man/systemctl.xml

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  11   Copyright 2010 Lennart Poettering
  12
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  26
  27 <refentry id="systemctl"
  28           xmlns:xi="http://www.w3.org/2001/XInclude">
  29
  30   <refentryinfo>
  31     <title>systemctl</title>
  32     <productname>systemd</productname>
  33
  34     <authorgroup>
  35       <author>
  36         <contrib>Developer</contrib>
  37         <firstname>Lennart</firstname>
  38         <surname>Poettering</surname>
  39         <email>lennart@poettering.net</email>
  40       </author>
  41     </authorgroup>
  42   </refentryinfo>
  43
  44   <refmeta>
  45     <refentrytitle>systemctl</refentrytitle>
  46     <manvolnum>1</manvolnum>
  47   </refmeta>
  48
  49   <refnamediv>
  50     <refname>systemctl</refname>
  51     <refpurpose>Control the systemd system and service manager</refpurpose>
  52   </refnamediv>
  53
  54   <refsynopsisdiv>
  55     <cmdsynopsis>
  56       <command>systemctl</command>
  57       <arg choice="opt" rep="repeat">OPTIONS</arg>
  58       <arg choice="plain">COMMAND</arg>
  59       <arg choice="opt" rep="repeat">NAME</arg>
  60     </cmdsynopsis>
  61   </refsynopsisdiv>
  62
  63   <refsect1>
  64     <title>Description</title>
  65
  66     <para><command>systemctl</command> may be used to introspect and
  67     control the state of the <literal>systemd</literal> system and
  68     service manager. Please refer to
  69     <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  70     for an introduction into the basic concepts and functionality this
  71     tool manages.</para>
  72   </refsect1>
  73
  74   <refsect1>
  75     <title>Options</title>
  76
  77     <para>The following options are understood:</para>
  78
  79     <variablelist>
  80       <varlistentry>
  81         <term><option>-t</option></term>
  82         <term><option>--type=</option></term>
  83
  84         <listitem>
  85           <para>The argument should be a comma-separated list of unit
  86           types such as <option>service</option> and
  87           <option>socket</option>.
  88           </para>
  89
  90           <para>If one of the arguments is a unit type, when listing
  91           units, limit display to certain unit types. Otherwise, units
  92           of all types will be shown.</para>
  93
  94           <para>As a special case, if one of the arguments is
  95           <option>help</option>, a list of allowed values will be
  96           printed and the program will exit.</para>
  97         </listitem>
  98       </varlistentry>
  99
 100       <varlistentry>
 101         <term><option>--state=</option></term>
 102
 103         <listitem>
 104         <para>The argument should be a comma-separated list of unit
 105         LOAD, SUB, or ACTIVE states. When listing units, show only
 106         those in specified states. Use <option>--state=failed</option>
 107         to show only failed units.</para>
 108         </listitem>
 109       </varlistentry>
 110
 111       <varlistentry>
 112         <term><option>-p</option></term>
 113         <term><option>--property=</option></term>
 114
 115         <listitem>
 116           <para>When showing unit/job/manager properties with the
 117           <command>show</command> command, limit display to certain
 118           properties as specified as argument. If not specified, all
 119           set properties are shown. The argument should be a
 120           comma-separated list of property names, such as
 121           <literal>MainPID</literal>. If specified more than once, all
 122           properties with the specified names are shown.</para>
 123         </listitem>
 124       </varlistentry>
 125
 126       <varlistentry>
 127         <term><option>-a</option></term>
 128         <term><option>--all</option></term>
 129
 130         <listitem>
 131           <para>When listing units, show all loaded units, regardless
 132           of their state, including inactive units. When showing
 133           unit/job/manager properties, show all properties regardless
 134           whether they are set or not.</para>
 135           <para>To list all units installed on the system, use the
 136           <command>list-unit-files</command> command instead.</para>
 137         </listitem>
 138       </varlistentry>
 139
 140       <varlistentry>
 141         <term><option>-r</option></term>
 142         <term><option>--recursive</option></term>
 143
 144         <listitem>
 145           <para>When listing units, also show units of local
 146           containers. Units of local containers will be prefixed with
 147           the container name, separated by a single colon character
 148           (<literal>:</literal>).</para>
 149         </listitem>
 150       </varlistentry>
 151
 152       <varlistentry>
 153         <term><option>--reverse</option></term>
 154
 155         <listitem>
 156           <para>Show reverse dependencies between units with
 157           <command>list-dependencies</command>, i.e. follow
 158           dependencies of type <varname>WantedBy=</varname>,
 159           <varname>RequiredBy=</varname>,
 160           <varname>RequiredByOverridable=</varname>,
 161           <varname>PartOf=</varname>, <varname>BoundBy=</varname>,
 162           instead of <varname>Wants=</varname> and similar.
 163           </para>
 164         </listitem>
 165       </varlistentry>
 166
 167       <varlistentry>
 168         <term><option>--after</option></term>
 169
 170         <listitem>
 171           <para>With <command>list-dependencies</command>, show the
 172           units that are ordered before the specified unit. In other
 173           words, recursively list units following the
 174           <varname>After=</varname> dependency.</para>
 175
 176           <para>Note that any <varname>After=</varname> dependency is
 177           automatically mirrored to create a
 178           <varname>Before=</varname> dependency. Temporal dependencies
 179           may be specified explicitly, but are also created implicitly
 180           for units which are <varname>WantedBy=</varname> targets
 181           (see
 182           <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>),
 183           and as a result of other directives (for example
 184           <varname>RequiresMountsFor=</varname>). Both explicitly
 185           and implicitly introduced dependencies are shown with
 186           <command>list-dependencies</command>.</para>
 187         </listitem>
 188       </varlistentry>
 189
 190       <varlistentry>
 191         <term><option>--before</option></term>
 192
 193         <listitem>
 194           <para>With <command>list-dependencies</command>, show the
 195           units that are ordered after the specified unit. In other
 196           words, recursively list units following the
 197           <varname>Before=</varname> dependency.</para>
 198         </listitem>
 199       </varlistentry>
 200
 201       <varlistentry>
 202         <term><option>-l</option></term>
 203         <term><option>--full</option></term>
 204
 205         <listitem>
 206           <para>Do not ellipsize unit names, process tree entries,
 207           journal output, or truncate unit descriptions in the output
 208           of <command>status</command>, <command>list-units</command>,
 209           <command>list-jobs</command>, and
 210           <command>list-timers</command>.</para>
 211         </listitem>
 212       </varlistentry>
 213
 214       <varlistentry>
 215         <term><option>--show-types</option></term>
 216
 217         <listitem>
 218           <para>When showing sockets, show the type of the socket.</para>
 219         </listitem>
 220       </varlistentry>
 221
 222       <varlistentry>
 223         <term><option>--job-mode=</option></term>
 224
 225         <listitem>
 226         <para>When queuing a new job, this option controls how to deal with
 227         already queued jobs. It takes one of <literal>fail</literal>,
 228         <literal>replace</literal>,
 229         <literal>replace-irreversibly</literal>,
 230         <literal>isolate</literal>,
 231         <literal>ignore-dependencies</literal>,
 232         <literal>ignore-requirements</literal> or
 233         <literal>flush</literal>. Defaults to
 234         <literal>replace</literal>, except when the
 235         <command>isolate</command> command is used which implies the
 236         <literal>isolate</literal> job mode.</para>
 237
 238         <para>If <literal>fail</literal> is specified and a requested
 239         operation conflicts with a pending job (more specifically:
 240         causes an already pending start job to be reversed into a stop
 241         job or vice versa), cause the operation to fail.</para>
 242
