt><dd><p>Immediately reboots the machine with kexec.</p></dd><dt id="SIGRTMIN+20"><span class="term"><code class="constant">SIGRTMIN+20</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+20">¶</a></dt><dd><p>Enables display of |
| 663996b3 MS |
461 | status messages on the console, as |
| 462 | controlled via | |
| 463 | <code class="varname">systemd.show_status=1</code> | |
| 464 | on the kernel command | |
| 14228c0d | 465 | line.</p></dd><dt id="SIGRTMIN+21"><span class="term"><code class="constant">SIGRTMIN+21</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+21">¶</a></dt><dd><p>Disables display of |
| 663996b3 MS |
466 | status messages on the console, as |
| 467 | controlled via | |
| 468 | <code class="varname">systemd.show_status=0</code> | |
| 469 | on the kernel command | |
| 14228c0d MB |
470 | line.</p></dd><dt id="SIGRTMIN+22"><span class="term"><code class="constant">SIGRTMIN+22</code>, </span><span class="term"><code class="constant">SIGRTMIN+23</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+22">¶</a></dt><dd><p>Sets the log level to |
| 471 | "<code class="literal">debug</code>" | |
| 472 | (or "<code class="literal">info</code>" on | |
| 473 | <code class="constant">SIGRTMIN+23</code>), as | |
| 663996b3 MS |
474 | controlled via |
| 475 | <code class="varname">systemd.log_level=debug</code> | |
| 476 | (or <code class="varname">systemd.log_level=info</code> | |
| 14228c0d | 477 | on <code class="constant">SIGRTMIN+23</code>) on |
| 663996b3 | 478 | the kernel command |
| 14228c0d | 479 | line.</p></dd><dt id="SIGRTMIN+24"><span class="term"><code class="constant">SIGRTMIN+24</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+24">¶</a></dt><dd><p>Immediately exits the |
| 663996b3 | 480 | manager (only available for --user |
| 14228c0d MB |
481 | instances).</p></dd><dt id="SIGRTMIN+26"><span class="term"><code class="constant">SIGRTMIN+26</code>, </span><span class="term"><code class="constant">SIGRTMIN+27</code>, </span><span class="term"><code class="constant">SIGRTMIN+28</code>, </span><span class="term"><code class="constant">SIGRTMIN+29</code></span><a class="headerlink" title="Permalink to this term" href="#SIGRTMIN+26">¶</a></dt><dd><p>Sets the log level to |
| 482 | "<code class="literal">journal-or-kmsg</code>" | |
| 483 | (or "<code class="literal">console</code>" on | |
| 484 | <code class="constant">SIGRTMIN+27</code>, | |
| 485 | "<code class="literal">kmsg</code>" on | |
| 486 | <code class="constant">SIGRTMIN+28</code>, | |
| 487 | or "<code class="literal">syslog-or-kmsg</code>" | |
| 488 | on <code class="constant">SIGRTMIN+29</code>), as | |
| 663996b3 MS |
489 | controlled via |
| 490 | <code class="varname">systemd.log_target=journal-or-kmsg</code> | |
| 491 | (or <code class="varname">systemd.log_target=console</code> | |
| 14228c0d | 492 | on <code class="constant">SIGRTMIN+27</code>, |
| 663996b3 | 493 | <code class="varname">systemd.log_target=kmsg</code> |
| 14228c0d | 494 | on <code class="constant">SIGRTMIN+28</code>, |
| 663996b3 MS |
495 | or |
| 496 | <code class="varname">systemd.log_target=syslog-or-kmsg</code> | |
| 14228c0d | 497 | on <code class="constant">SIGRTMIN+29</code>) on |
| 663996b3 | 498 | the kernel command |
| 14228c0d | 499 | line.</p></dd></dl></div></div><div class="refsect1"><a name="idm274693259360"></a><h2 id="Environment">Environment<a class="headerlink" title="Permalink to this headline" href="#Environment">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="$SYSTEMD_LOG_LEVEL"><span class="term"><code class="varname">$SYSTEMD_LOG_LEVEL</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_LOG_LEVEL">¶</a></dt><dd><p>systemd reads the |
| 663996b3 MS |
500 | log level from this environment |
| 501 | variable. This can be overridden with | |