 243         <para>If <literal>replace</literal> (the default) is
 244         specified, any conflicting pending job will be replaced, as
 245         necessary.</para>
 246
 247         <para>If <literal>replace-irreversibly</literal> is specified,
 248         operate like <literal>replace</literal>, but also mark the new
 249         jobs as irreversible. This prevents future conflicting
 250         transactions from replacing these jobs (or even being enqueued
 251         while the irreversible jobs are still pending). Irreversible
 252         jobs can still be cancelled using the <command>cancel</command>
 253         command.</para>
 254
 255         <para><literal>isolate</literal> is only valid for start
 256         operations and causes all other units to be stopped when the
 257         specified unit is started. This mode is always used when the
 258         <command>isolate</command> command is used.</para>
 259
 260         <para><literal>flush</literal> will cause all queued jobs to
 261         be canceled when the new job is enqueued.</para>
 262
 263         <para>If <literal>ignore-dependencies</literal> is specified,
 264         then all unit dependencies are ignored for this new job and
 265         the operation is executed immediately. If passed, no required
 266         units of the unit passed will be pulled in, and no ordering
 267         dependencies will be honored. This is mostly a debugging and
 268         rescue tool for the administrator and should not be used by
 269         applications.</para>
 270
 271         <para><literal>ignore-requirements</literal> is similar to
 272         <literal>ignore-dependencies</literal>, but only causes the
 273         requirement dependencies to be ignored, the ordering
 274         dependencies will still be honoured.</para>
 275         </listitem>
 276
 277       </varlistentry>
 278
 279       <varlistentry>
 280         <term><option>-i</option></term>
 281         <term><option>--ignore-inhibitors</option></term>
 282
 283         <listitem>
 284           <para>When system shutdown or a sleep state is requested,
 285           ignore inhibitor locks. Applications can establish inhibitor
 286           locks to avoid that certain important operations (such as CD
 287           burning or suchlike) are interrupted by system shutdown or a
 288           sleep state. Any user may take these locks and privileged
 289           users may override these locks. If any locks are taken,
 290           shutdown and sleep state requests will normally fail
 291           (regardless of whether privileged or not) and a list of active locks
 292           is printed. However, if <option>--ignore-inhibitors</option>
 293           is specified, the locks are ignored and not printed, and the
 294           operation attempted anyway, possibly requiring additional
 295           privileges.</para>
 296         </listitem>
 297       </varlistentry>
 298
 299       <varlistentry>
 300         <term><option>-q</option></term>
 301         <term><option>--quiet</option></term>
 302
 303         <listitem>
 304           <para>Suppress output to standard output in
 305           <command>snapshot</command>,
 306           <command>is-active</command>,
 307           <command>is-failed</command>,
 308           <command>is-enabled</command>,
 309           <command>is-system-running</command>,
 310           <command>enable</command> and
 311         <command>disable</command>.</para>
 312         </listitem>
 313       </varlistentry>
 314
 315       <varlistentry>
 316         <term><option>--no-block</option></term>
 317
 318         <listitem>
 319           <para>Do not synchronously wait for the requested operation
 320           to finish. If this is not specified, the job will be
 321           verified, enqueued and <command>systemctl</command> will
 322           wait until the unit's start-up is completed. By passing this
 323           argument, it is only verified and enqueued.</para>
 324         </listitem>
 325       </varlistentry>
 326
 327       <xi:include href="user-system-options.xml" xpointer="user" />
 328       <xi:include href="user-system-options.xml" xpointer="system" />
 329
 330       <!-- we do not document -failed here, as it has been made
 331            redundant by -state=failed, which it predates. To keep
 332            things simple we only document the new switch, while
 333            keeping the old one around for compatibility only. -->
 334
 335       <varlistentry>
 336         <term><option>--no-wall</option></term>
 337
 338         <listitem>
 339           <para>Do not send wall message before halt, power-off,
 340           reboot.</para>
 341         </listitem>
 342       </varlistentry>
 343
 344       <varlistentry>
 345         <term><option>--global</option></term>
 346
 347         <listitem>
 348           <para>When used with <command>enable</command> and
 349           <command>disable</command>, operate on the global user
 350           configuration directory, thus enabling or disabling a unit
 351           file globally for all future logins of all users.</para>
 352         </listitem>
 353       </varlistentry>
 354
 355       <varlistentry>
 356         <term><option>--no-reload</option></term>
 357
 358         <listitem>
 359           <para>When used with <command>enable</command> and
 360           <command>disable</command>, do not implicitly reload daemon
 361           configuration after executing the changes.</para>
 362         </listitem>
 363       </varlistentry>
 364
 365       <varlistentry>
 366         <term><option>--no-ask-password</option></term>
 367
 368         <listitem>
 369           <para>When used with <command>start</command> and related
 370           commands, disables asking for passwords. Background services
 371           may require input of a password or passphrase string, for
 372           example to unlock system hard disks or cryptographic
 373           certificates. Unless this option is specified and the
 374           command is invoked from a terminal,
 375           <command>systemctl</command> will query the user on the
 376           terminal for the necessary secrets. Use this option to
 377           switch this behavior off. In this case, the password must be
 378           supplied by some other means (for example graphical password
 379           agents) or the service might fail. This also disables
 380           querying the user for authentication for privileged
 381           operations.</para>
 382         </listitem>
 383       </varlistentry>
 384
 385       <varlistentry>
 386         <term><option>--kill-who=</option></term>
 387
 388         <listitem>
 389           <para>When used with <command>kill</command>, choose which
 390           processes to send a signal to. Must be one of
 391           <option>main</option>, <option>control</option> or
 392           <option>all</option> to select whether to kill only the main
 393           process, the control process or all processes of the
 394           unit. The main process of the unit is the one that defines
 395           the life-time of it. A control process of a unit is one that
 396           is invoked by the manager to induce state changes of it. For
 397           example, all processes started due to the
 398           <varname>ExecStartPre=</varname>,
 399           <varname>ExecStop=</varname> or
 400           <varname>ExecReload=</varname> settings of service units are
 401           control processes. Note that there is only one control
 402           process per unit at a time, as only one state change is
 403           executed at a time. For services of type
 404           <varname>Type=forking</varname>, the initial process started
 405           by the manager for <varname>ExecStart=</varname> is a
 406           control process, while the process ultimately forked off by
 407           that one is then considered the main process of the unit (if
 408           it can be determined). This is different for service units
 409           of other types, where the process forked off by the manager
 410           for <varname>ExecStart=</varname> is always the main process
 411           itself. A service unit consists of zero or one main process,
 412           zero or one control process plus any number of additional
 413           processes. Not all unit types manage processes of these
 414           types however. For example, for mount units, control processes
 415           are defined (which are the invocations of
 416           <filename>&MOUNT_PATH;</filename> and
 417           <filename>&UMOUNT_PATH;</filename>), but no main process
 418           is defined. If omitted, defaults to
 419           <option>all</option>.</para>
 420         </listitem>
 421
 422       </varlistentry>
 423
 424       <varlistentry>
 425         <term><option>-s</option></term>
 426         <term><option>--signal=</option></term>
 427
 428         <listitem>
 429           <para>When used with <command>kill</command>, choose which
 430           signal to send to selected processes. Must be one of the
 431           well known signal specifiers such as <constant>SIGTERM</constant>, <constant>SIGINT</constant> or
 432           <constant>SIGSTOP</constant>. If omitted, defaults to
 433           <option>SIGTERM</option>.</para>
 434         </listitem>
 435       </varlistentry>
 436
 437       <varlistentry>
 438         <term><option>-f</option></term>
 439         <term><option>--force</option></term>
 440
 441         <listitem>
 442           <para>When used with <command>enable</command>, overwrite
 443           any existing conflicting symlinks.</para>
 444
 445           <para>When used with <command>halt</command>,
 446           <command>poweroff</command>, <command>reboot</command> or
 447           <command>kexec</command>, execute the selected operation
 448           without shutting down all units. However, all processes will
 449           be killed forcibly and all file systems are unmounted or
 450           remounted read-only. This is hence a drastic but relatively
 451           safe option to request an immediate reboot. If
 452           <option>--force</option> is specified twice for these
 453           operations, they will be executed immediately without
 454           terminating any processes or unmounting any file
 455           systems. Warning: specifying <option>--force</option> twice
 456           with any of these operations might result in data
 457           loss.</para>
 458         </listitem>
 459       </varlistentry>
 460
 461       <varlistentry>
 462         <term><option>--now</option></term>
 463
 464         <listitem>
 465           <para>When used with <command>enable</command>, the units
 466           will also be started. When used with <command>disable</command> or
 467           <command>mask</command>, the units will also be stopped. The start
 468           or stop operation is only carried out when the respective enable or
 469           disable operation has been successful.</para>
 470         </listitem>
 471       </varlistentry>
 472
 473       <varlistentry>
 474         <term><option>--root=</option></term>
 475
 476         <listitem>
 477           <para>When used with
 478           <command>enable</command>/<command>disable</command>/<command>is-enabled</command>
 479           (and related commands), use alternative root path when
 480           looking for unit files.</para>
 481         </listitem>
 482
 483       </varlistentry>
 484
 485       <varlistentry>
 486         <term><option>--runtime</option></term>
 487
 488         <listitem>
 489           <para>When used with <command>enable</command>,
 490           <command>disable</command>, <command>edit</command>,
 491           (and related commands), make changes only temporarily, so
 492           that they are lost on the next reboot. This will have the
 493           effect that changes are not made in subdirectories of
 494           <filename>/etc</filename> but in <filename>/run</filename>,
 495           with identical immediate effects, however, since the latter
 496           is lost on reboot, the changes are lost too.</para>
 497
 498           <para>Similarly, when used with
 499           <command>set-property</command>, make changes only
 500           temporarily, so that they are lost on the next
 501           reboot.</para>
 502         </listitem>
 503       </varlistentry>
 504
 505       <varlistentry>
 506         <term><option>--preset-mode=</option></term>
 507
 508         <listitem>
 509           <para>Takes one of <literal>full</literal> (the default),
 510           <literal>enable-only</literal>,
 511           <literal>disable-only</literal>. When used with the
 512           <command>preset</command> or <command>preset-all</command>
 513           commands, controls whether units shall be disabled and
 514           enabled according to the preset rules, or only enabled, or
 515           only disabled.</para>
 516         </listitem>
 517       </varlistentry>
 518
 519       <varlistentry>
 520         <term><option>-n</option></term>
 521         <term><option>--lines=</option></term>
 522
 523         <listitem>
 524           <para>When used with <command>status</command>, controls the
 525           number of journal lines to show, counting from the most
 526           recent ones. Takes a positive integer argument. Defaults to
 527           10.</para>
 528         </listitem>
 529       </varlistentry>
 530
 531       <varlistentry>
 532         <term><option>-o</option></term>
 533         <term><option>--output=</option></term>
 534
 535         <listitem>
 536           <para>When used with <command>status</command>, controls the
 537           formatting of the journal entries that are shown. For the
 538           available choices, see
 539           <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
 540           Defaults to <literal>short</literal>.</para>
 541         </listitem>
 542       </varlistentry>
 543
 544       <varlistentry>
 545         <term><option>--firmware-setup</option></term>
 546
 547         <listitem>
 548           <para>When used with the <command>reboot</command> command,
 549           indicate to the system's firmware to boot into setup
 550           mode. Note that this is currently only supported on some EFI
 551           systems and only if the system was booted in EFI
 552           mode.</para>
 553         </listitem>
 554       </varlistentry>
 555
 556       <varlistentry>
 557         <term><option>--plain</option></term>
 558
 559         <listitem>
 560           <para>When used with <command>list-dependencies</command>,
 561           the output is printed as a list instead of a tree.</para>
 562         </listitem>
 563       </varlistentry>
 564
 565       <xi:include href="user-system-options.xml" xpointer="host" />
 566       <xi:include href="user-system-options.xml" xpointer="machine" />
 567
 568       <xi:include href="standard-options.xml" xpointer="no-pager" />
 569       <xi:include href="standard-options.xml" xpointer="no-legend" />
 570       <xi:include href="standard-options.xml" xpointer="help" />
 571       <xi:include href="standard-options.xml" xpointer="version" />
 572     </variablelist>
 573   </refsect1>
 574
 575   <refsect1>
 576     <title>Commands</title>
 577
 578     <para>The following commands are understood:</para>
 579
 580     <refsect2>
 581       <title>Unit Commands</title>
 582
 583       <variablelist>
 584         <varlistentry>
 585           <term><command>list-units <optional><replaceable>PATTERN</replaceable>...</optional></command></term>
 586
 587           <listitem>
 588             <para>List known units (subject to limitations specified
 589             with <option>-t</option>). If one or more
 590             <replaceable>PATTERN</replaceable>s are specified, only
 591             units matching one of them are shown.</para>
 592
 593             <para>This is the default command.</para>
 594           </listitem>
 595         </varlistentry>
 596
 597         <varlistentry>
 598           <term><command>list-sockets <optional><replaceable>PATTERN</replaceable>...</optional></command></term>
 599
 600           <listitem>
 601             <para>List socket units ordered by listening address.
 602             If one or more <replaceable>PATTERN</replaceable>s are
 603             specified, only socket units matching one of them are
 604             shown. Produces output similar to
 605             <programlisting>
 606 LISTEN           UNIT                        ACTIVATES
 607 /dev/initctl     systemd-initctl.socket      systemd-initctl.service
 608 ...
 609 [::]:22          sshd.socket                 sshd.service
 610 kobject-uevent 1 systemd-udevd-kernel.socket systemd-udevd.service
 611
 612 5 sockets listed.</programlisting>
 613             Note: because the addresses might contains spaces, this output
 614             is not suitable for programmatic consumption.
 615             </para>
 616
 617             <para>See also the options <option>--show-types</option>,
 618             <option>--all</option>, and <option>--state=</option>.</para>
 619           </listitem>
 620         </varlistentry>
 621
 622         <varlistentry>
 623           <term><command>list-timers <optional><replaceable>PATTERN</replaceable>...</optional></command></term>
 624
 625           <listitem>
 626             <para>List timer units ordered by the time they elapse
 627             next. If one or more <replaceable>PATTERN</replaceable>s
 628             are specified, only units matching one of them are shown.