| 502 | <code class="option">--log-level=</code>.</p></dd><dt id="$SYSTEMD_LOG_TARGET"><span class="term"><code class="varname">$SYSTEMD_LOG_TARGET</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_LOG_TARGET">¶</a></dt><dd><p>systemd reads the | |
| 503 | log target from this environment | |
| 504 | variable. This can be overridden with | |
| 505 | <code class="option">--log-target=</code>.</p></dd><dt id="$SYSTEMD_LOG_COLOR"><span class="term"><code class="varname">$SYSTEMD_LOG_COLOR</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_LOG_COLOR">¶</a></dt><dd><p>Controls whether | |
| 506 | systemd highlights important log | |
| 507 | messages. This can be overridden with | |
| 508 | <code class="option">--log-color=</code>.</p></dd><dt id="$SYSTEMD_LOG_LOCATION"><span class="term"><code class="varname">$SYSTEMD_LOG_LOCATION</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_LOG_LOCATION">¶</a></dt><dd><p>Controls whether | |
| 509 | systemd prints the code location along | |
| 510 | with log messages. This can be | |
| 511 | overridden with | |
| 512 | <code class="option">--log-location=</code>.</p></dd><dt id="$XDG_CONFIG_HOME"><span class="term"><code class="varname">$XDG_CONFIG_HOME</code>, </span><span class="term"><code class="varname">$XDG_CONFIG_DIRS</code>, </span><span class="term"><code class="varname">$XDG_DATA_HOME</code>, </span><span class="term"><code class="varname">$XDG_DATA_DIRS</code></span><a class="headerlink" title="Permalink to this term" href="#%24XDG_CONFIG_HOME">¶</a></dt><dd><p>The systemd user | |
| 513 | manager uses these variables in | |
| 514 | accordance to the <a class="ulink" href="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html" target="_top">XDG | |
| 515 | Base Directory specification</a> | |
| 516 | to find its configuration.</p></dd><dt id="$SYSTEMD_UNIT_PATH"><span class="term"><code class="varname">$SYSTEMD_UNIT_PATH</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_UNIT_PATH">¶</a></dt><dd><p>Controls where systemd | |
| 517 | looks for unit | |
| 518 | files.</p></dd><dt id="$SYSTEMD_SYSVINIT_PATH"><span class="term"><code class="varname">$SYSTEMD_SYSVINIT_PATH</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_SYSVINIT_PATH">¶</a></dt><dd><p>Controls where systemd | |
| 519 | looks for SysV init scripts.</p></dd><dt id="$SYSTEMD_SYSVRCND_PATH"><span class="term"><code class="varname">$SYSTEMD_SYSVRCND_PATH</code></span><a class="headerlink" title="Permalink to this term" href="#%24SYSTEMD_SYSVRCND_PATH">¶</a></dt><dd><p>Controls where systemd | |
| 520 | looks for SysV init script runlevel link | |
| 521 | farms.</p></dd><dt id="$LISTEN_PID"><span class="term"><code class="varname">$LISTEN_PID</code>, </span><span class="term"><code class="varname">$LISTEN_FDS</code></span><a class="headerlink" title="Permalink to this term" href="#%24LISTEN_PID">¶</a></dt><dd><p>Set by systemd for | |
| 522 | supervised processes during | |
| 523 | socket-based activation. See | |
| 524 | <a href="sd_listen_fds.html"><span class="citerefentry"><span class="refentrytitle">sd_listen_fds</span>(3)</span></a> | |
| 525 | for more information. | |
| 526 | </p></dd><dt id="$NOTIFY_SOCKET"><span class="term"><code class="varname">$NOTIFY_SOCKET</code></span><a class="headerlink" title="Permalink to this term" href="#%24NOTIFY_SOCKET">¶</a></dt><dd><p>Set by systemd for | |
| 527 | supervised processes for status and | |
| 528 | start-up completion notification. See | |
| 529 | <a href="sd_notify.html"><span class="citerefentry"><span class="refentrytitle">sd_notify</span>(3)</span></a> | |
| 530 | for more information. | |
| 14228c0d | 531 | </p></dd></dl></div></div><div class="refsect1"><a name="idm274693235936"></a><h2 id="Kernel Command Line">Kernel Command Line<a class="headerlink" title="Permalink to this headline" href="#Kernel%20Command%20Line">¶</a></h2><p>When run as system instance systemd parses a |