 629             </para>
 630
 631             <para>See also the options <option>--all</option> and
 632             <option>--state=</option>.</para>
 633           </listitem>
 634         </varlistentry>
 635
 636         <varlistentry>
 637           <term><command>start <replaceable>PATTERN</replaceable>...</command></term>
 638
 639           <listitem>
 640             <para>Start (activate) one or more units specified on the
 641             command line.</para>
 642
 643             <para>Note that glob patterns operate on a list of currently
 644             loaded units. Units which are not active and are not in a
 645             failed state usually are not loaded, and would not be
 646             matched by any pattern. In addition, in case of
 647             instantiated units, systemd is often unaware of the
 648             instance name until the instance has been started. Therefore,
 649             using glob patterns with <command>start</command>
 650             has limited usefulness.</para>
 651           </listitem>
 652         </varlistentry>
 653         <varlistentry>
 654           <term><command>stop <replaceable>PATTERN</replaceable>...</command></term>
 655
 656           <listitem>
 657             <para>Stop (deactivate) one or more units specified on the
 658             command line.</para>
 659           </listitem>
 660         </varlistentry>
 661         <varlistentry>
 662           <term><command>reload <replaceable>PATTERN</replaceable>...</command></term>
 663
 664           <listitem>
 665             <para>Asks all units listed on the command line to reload
 666             their configuration. Note that this will reload the
 667             service-specific configuration, not the unit configuration
 668             file of systemd. If you want systemd to reload the
 669             configuration file of a unit, use the
 670             <command>daemon-reload</command> command. In other words:
 671             for the example case of Apache, this will reload Apache's
 672             <filename>httpd.conf</filename> in the web server, not the
 673             <filename>apache.service</filename> systemd unit
 674             file.</para>
 675
 676             <para>This command should not be confused with the
 677             <command>daemon-reload</command> command.</para>
 678           </listitem>
 679
 680         </varlistentry>
 681         <varlistentry>
 682           <term><command>restart <replaceable>PATTERN</replaceable>...</command></term>
 683
 684           <listitem>
 685             <para>Restart one or more units specified on the command
 686             line. If the units are not running yet, they will be
 687             started.</para>
 688           </listitem>
 689         </varlistentry>
 690         <varlistentry>
 691           <term><command>try-restart <replaceable>PATTERN</replaceable>...</command></term>
 692
 693           <listitem>
 694             <para>Restart one or more units specified on the command
 695             line if the units are running. This does nothing if units are not
 696             running.  Note that, for compatibility with Red Hat init
 697             scripts, <command>condrestart</command> is equivalent to this
 698             command.</para>
 699           </listitem>
 700         </varlistentry>
 701         <varlistentry>
 702           <term><command>reload-or-restart <replaceable>PATTERN</replaceable>...</command></term>
 703
 704           <listitem>
 705             <para>Reload one or more units if they support it. If not,
 706             restart them instead. If the units are not running yet, they
 707             will be started.</para>
 708           </listitem>
 709         </varlistentry>
 710         <varlistentry>
 711           <term><command>reload-or-try-restart <replaceable>PATTERN</replaceable>...</command></term>
 712
 713           <listitem>
 714             <para>Reload one or more units if they support it. If not,
 715             restart them instead. This does nothing if the units are not
 716             running. Note that, for compatibility with SysV init scripts,
 717             <command>force-reload</command> is equivalent to this
 718             command.</para>
 719           </listitem>
 720         </varlistentry>
 721         <varlistentry>
 722           <term><command>isolate <replaceable>NAME</replaceable></command></term>
 723
 724           <listitem>
 725             <para>Start the unit specified on the command line and its
 726             dependencies and stop all others. If a unit name with no
 727             extension is given, an extension of
 728             <literal>.target</literal> will be assumed.</para>
 729
 730             <para>This is similar to changing the runlevel in a
 731             traditional init system. The <command>isolate</command>
 732             command will immediately stop processes that are not enabled
 733             in the new unit, possibly including the graphical
 734             environment or terminal you are currently using.</para>
 735
 736             <para>Note that this is allowed only on units where
 737             <option>AllowIsolate=</option> is enabled. See
 738             <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 739             for details.</para>
 740           </listitem>
 741         </varlistentry>
 742         <varlistentry>
 743           <term><command>kill <replaceable>PATTERN</replaceable>...</command></term>
 744
 745           <listitem>
 746             <para>Send a signal to one or more processes of the
 747             unit. Use <option>--kill-who=</option> to select which
 748             process to kill. Use <option>--signal=</option> to select
 749             the signal to send.</para>
 750           </listitem>
 751         </varlistentry>
 752         <varlistentry>
 753           <term><command>is-active <replaceable>PATTERN</replaceable>...</command></term>
 754
 755           <listitem>
 756             <para>Check whether any of the specified units are active
 757             (i.e. running). Returns an exit code
 758             <constant>0</constant> if at least one is active, or
 759             non-zero otherwise. Unless <option>--quiet</option> is
 760             specified, this will also print the current unit state to
 761             standard output.</para>
 762           </listitem>
 763         </varlistentry>
 764         <varlistentry>
 765           <term><command>is-failed <replaceable>PATTERN</replaceable>...</command></term>
 766
 767           <listitem>
 768             <para>Check whether any of the specified units are in a
 769             "failed" state. Returns an exit code
 770             <constant>0</constant> if at least one has failed,
 771             non-zero otherwise. Unless <option>--quiet</option> is
 772             specified, this will also print the current unit state to
 773             standard output.</para>
 774           </listitem>
 775         </varlistentry>
 776         <varlistentry>
 777           <term><command>status</command> <optional><replaceable>PATTERN</replaceable>...|<replaceable>PID</replaceable>...]</optional></term>
 778
 779           <listitem>
 780             <para>Show terse runtime status information about one or
 781             more units, followed by most recent log data from the
 782             journal. If no units are specified, show system status. If
 783             combined with <option>--all</option>, also show the status of
 784             all units (subject to limitations specified with
 785             <option>-t</option>). If a PID is passed, show information
 786             about the unit the process belongs to.</para>
 787
 788             <para>This function is intended to generate human-readable
 789             output. If you are looking for computer-parsable output,
 790             use <command>show</command> instead. By default this
 791             function only shows 10 lines of output and ellipsizes
 792             lines to fit in the terminal window. This can be changes
 793             with <option>--lines</option> and <option>--full</option>,
 794             see above. In addition, <command>journalctl
 795             --unit=<replaceable>NAME</replaceable></command> or
 796             <command>journalctl
 797             --user-unit=<replaceable>NAME</replaceable></command> use
 798             a similar filter for messages and might be more
 799             convenient.
 800             </para>
 801           </listitem>
 802         </varlistentry>
 803         <varlistentry>
 804           <term><command>show</command> <optional><replaceable>PATTERN</replaceable>...|<replaceable>JOB</replaceable>...</optional></term>
 805
 806           <listitem>
 807             <para>Show properties of one or more units, jobs, or the
 808             manager itself. If no argument is specified, properties of
 809             the manager will be shown. If a unit name is specified,
 810             properties of the unit is shown, and if a job id is
 811             specified, properties of the job is shown. By default, empty
 812             properties are suppressed. Use <option>--all</option> to
 813             show those too. To select specific properties to show, use
 814             <option>--property=</option>. This command is intended to be
 815             used whenever computer-parsable output is required. Use
 816             <command>status</command> if you are looking for formatted
 817             human-readable output.</para>
 818           </listitem>
 819         </varlistentry>
 820         <varlistentry>
 821           <term><command>cat <replaceable>PATTERN</replaceable>...</command></term>
 822
 823           <listitem>
 824             <para>Show backing files of one or more units. Prints the
 825             "fragment" and "drop-ins" (source files) of units. Each
 826             file is preceded by a comment which includes the file
 827             name.</para>
 828           </listitem>
 829         </varlistentry>
 830         <varlistentry>
 831           <term><command>set-property <replaceable>NAME</replaceable> <replaceable>ASSIGNMENT</replaceable>...</command></term>
 832
 833           <listitem>
 834             <para>Set the specified unit properties at runtime where
 835             this is supported. This allows changing configuration
 836             parameter properties such as resource control settings at
 837             runtime. Not all properties may be changed at runtime, but
 838             many resource control settings (primarily those in
 839             <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>)
 840             may. The changes are applied instantly, and stored on disk
 841             for future boots, unless <option>--runtime</option> is
 842             passed, in which case the settings only apply until the
 843             next reboot. The syntax of the property assignment follows
 844             closely the syntax of assignments in unit files.</para>
 845
 846             <para>Example: <command>systemctl set-property foobar.service CPUShares=777</command></para>
 847
 848             <para>Note that this command allows changing multiple
 849             properties at the same time, which is preferable over
 850             setting them individually. Like unit file configuration
 851             settings, assigning the empty list to list parameters will
 852             reset the list.</para>
 853           </listitem>
 854         </varlistentry>
 855
 856         <varlistentry>
 857           <term><command>help <replaceable>PATTERN</replaceable>...|<replaceable>PID</replaceable>...</command></term>
 858
 859           <listitem>
 860             <para>Show manual pages for one or more units, if
 861             available. If a PID is given, the manual pages for the unit
 862             the process belongs to are shown.</para>
 863           </listitem>
 864         </varlistentry>
 865
 866         <varlistentry>
 867           <term><command>reset-failed [<replaceable>PATTERN</replaceable>...]</command></term>
 868
 869           <listitem>
 870             <para>Reset the <literal>failed</literal> state of the
 871             specified units, or if no unit name is passed, reset the state of all
 872             units. When a unit fails in some way (i.e. process exiting
 873             with non-zero error code, terminating abnormally or timing
 874             out), it will automatically enter the
 875             <literal>failed</literal> state and its exit code and status
 876             is recorded for introspection by the administrator until the
 877             service is restarted or reset with this command.</para>
 878           </listitem>
 879         </varlistentry>
 880
 881         <varlistentry>
 882           <term>
 883             <command>list-dependencies</command>
 884             <optional><replaceable>NAME</replaceable></optional>
 885           </term>
 886
 887           <listitem>
 888             <para>Shows units required and wanted by the specified
 889             unit. This recursively lists units following the
 890             <varname>Requires=</varname>,
 891             <varname>RequiresOverridable=</varname>,
 892             <varname>Requisite=</varname>,
 893             <varname>RequisiteOverridable=</varname>,
 894             <varname>Wants=</varname>, <varname>BindsTo=</varname>
 895             dependencies. If no unit is specified,
 896             <filename>default.target</filename> is implied.</para>
 897
 898             <para>By default, only target units are recursively
 899             expanded. When <option>--all</option> is passed, all other
 900             units are recursively expanded as well.</para>
 901
 902             <para>Options <option>--reverse</option>,
 903             <option>--after</option>, <option>--before</option>
 904             may be used to change what types of dependencies
 905             are shown.</para>
 906           </listitem>
 907         </varlistentry>
 908       </variablelist>
 909     </refsect2>
 910
 911     <refsect2>
 912       <title>Unit File Commands</title>
 913
 914       <variablelist>
 915         <varlistentry>
 916           <term><command>list-unit-files <optional><replaceable>PATTERN...</replaceable></optional></command></term>
 917
 918           <listitem>
 919             <para>List installed unit files. If one or more
 920             <replaceable>PATTERN</replaceable>s are specified, only
 921             units whose filename (just the last component of the path)
 922             matches one of them are shown.</para>
 923           </listitem>
 924         </varlistentry>
 925
 926         <varlistentry>
 927           <term><command>enable <replaceable>NAME</replaceable>...</command></term>
 928
 929           <listitem>
 930             <para>Enable one or more unit files or unit file instances,
 931             as specified on the command line. This will create a number
 932             of symlinks as encoded in the <literal>[Install]</literal>
 933             sections of the unit files. After the symlinks have been
 934             created, the systemd configuration is reloaded (in a way that
 935             is equivalent to <command>daemon-reload</command>) to ensure
 936             the changes are taken into account immediately. Note that
 937             this does <emphasis>not</emphasis> have the effect of also
 938             starting any of the units being enabled. If this
 939             is desired, either <option>--now</option> should be used
 940             together with this command, or an additional <command>start</command>
 941             command must be invoked for the unit. Also note that in case of
 942             instance enablement, symlinks named the same as instances
 943             are created in the install location, however they all point to the
 944             same template unit file.</para>
 945
 946             <para>This command will print the actions executed. This
 947             output may be suppressed by passing <option>--quiet</option>.