| 663996b3 | 532 | number of kernel command line |
| 14228c0d | 533 | arguments<a href="#ftn.idm274693234912" class="footnote" name="idm274693234912"><sup class="footnote">[1]</sup></a>:</p><div class="variablelist"><dl class="variablelist"><dt id="systemd.unit="><span class="term"><code class="varname">systemd.unit=</code>, </span><span class="term"><code class="varname">rd.systemd.unit=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.unit=">¶</a></dt><dd><p>Overrides the unit to |
| 663996b3 MS |
534 | activate on boot. Defaults to |
| 535 | <code class="filename">default.target</code>. This | |
| 536 | may be used to temporarily boot into a | |
| 537 | different boot unit, for example | |
| 538 | <code class="filename">rescue.target</code> or | |
| 539 | <code class="filename">emergency.service</code>. See | |
| 540 | <a href="systemd.special.html"><span class="citerefentry"><span class="refentrytitle">systemd.special</span>(7)</span></a> | |
| 541 | for details about these units. The | |
| 542 | option prefixed with | |
| 14228c0d | 543 | "<code class="literal">rd.</code>" is honored |
| 663996b3 | 544 | only in the initial RAM disk (initrd), |
| 14228c0d | 545 | while the one that is not prefixed only |
| 663996b3 | 546 | in the main system.</p></dd><dt id="systemd.dump_core="><span class="term"><code class="varname">systemd.dump_core=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.dump_core=">¶</a></dt><dd><p>Takes a boolean |
| 14228c0d | 547 | argument. If <code class="option">true</code>, |
| 663996b3 | 548 | systemd dumps core when it |
| 14228c0d | 549 | crashes. Otherwise, no core dump is |
| 663996b3 MS |
550 | created. Defaults to |
| 551 | <code class="option">true</code>.</p></dd><dt id="systemd.crash_shell="><span class="term"><code class="varname">systemd.crash_shell=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.crash_shell=">¶</a></dt><dd><p>Takes a boolean | |
| 14228c0d | 552 | argument. If <code class="option">true</code>, |
| 663996b3 | 553 | systemd spawns a shell when it |
| 14228c0d | 554 | crashes. Otherwise, no shell is |
| 663996b3 MS |
555 | spawned. Defaults to |
| 556 | <code class="option">false</code>, for security | |
| 557 | reasons, as the shell is not protected | |
| 558 | by any password | |
| 559 | authentication.</p></dd><dt id="systemd.crash_chvt="><span class="term"><code class="varname">systemd.crash_chvt=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.crash_chvt=">¶</a></dt><dd><p>Takes an integer | |
| 560 | argument. If positive systemd | |
| 561 | activates the specified virtual | |
| 562 | terminal when it crashes. Defaults to | |
| 14228c0d MB |
563 | <code class="constant">-1</code>.</p></dd><dt id="systemd.confirm_spawn="><span class="term"><code class="varname">systemd.confirm_spawn=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.confirm_spawn=">¶</a></dt><dd><p>Takes a boolean |
| 564 | argument. If <code class="option">true</code>, | |
| 663996b3 MS |
565 | asks for confirmation when spawning |
| 566 | processes. Defaults to | |
| 567 | <code class="option">false</code>.</p></dd><dt id="systemd.show_status="><span class="term"><code class="varname">systemd.show_status=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.show_status=">¶</a></dt><dd><p>Takes a boolean | |
| 14228c0d | 568 | argument. If <code class="option">true</code>, |
| 663996b3 MS |
569 | shows terse service status updates on |
| 570 | the console during bootup. Defaults to | |
| 571 | <code class="option">true</code>, unless | |
| 572 | <code class="option">quiet</code> is passed as | |
| 573 | kernel command line option in which | |
| 574 | case it defaults to | |
| 575 | <code class="option">false</code>.</p></dd><dt id="systemd.log_target="><span class="term"><code class="varname">systemd.log_target=</code>, </span><span class="term"><code class="varname">systemd.log_level=</code>, </span><span class="term"><code class="varname">systemd.log_color=</code>, </span><span class="term"><code class="varname">systemd.log_location=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.log_target=">¶</a></dt><dd><p>Controls log output, | |
| 576 | with the same effect as the | |
| 577 | <code class="varname">$SYSTEMD_LOG_TARGET</code>, <code class="varname">$SYSTEMD_LOG_LEVEL</code>, <code class="varname">$SYSTEMD_LOG_COLOR</code>, <code class="varname">$SYSTEMD_LOG_LOCATION</code> | |
| 578 | environment variables described above.</p></dd><dt id="systemd.default_standard_output="><span class="term"><code class="varname">systemd.default_standard_output=</code>, </span><span class="term"><code class="varname">systemd.default_standard_error=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.default_standard_output=">¶</a></dt><dd><p>Controls default | |
| 579 | standard output and error output for | |
| 580 | services, with the same effect as the | |
| 581 | <code class="option">--default-standard-output=</code> | |
| 582 | and <code class="option">--default-standard-error=</code> | |
| 583 | command line arguments described | |
| 584 | above, respectively.</p></dd><dt id="systemd.setenv="><span class="term"><code class="varname">systemd.setenv=</code></span><a class="headerlink" title="Permalink to this term" href="#systemd.setenv=">¶</a></dt><dd><p>Takes a string | |
| 14228c0d MB |
585 | argument in the form VARIABLE=VALUE. |
| 586 | May be used to set default environment | |
| 587 | variables to add to forked child processes. | |
| 588 | May be used more than once to set multiple | |
| 589 | variables.</p></dd><dt id="quiet"><span class="term"><code class="varname">quiet</code></span><a class="headerlink" title="Permalink to this term" href="#quiet">¶</a></dt><dd><p>Turn off | |
| 663996b3 MS |
590 | status output at boot, much like |
| 591 | <code class="varname">systemd.show_status=false</code> | |
| 592 | would. Note that this option is also | |
| 593 | read by the kernel itself and disables | |
| 14228c0d MB |
594 | kernel log output. Passing this option |
| 595 | hence turns off the usual output from | |
| 596 | both the system manager and the kernel. | |
| 597 | </p></dd><dt id="debug"><span class="term"><code class="varname">debug</code></span><a class="headerlink" title="Permalink to this term" href="#debug">¶</a></dt><dd><p>Turn on debugging | |
| 598 | output. This is equivalent to | |
| 599 | <code class="varname">systemd.log_level=debug</code>. | |
| 600 | Note that this option is also read by | |
| 601 | the kernel itself and enables kernel | |
| 602 | debug output. Passing this option | |
| 603 | hence turns on the debug output from | |
| 604 | both the system manager and the | |
| 663996b3 MS |
605 | kernel.</p></dd><dt id="emergency"><span class="term"><code class="varname">emergency</code></span><a class="headerlink" title="Permalink to this term" href="#emergency">¶</a></dt><dd><p>Boot into emergency |
| 606 | mode. This is equivalent to | |
| 607 | <code class="varname">systemd.unit=emergency.target</code> | |
| 608 | and provided for compatibility | |
| 609 | reasons and to be easier to type.</p></dd><dt id="single"><span class="term"><code class="varname">single</code>, </span><span class="term"><code class="varname">s</code>, </span><span class="term"><code class="varname">S</code>, </span><span class="term"><code class="varname">1</code></span><a class="headerlink" title="Permalink to this term" href="#single">¶</a></dt><dd><p>Boot into rescue | |
| 610 | mode. This is equivalent to | |
| 611 | <code class="varname">systemd.unit=rescue.target</code> | |
| 612 | and provided for compatibility reasons | |
| 613 | and to be easier to | |