 948             </para>
 949
 950             <para>Note that this operation creates only the suggested
 951             symlinks for the units. While this command is the
 952             recommended way to manipulate the unit configuration
 953             directory, the administrator is free to make additional
 954             changes manually by placing or removing symlinks in the
 955             directory. This is particularly useful to create
 956             configurations that deviate from the suggested default
 957             installation. In this case, the administrator must make sure
 958             to invoke <command>daemon-reload</command> manually as
 959             necessary to ensure the changes are taken into account.
 960             </para>
 961
 962             <para>Enabling units should not be confused with starting
 963             (activating) units, as done by the <command>start</command>
 964             command. Enabling and starting units is orthogonal: units
 965             may be enabled without being started and started without
 966             being enabled. Enabling simply hooks the unit into various
 967             suggested places (for example, so that the unit is
 968             automatically started on boot or when a particular kind of
 969             hardware is plugged in). Starting actually spawns the daemon
 970             process (in case of service units), or binds the socket (in
 971             case of socket units), and so on.</para>
 972
 973             <para>Depending on whether <option>--system</option>,
 974             <option>--user</option>, <option>--runtime</option>,
 975             or <option>--global</option> is specified, this enables the unit
 976             for the system, for the calling user only, for only this boot of
 977             the system, or for all future logins of all users, or only this
 978             boot.  Note that in the last case, no systemd daemon
 979             configuration is reloaded.</para>
 980
 981             <para>Using <command>enable</command> on masked units
 982             results in an error.</para>
 983           </listitem>
 984         </varlistentry>
 985
 986         <varlistentry>
 987           <term><command>disable <replaceable>NAME</replaceable>...</command></term>
 988
 989           <listitem>
 990             <para>Disables one or more units. This removes all symlinks
 991             to the specified unit files from the unit configuration
 992             directory, and hence undoes the changes made by
 993             <command>enable</command>. Note however that this removes
 994             all symlinks to the unit files (i.e. including manual
 995             additions), not just those actually created by
 996             <command>enable</command>. This call implicitly reloads the
 997             systemd daemon configuration after completing the disabling
 998             of the units. Note that this command does not implicitly
 999             stop the units that are being disabled. If this is desired, either
1000             <option>--now</option> should be used together with this command, or
1001             an additional <command>stop</command> command should be executed
1002             afterwards.</para>
1003
1004             <para>This command will print the actions executed. This
1005             output may be suppressed by passing <option>--quiet</option>.
1006             </para>
1007
1008             <para>This command honors <option>--system</option>,
1009             <option>--user</option>, <option>--runtime</option> and
1010             <option>--global</option> in a similar way as
1011             <command>enable</command>.</para>
1012           </listitem>
1013         </varlistentry>
1014
1015         <varlistentry>
1016           <term><command>reenable <replaceable>NAME</replaceable>...</command></term>
1017
1018           <listitem>
1019             <para>Reenable one or more unit files, as specified on the
1020             command line. This is a combination of
1021             <command>disable</command> and <command>enable</command> and
1022             is useful to reset the symlinks a unit is enabled with to
1023             the defaults configured in the <literal>[Install]</literal>
1024             section of the unit file.</para>
1025           </listitem>
1026         </varlistentry>
1027
1028         <varlistentry>
1029           <term><command>preset <replaceable>NAME</replaceable>...</command></term>
1030
1031           <listitem>
1032             <para>Reset one or more unit files, as specified on the
1033             command line, to the defaults configured in the preset
1034             policy files. This has the same effect as
1035             <command>disable</command> or <command>enable</command>,
1036             depending how the unit is listed in the preset files.</para>
1037
1038             <para>Use <option>--preset-mode=</option> to control
1039             whether units shall be enabled and disabled, or only
1040             enabled, or only disabled.</para>
1041
1042             <para>For more information on the preset policy format,
1043             see
1044             <citerefentry><refentrytitle>systemd.preset</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
1045             For more information on the concept of presets, please
1046             consult the <ulink
1047             url="http://freedesktop.org/wiki/Software/systemd/Preset">Preset</ulink>
1048             document.</para>
1049           </listitem>
1050         </varlistentry>
1051
1052         <varlistentry>
1053           <term><command>preset-all</command></term>
1054
1055           <listitem>
1056             <para>Resets all installed unit files to the defaults
1057             configured in the preset policy file (see above).</para>
1058
1059             <para>Use <option>--preset-mode=</option> to control
1060             whether units shall be enabled and disabled, or only
1061             enabled, or only disabled.</para>
1062           </listitem>
1063         </varlistentry>
1064
1065         <varlistentry>
1066           <term><command>is-enabled <replaceable>NAME</replaceable>...</command></term>
1067
1068           <listitem>
1069             <para>Checks whether any of the specified unit files are
1070             enabled (as with <command>enable</command>). Returns an
1071             exit code of 0 if at least one is enabled, non-zero
1072             otherwise. Prints the current enable status (see table).