| 614 | type.</p></dd><dt id="2"><span class="term"><code class="varname">2</code>, </span><span class="term"><code class="varname">3</code>, </span><span class="term"><code class="varname">4</code>, </span><span class="term"><code class="varname">5</code></span><a class="headerlink" title="Permalink to this term" href="#2">¶</a></dt><dd><p>Boot into the | |
| 615 | specified legacy SysV runlevel. These | |
| 616 | are equivalent to | |
| 617 | <code class="varname">systemd.unit=runlevel2.target</code>, | |
| 618 | <code class="varname">systemd.unit=runlevel3.target</code>, | |
| 619 | <code class="varname">systemd.unit=runlevel4.target</code>, | |
| 620 | and <code class="varname">systemd.unit=runlevel5.target</code>, respectively, | |
| 621 | and provided for compatibility reasons | |
| 622 | and to be easier to | |
| 623 | type.</p></dd><dt id="locale.LANG="><span class="term"><code class="varname">locale.LANG=</code>, </span><span class="term"><code class="varname">locale.LANGUAGE=</code>, </span><span class="term"><code class="varname">locale.LC_CTYPE=</code>, </span><span class="term"><code class="varname">locale.LC_NUMERIC=</code>, </span><span class="term"><code class="varname">locale.LC_TIME=</code>, </span><span class="term"><code class="varname">locale.LC_COLLATE=</code>, </span><span class="term"><code class="varname">locale.LC_MONETARY=</code>, </span><span class="term"><code class="varname">locale.LC_MESSAGES=</code>, </span><span class="term"><code class="varname">locale.LC_PAPER=</code>, </span><span class="term"><code class="varname">locale.LC_NAME=</code>, </span><span class="term"><code class="varname">locale.LC_ADDRESS=</code>, </span><span class="term"><code class="varname">locale.LC_TELEPHONE=</code>, </span><span class="term"><code class="varname">locale.LC_MEASUREMENT=</code>, </span><span class="term"><code class="varname">locale.LC_IDENTIFICATION=</code></span><a class="headerlink" title="Permalink to this term" href="#locale.LANG=">¶</a></dt><dd><p>Set the system locale | |
| 624 | to use. This overrides the settings in | |
| 625 | <code class="filename">/etc/locale.conf</code>. For | |
| 626 | more information see | |
| 627 | <a href="locale.conf.html"><span class="citerefentry"><span class="refentrytitle">locale.conf</span>(5)</span></a> | |
| 628 | and | |
| 629 | <a href="locale.html"><span class="citerefentry"><span class="refentrytitle">locale</span>(7)</span></a>. | |
| 630 | </p></dd></dl></div><p>For other kernel command line parameters | |
| 631 | understood by components of the core OS, please refer | |
| 632 | to | |
| 14228c0d | 633 | <a href="kernel-command-line.html"><span class="citerefentry"><span class="refentrytitle">kernel-command-line</span>(7)</span></a>.</p></div><div class="refsect1"><a name="idm274693177056"></a><h2 id="Sockets and FIFOs">Sockets and FIFOs<a class="headerlink" title="Permalink to this headline" href="#Sockets%20and%20FIFOs">¶</a></h2><div class="variablelist"><dl class="variablelist"><dt id="/run/systemd/notify"><span class="term"><code class="filename">/run/systemd/notify</code></span><a class="headerlink" title="Permalink to this term" href="#/run/systemd/notify">¶</a></dt><dd><p>Daemon status |
| 663996b3 | 634 | notification socket. This is an |
| 14228c0d | 635 | <code class="constant">AF_UNIX</code> datagram socket and is used to |
| 663996b3 MS |
636 | implement the daemon notification |
| 637 | logic as implemented by | |
| 638 | <a href="sd_notify.html"><span class="citerefentry"><span class="refentrytitle">sd_notify</span>(3)</span></a>.</p></dd><dt id="/run/systemd/shutdownd"><span class="term"><code class="filename">/run/systemd/shutdownd</code></span><a class="headerlink" title="Permalink to this term" href="#/run/systemd/shutdownd">¶</a></dt><dd><p>Used internally by the | |
| 639 | <a href="shutdown.html"><span class="citerefentry"><span class="refentrytitle">shutdown</span>(8)</span></a> | |
| 640 | tool to implement delayed | |
| 14228c0d | 641 | shutdowns. This is an <code class="constant">AF_UNIX</code> datagram |
| 663996b3 MS |
642 | socket.</p></dd><dt id="/run/systemd/private"><span class="term"><code class="filename">/run/systemd/private</code></span><a class="headerlink" title="Permalink to this term" href="#/run/systemd/private">¶</a></dt><dd><p>Used internally as |
| 643 | communication channel between | |
| 644 | <a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a> | |
| 645 | and the systemd process. This is an | |
| 14228c0d | 646 | <code class="constant">AF_UNIX</code> stream socket. This interface |
| 663996b3 MS |
647 | is private to systemd and should not |
| 648 | be used in external | |
| 649 | projects.</p></dd><dt id="/dev/initctl"><span class="term"><code class="filename">/dev/initctl</code></span><a class="headerlink" title="Permalink to this term" href="#/dev/initctl">¶</a></dt><dd><p>Limited compatibility | |
| 650 | support for the SysV client interface, | |
| 651 | as implemented by the | |
| 652 | <code class="filename">systemd-initctl.service</code> | |
| 653 | unit. This is a named pipe in the file | |
| 654 | system. This interface is obsolete and | |
| 655 | should not be used in new | |
| 14228c0d MB |
656 | applications.</p></dd></dl></div></div><div class="refsect1"><a name="idm274693163872"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also">¶</a></h2><p> |
| 657 | The <a class="ulink" href="http://www.freedesktop.org/wiki/Software/systemd/" target="_top">systemd Homepage</a>, | |
| 663996b3 MS |
658 | <a href="systemd-system.conf.html"><span class="citerefentry"><span class="refentrytitle">systemd-system.conf</span>(5)</span></a>, |
| 659 | <a href="locale.conf.html"><span class="citerefentry"><span class="refentrytitle">locale.conf</span>(5)</span></a>, | |
| 660 | <a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>, | |
| 661 | <a href="journalctl.html"><span class="citerefentry"><span class="refentrytitle">journalctl</span>(1)</span></a>, | |
| 662 | <a href="systemd-notify.html"><span class="citerefentry"><span class="refentrytitle">systemd-notify</span>(1)</span></a>, | |
| 663 | <a href="daemon.html"><span class="citerefentry"><span class="refentrytitle">daemon</span>(7)</span></a>, | |
| 664 | <a href="sd-daemon.html"><span class="citerefentry"><span class="refentrytitle">sd-daemon</span>(3)</span></a>, | |
| 665 | <a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>, | |
| 666 | <a href="systemd.special.html"><span class="citerefentry"><span class="refentrytitle">systemd.special</span>(5)</span></a>, | |
| 667 | <a href="pkg-config.html"><span class="citerefentry"><span class="refentrytitle">pkg-config</span>(1)</span></a>, | |
| 668 | <a href="kernel-command-line.html"><span class="citerefentry"><span class="refentrytitle">kernel-command-line</span>(7)</span></a>, | |
| 669 | <a href="bootup.html"><span class="citerefentry"><span class="refentrytitle">bootup</span>(7)</span></a>, | |
| 670 | <a href="systemd.directives.html"><span class="citerefentry"><span class="refentrytitle">systemd.directives</span>(7)</span></a> | |
| 14228c0d | 671 | </p></div><div class="footnotes"><br><hr style="width:100; text-align:left;margin-left: 0"><div id="ftn.idm274693234912" class="footnote"><p><a href="#idm274693234912" class="para"><sup class="para">[1] </sup></a>If run inside a Linux |
| 663996b3 MS |
672 | container these arguments may be passed as command |
| 673 | line arguments to systemd itself, next to any of the | |
| 674 | command line options listed in the Options section | |
| 675 | above. If run outside of Linux containers, these | |
| 676 | arguments are parsed from | |
| 677 | <code class="filename">/proc/cmdline</code> | |
| 678 | instead.</p></div></div></div></body></html> |