1073             To suppress this output, use <option>--quiet</option>.
1074             </para>
1075
1076             <table>
1077               <title>
1078                 <command>is-enabled</command> output
1079               </title>
1080
1081               <tgroup cols='3'>
1082                 <thead>
1083                   <row>
1084                     <entry>Printed string</entry>
1085                     <entry>Meaning</entry>
1086                     <entry>Return value</entry>
1087                   </row>
1088                 </thead>
1089                 <tbody>
1090                   <row>
1091                     <entry><literal>enabled</literal></entry>
1092                     <entry morerows='1'>Enabled through a symlink in <filename>.wants</filename> directory (permanently or just in <filename>/run</filename>).</entry>
1093                     <entry morerows='1'>0</entry>
1094                   </row>
1095                   <row>
1096                     <entry><literal>enabled-runtime</literal></entry>
1097                   </row>
1098                   <row>
1099                     <entry><literal>linked</literal></entry>
1100                     <entry morerows='1'>Made available through a symlink to the unit file (permanently or just in <filename>/run</filename>).</entry>
1101                     <entry morerows='1'>1</entry>
1102                   </row>
1103                   <row>
1104                     <entry><literal>linked-runtime</literal></entry>
1105                   </row>
1106                   <row>
1107                     <entry><literal>masked</literal></entry>
1108                     <entry morerows='1'>Disabled entirely (permanently or just in <filename>/run</filename>).</entry>
1109                     <entry morerows='1'>1</entry>
1110                   </row>
1111                   <row>
1112                     <entry><literal>masked-runtime</literal></entry>
1113                   </row>
1114                   <row>
1115                     <entry><literal>static</literal></entry>
1116                     <entry>Unit file is not enabled, and has no provisions for enabling in the <literal>[Install]</literal> section.</entry>
1117                     <entry>0</entry>
1118                   </row>
1119                   <row>
1120                     <entry><literal>indirect</literal></entry>
1121                     <entry>Unit file itself is not enabled, but it has a non-empty <varname>Also=</varname> setting in the <literal>[Install]</literal> section, listing other unit files that might be enabled.</entry>
1122                     <entry>0</entry>
1123                   </row>
1124                   <row>
1125                     <entry><literal>disabled</literal></entry>
1126                     <entry>Unit file is not enabled.</entry>
1127                     <entry>1</entry>
1128                   </row>
1129                 </tbody>
1130               </tgroup>
1131             </table>
1132
1133           </listitem>
1134         </varlistentry>
1135
1136         <varlistentry>
1137           <term><command>mask <replaceable>NAME</replaceable>...</command></term>
1138
1139           <listitem>
1140             <para>Mask one or more unit files, as specified on the
1141             command line. This will link these units to
1142             <filename>/dev/null</filename>, making it impossible to
1143             start them. This is a stronger version of
1144             <command>disable</command>, since it prohibits all kinds of
1145             activation of the unit, including enablement and manual
1146             activation. Use this option with care. This honors the
1147             <option>--runtime</option> option to only mask temporarily
1148             until the next reboot of the system. The <option>--now</option>
1149             option can be used to ensure that the units are also stopped.</para>
1150           </listitem>
1151         </varlistentry>
1152
1153         <varlistentry>
1154           <term><command>unmask <replaceable>NAME</replaceable>...</command></term>
1155
1156           <listitem>
1157             <para>Unmask one or more unit files, as specified on the
1158             command line. This will undo the effect of
1159             <command>mask</command>.</para>
1160           </listitem>
1161         </varlistentry>
1162
1163         <varlistentry>
1164           <term><command>link <replaceable>FILENAME</replaceable>...</command></term>
1165
1166           <listitem>
1167             <para>Link a unit file that is not in the unit file search
1168             paths into the unit file search path. This requires an
1169             absolute path to a unit file. The effect of this can be
1170             undone with <command>disable</command>. The effect of this
1171             command is that a unit file is available for
1172             <command>start</command> and other commands although it
1173             is not installed directly in the unit search path.</para>
1174           </listitem>
1175         </varlistentry>
1176
1177         <varlistentry>
1178           <term><command>add-wants <replaceable>TARGET</replaceable>
1179           <replaceable>NAME</replaceable>...</command></term>
1180           <term><command>add-requires <replaceable>TARGET</replaceable>
1181           <replaceable>NAME</replaceable>...</command></term>
1182
1183           <listitem>
1184             <para>Adds <literal>Wants=</literal> or <literal>Requires=</literal>
1185             dependency, respectively, to the specified
1186             <replaceable>TARGET</replaceable> for one or more units. </para>
1187
1188             <para>This command honors <option>--system</option>,
1189             <option>--user</option>, <option>--runtime</option> and
1190             <option>--global</option> in a similar way as
1191             <command>enable</command>.</para>
1192
1193           </listitem>
1194         </varlistentry>
1195
1196         <varlistentry>
1197           <term><command>edit <replaceable>NAME</replaceable>...</command></term>
1198
1199           <listitem>
1200             <para>Edit a drop-in snippet or a whole replacement file if
1201             <option>--full</option> is specified, to extend or override the
1202             specified unit.</para>
1203
1204             <para>Depending on whether <option>--system</option> (the default),
1205             <option>--user</option>, or <option>--global</option> is specified,
1206             this creates a drop-in file for each unit either for the system,
1207             for the calling user or for all futures logins of all users. Then,
1208             the editor (see the "Environment" section below) is invoked on
1209             temporary files which will be written to the real location if the
1210             editor exits successfully.</para>
1211
1212             <para>If <option>--full</option> is specified, this will copy the
1213             original units instead of creating drop-in files.</para>
1214
1215             <para>If <option>--runtime</option> is specified, the changes will
1216             be made temporarily in <filename>/run</filename> and they will be
1217             lost on the next reboot.</para>
1218
1219             <para>If the temporary file is empty upon exit the modification of
1220             the related unit is canceled</para>
1221
1222             <para>After the units have been edited, systemd configuration is
1223             reloaded (in a way that is equivalent to <command>daemon-reload</command>).
1224             </para>
1225
1226             <para>Note that this command cannot be used to remotely edit units
1227             and that you cannot temporarily edit units which are in
1228             <filename>/etc</filename> since they take precedence over
1229             <filename>/run</filename>.</para>
1230           </listitem>
1231         </varlistentry>
1232
1233         <varlistentry>
1234           <term><command>get-default</command></term>
1235
1236           <listitem>
1237             <para>Return the default target to boot into. This returns
1238             the target unit name <filename>default.target</filename>
1239             is aliased (symlinked) to.</para>
1240           </listitem>
1241         </varlistentry>
1242
1243         <varlistentry>
1244           <term><command>set-default <replaceable>NAME</replaceable></command></term>
1245
1246           <listitem>
1247             <para>Set the default target to boot into. This sets
1248             (symlinks) the <filename>default.target</filename> alias
1249             to the given target unit.</para>
1250           </listitem>
1251         </varlistentry>
1252
1253       </variablelist>
1254     </refsect2>
1255
1256     <refsect2>
1257       <title>Machine Commands</title>
1258
1259       <variablelist>
1260         <varlistentry>
1261           <term><command>list-machines <optional><replaceable>PATTERN</replaceable>...</optional></command></term>
1262
1263           <listitem>
1264             <para>List the host and all running local containers with
1265             their state. If one or more
1266             <replaceable>PATTERN</replaceable>s are specified, only
1267             containers matching one of them are shown.
1268             </para>
1269           </listitem>
1270         </varlistentry>
1271       </variablelist>
1272     </refsect2>
1273
1274     <refsect2>
1275       <title>Job Commands</title>
1276
1277       <variablelist>
1278         <varlistentry>
1279           <term><command>list-jobs <optional><replaceable>PATTERN...</replaceable></optional></command></term>
1280
1281           <listitem>
1282             <para>List jobs that are in progress. If one or more
1283             <replaceable>PATTERN</replaceable>s are specified, only
1284             jobs for units matching one of them are shown.</para>
1285           </listitem>
1286         </varlistentry>
1287         <varlistentry>
1288           <term><command>cancel <replaceable>JOB</replaceable>...</command></term>
1289
1290           <listitem>
1291             <para>Cancel one or more jobs specified on the command line
1292             by their numeric job IDs. If no job ID is specified, cancel
1293             all pending jobs.</para>
1294           </listitem>
1295         </varlistentry>
1296       </variablelist>
1297     </refsect2>
1298
1299     <refsect2>
1300       <title>Snapshot Commands</title>
1301
1302       <variablelist>
1303         <varlistentry>
1304           <term><command>snapshot <optional><replaceable>NAME</replaceable></optional></command></term>
1305
1306           <listitem>
1307             <para>Create a snapshot. If a snapshot name is specified,
1308             the new snapshot will be named after it. If none is
1309             specified, an automatic snapshot name is generated. In
1310             either case, the snapshot name used is printed to standard
1311             output, unless <option>--quiet</option> is specified.
1312             </para>
1313
1314             <para>A snapshot refers to a saved state of the systemd
1315             manager. It is implemented itself as a unit that is
1316             generated dynamically with this command and has dependencies
1317             on all units active at the time. At a later time, the user
1318             may return to this state by using the
1319             <command>isolate</command> command on the snapshot unit.
1320             </para>
1321
1322             <para>Snapshots are only useful for saving and restoring
1323             which units are running or are stopped, they do not
1324             save/restore any other state. Snapshots are dynamic and lost
1325             on reboot.</para>
1326           </listitem>
1327         </varlistentry>
1328         <varlistentry>
1329           <term><command>delete <replaceable>PATTERN</replaceable>...</command></term>
1330
1331           <listitem>
1332             <para>Remove a snapshot previously created with
1333             <command>snapshot</command>.</para>
1334           </listitem>
1335         </varlistentry>
1336       </variablelist>
1337     </refsect2>
1338
1339     <refsect2>
1340       <title>Environment Commands</title>
1341
1342       <variablelist>
1343         <varlistentry>
1344           <term><command>show-environment</command></term>
1345
1346           <listitem>
1347             <para>Dump the systemd manager environment block. The
1348             environment block will be dumped in straight-forward form
1349             suitable for sourcing into a shell script. This environment
1350             block will be passed to all processes the manager
1351             spawns.</para>
1352           </listitem>
1353         </varlistentry>
1354         <varlistentry>
1355           <term><command>set-environment <replaceable>VARIABLE=VALUE</replaceable>...</command></term>
1356
1357           <listitem>
1358             <para>Set one or more systemd manager environment variables,
1359             as specified on the command line.</para>
1360           </listitem>
1361         </varlistentry>
1362         <varlistentry>
1363           <term><command>unset-environment <replaceable>VARIABLE</replaceable>...</command></term>
1364
1365           <listitem>
1366             <para>Unset one or more systemd manager environment
1367             variables. If only a variable name is specified, it will be
1368             removed regardless of its value. If a variable and a value
1369             are specified, the variable is only removed if it has the
1370             specified value.</para>
1371           </listitem>
1372         </varlistentry>
1373         <varlistentry>
1374           <term>
1375             <command>import-environment</command>
1376             <optional><replaceable>VARIABLE...</replaceable></optional>
1377           </term>
1378
1379           <listitem>
1380             <para>Import all, one or more environment variables set on
1381             the client into the systemd manager environment block. If
1382             no arguments are passed, the entire environment block is
1383             imported. Otherwise, a list of one or more environment
1384             variable names should be passed, whose client-side values
1385             are then imported into the manager's environment
1386             block.</para>
1387           </listitem>
1388         </varlistentry>
1389       </variablelist>
1390     </refsect2>
1391
1392     <refsect2>
1393       <title>Manager Lifecycle Commands</title>
1394
1395       <variablelist>
1396         <varlistentry>
1397           <term><command>daemon-reload</command></term>
1398
1399           <listitem>
1400             <para>Reload systemd manager configuration. This will
1401             rerun all generators (see
1402             <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>),
1403             reload all unit files, and recreate the entire dependency
1404             tree. While the daemon is being reloaded, all sockets
1405             systemd listens on behalf of user configuration will stay
1406             accessible.</para>
1407
1408             <para>This command should not be confused with the
1409             <command>reload</command> command.</para>
1410           </listitem>
1411         </varlistentry>
1412         <varlistentry>
1413           <term><command>daemon-reexec</command></term>
1414
1415           <listitem>
1416             <para>Reexecute the systemd manager. This will serialize the
1417             manager state, reexecute the process and deserialize the
1418             state again. This command is of little use except for
1419             debugging and package upgrades. Sometimes, it might be
1420             helpful as a heavy-weight <command>daemon-reload</command>.
1421             While the daemon is being reexecuted, all sockets systemd listening
1422             on behalf of user configuration will stay accessible.
1423             </para>
1424           </listitem>
1425         </varlistentry>
1426       </variablelist>
1427     </refsect2>
1428
1429     <refsect2>
1430       <title>System Commands</title>
1431
1432       <variablelist>
1433         <varlistentry>
1434           <term><command>is-system-running</command></term>
1435
1436           <listitem>
1437             <para>Checks whether the system is operational. This
1438             returns success when the system is fully up and running,
1439             meaning not in startup, shutdown or maintenance
1440             mode. Failure is returned otherwise. In addition, the
1441             current state is printed in a short string to standard
1442             output, see table below. Use <option>--quiet</option> to
1443             suppress this output.</para>
1444
1445             <table>
1446               <title>Manager Operational States</title>
1447               <tgroup cols='2'>
1448                 <colspec colname='name' />
1449                 <colspec colname='description' />
1450                 <thead>
1451                   <row>
1452                     <entry>Name</entry>
1453                     <entry>Description</entry>
1454                   </row>
1455                 </thead>
1456                 <tbody>
1457                   <row>
1458                     <entry><varname>initializing</varname></entry>
1459                     <entry><para>Early bootup, before
1460                     <filename>basic.target</filename> is reached
1461                     or the <varname>maintenance</varname> state entered.
1462                     </para></entry>
1463                   </row>
1464                   <row>
1465                     <entry><varname>starting</varname></entry>
1466                     <entry><para>Late bootup, before the job queue
1467                     becomes idle for the first time, or one of the
1468                     rescue targets are reached.</para></entry>
1469                   </row>
1470                   <row>
1471                     <entry><varname>running</varname></entry>
1472                     <entry><para>The system is fully
1473                     operational.</para></entry>
1474                   </row>
1475                   <row>
1476                     <entry><varname>degraded</varname></entry>
1477                     <entry><para>The system is operational but one or more
1478                     units failed.</para></entry>
1479                   </row>
1480                   <row>
1481                     <entry><varname>maintenance</varname></entry>
1482                     <entry><para>The rescue or emergency target is
1483                     active.</para></entry>
1484                   </row>
1485                   <row>
1486                     <entry><varname>stopping</varname></entry>
1487                     <entry><para>The manager is shutting
1488                     down.</para></entry>
1489                   </row>
1490                 </tbody>
1491               </tgroup>
1492             </table>
1493           </listitem>
1494         </varlistentry>
1495
1496         <varlistentry>
1497           <term><command>default</command></term>
1498
1499           <listitem>
1500             <para>Enter default mode. This is mostly equivalent to
1501             <command>isolate default.target</command>.</para>
1502           </listitem>
1503         </varlistentry>
1504
1505         <varlistentry>
1506           <term><command>rescue</command></term>
1507
1508           <listitem>
1509             <para>Enter rescue mode. This is mostly equivalent to
1510             <command>isolate rescue.target</command>, but also prints a
1511             wall message to all users.</para>
1512           </listitem>
1513         </varlistentry>
1514         <varlistentry>
1515           <term><command>emergency</command></term>
1516
1517           <listitem>
1518             <para>Enter emergency mode. This is mostly equivalent to
1519             <command>isolate emergency.target</command>, but also prints
1520             a wall message to all users.</para>
1521           </listitem>
1522         </varlistentry>
1523         <varlistentry>
1524           <term><command>halt</command></term>
1525
1526           <listitem>
1527             <para>Shut down and halt the system. This is mostly equivalent to
1528             <command>start halt.target --job-mode=replace-irreversibly</command>, but also
1529             prints a wall message to all users.  If combined with
1530             <option>--force</option>, shutdown of all running services is
1531             skipped, however all processes are killed and all file
1532             systems are unmounted or mounted read-only, immediately
1533             followed by the system halt.  If <option>--force</option> is
1534             specified twice, the operation is immediately executed
1535             without terminating any processes or unmounting any file
1536             systems. This may result in data loss.</para>
1537           </listitem>
1538         </varlistentry>
1539         <varlistentry>
1540           <term><command>poweroff</command></term>
1541
1542           <listitem>
1543             <para>Shut down and power-off the system. This is mostly
1544             equivalent to <command>start poweroff.target --job-mode=replace-irreversibly</command>,
1545             but also prints a wall message to all users. If combined with
1546             <option>--force</option>, shutdown of all running services is
1547             skipped, however all processes are killed and all file
1548             systems are unmounted or mounted read-only, immediately
1549             followed by the powering off. If <option>--force</option> is
1550             specified twice, the operation is immediately executed
1551             without terminating any processes or unmounting any file
1552             systems. This may result in data loss.</para>
1553           </listitem>
1554         </varlistentry>
1555         <varlistentry>
1556           <term><command>reboot <optional><replaceable>arg</replaceable></optional></command></term>
1557
1558           <listitem>
1559             <para>Shut down and reboot the system. This is mostly
1560             equivalent to <command>start reboot.target --job-mode=replace-irreversibly</command>,
1561             but also prints a wall message to all users. If combined with
1562             <option>--force</option>, shutdown of all running services is
1563             skipped, however all processes are killed and all file
1564             systems are unmounted or mounted read-only, immediately
1565             followed by the reboot. If <option>--force</option> is
1566             specified twice, the operation is immediately executed
1567             without terminating any processes or unmounting any file
1568             systems. This may result in data loss.</para>
1569
1570             <para>If the optional argument
1571             <replaceable>arg</replaceable> is given, it will be passed
1572             as the optional argument to the
1573             <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1574             system call. The value is architecture and firmware
1575             specific. As an example, <literal>recovery</literal> might
1576             be used to trigger system recovery, and
1577             <literal>fota</literal> might be used to trigger a
1578             <quote>firmware over the air</quote> update.</para>
1579           </listitem>
1580         </varlistentry>
1581
1582         <varlistentry>
1583           <term><command>kexec</command></term>
1584
1585           <listitem>
1586             <para>Shut down and reboot the system via kexec. This is
1587             mostly equivalent to <command>start kexec.target --job-mode=replace-irreversibly</command>,
1588             but also prints a wall message to all users. If combined
1589             with <option>--force</option>, shutdown of all running
1590             services is skipped, however all processes are killed and
1591             all file systems are unmounted or mounted read-only,
1592             immediately followed by the reboot.</para>
1593           </listitem>
1594         </varlistentry>
1595
1596         <varlistentry>
1597           <term><command>exit</command></term>
1598
1599           <listitem>
1600             <para>Ask the systemd manager to quit. This is only
1601             supported for user service managers (i.e. in conjunction
1602             with the <option>--user</option> option) and will fail
1603             otherwise.</para>
1604           </listitem>
1605         </varlistentry>
1606
1607         <varlistentry>
1608           <term><command>switch-root <replaceable>ROOT</replaceable> <optional><replaceable>INIT</replaceable></optional></command></term>
1609
1610           <listitem>
1611             <para>Switches to a different root directory and executes a
1612             new system manager process below it. This is intended for
1613             usage in initial RAM disks ("initrd"), and will transition
1614             from the initrd's system manager process (a.k.a "init"
1615             process) to the main system manager process. This call takes two
1616             arguments: the directory that is to become the new root directory, and
1617             the path to the new system manager binary below it to
1618             execute as PID 1. If the latter is omitted or the empty
1619             string, a systemd binary will automatically be searched for
1620             and used as init. If the system manager path is omitted or
1621             equal to the empty string, the state of the initrd's system
1622             manager process is passed to the main system manager, which
1623             allows later introspection of the state of the services
1624             involved in the initrd boot.</para>
1625           </listitem>
1626         </varlistentry>
1627
1628         <varlistentry>
1629           <term><command>suspend</command></term>
1630
1631           <listitem>
1632             <para>Suspend the system. This will trigger activation of
1633             the special <filename>suspend.target</filename> target.
1634             </para>
1635           </listitem>
1636         </varlistentry>
1637
1638         <varlistentry>
1639           <term><command>hibernate</command></term>
1640
1641           <listitem>
1642             <para>Hibernate the system. This will trigger activation of
1643             the special <filename>hibernate.target</filename> target.
1644             </para>
1645           </listitem>
1646         </varlistentry>
1647
1648         <varlistentry>
1649           <term><command>hybrid-sleep</command></term>
1650
1651           <listitem>
1652             <para>Hibernate and suspend the system. This will trigger
1653             activation of the special
1654             <filename>hybrid-sleep.target</filename> target.</para>
1655           </listitem>
1656         </varlistentry>
1657       </variablelist>
1658     </refsect2>
1659
1660     <refsect2>
1661       <title>Parameter Syntax</title>
1662
1663       <para>Unit commands listed above take either a single unit name
1664       (designated as <replaceable>NAME</replaceable>), or multiple
1665       unit specifications (designated as
1666       <replaceable>PATTERN</replaceable>...). In the first case, the
1667       unit name with or without a suffix must be given. If the suffix
1668       is not specified, systemctl will append a suitable suffix,
1669       <literal>.service</literal> by default, and a type-specific
1670       suffix in case of commands which operate only on specific unit
1671       types. For example,
1672       <programlisting># systemctl start sshd</programlisting> and
1673       <programlisting># systemctl start sshd.service</programlisting>
1674       are equivalent, as are
1675       <programlisting># systemctl isolate default</programlisting>
1676       and
1677       <programlisting># systemctl isolate default.target</programlisting>
1678       Note that (absolute) paths to device nodes are automatically
1679       converted to device unit names, and other (absolute) paths to
1680       mount unit names.
1681       <programlisting># systemctl status /dev/sda
1682 # systemctl status /home</programlisting>
1683       are equivalent to:
1684       <programlisting># systemctl status dev-sda.device
1685 # systemctl status home.mount</programlisting>
1686       In the second case, shell-style globs will be matched against
1687       currently loaded units; literal unit names, with or without
1688       a suffix, will be treated as in the first case. This means that
1689       literal unit names always refer to exactly one unit, but globs
1690       may match zero units and this is not considered an error.</para>
1691
1692       <para>Glob patterns use
1693       <citerefentry project='man-pages'><refentrytitle>fnmatch</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
1694       so normal shell-style globbing rules are used, and
1695       <literal>*</literal>, <literal>?</literal>,
1696       <literal>[]</literal> may be used. See
1697       <citerefentry project='man-pages'><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1698       for more details. The patterns are matched against the names of
1699       currently loaded units, and patterns which do not match anything
1700       are silently skipped. For example:
1701       <programlisting># systemctl stop sshd@*.service</programlisting>
1702       will stop all <filename>sshd@.service</filename> instances.
1703       </para>
1704
1705       <para>For unit file commands, the specified
1706       <replaceable>NAME</replaceable> should be the full name of the
1707       unit file, or the absolute path to the unit file:
1708       <programlisting># systemctl enable foo.service</programlisting>
1709       or
1710       <programlisting># systemctl link /path/to/foo.service</programlisting>
1711       </para>
1712     </refsect2>
1713
1714   </refsect1>
1715
1716   <refsect1>
1717     <title>Exit status</title>
1718
1719     <para>On success, 0 is returned, a non-zero failure
1720     code otherwise.</para>
1721   </refsect1>
1722
1723   <refsect1>
1724     <title>Environment</title>
1725
1726     <variablelist class='environment-variables'>
1727       <varlistentry>
1728         <term><varname>$SYSTEMD_EDITOR</varname></term>
1729
1730         <listitem><para>Editor to use when editing units; overrides
1731         <varname>$EDITOR</varname> and <varname>$VISUAL</varname>. If neither
1732         <varname>$SYSTEMD_EDITOR</varname> nor <varname>$EDITOR</varname> nor
1733         <varname>$VISUAL</varname> are present or if it is set to an empty
1734         string or if their execution failed, systemctl will try to execute well
1735         known editors in this order:
1736         <citerefentry project='die-net'><refentrytitle>editor</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1737         <citerefentry project='die-net'><refentrytitle>nano</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1738         <citerefentry project='die-net'><refentrytitle>vim</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1739         <citerefentry project='die-net'><refentrytitle>vi</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
1740         </para></listitem>
1741       </varlistentry>
1742     </variablelist>
1743     <xi:include href="less-variables.xml" xpointer="pager"/>
1744     <xi:include href="less-variables.xml" xpointer="less"/>
1745   </refsect1>
1746
1747   <refsect1>
1748     <title>See Also</title>
1749     <para>
1750       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1751       <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1752       <citerefentry><refentrytitle>loginctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1753       <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1754       <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1755       <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1756       <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1757       <citerefentry project='man-pages'><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1758       <citerefentry><refentrytitle>systemd.preset</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1759       <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
1760       <citerefentry project='man-pages'><refentrytitle>glob</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1761     </para>
1762   </refsect1>
1763
1764 </refentry>