man/systemctl.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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   6   This file is part of systemd.
   7
   8   Copyright 2010 Lennart Poettering
   9
  10   systemd is free software; you can redistribute it and/or modify it
  11   under the terms of the GNU General Public License as published by
  12   the Free Software Foundation; either version 2 of the License, or
  13   (at your option) any later version.
  14
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  18   General Public License for more details.
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  20   You should have received a copy of the GNU General Public License
  21   along with systemd; If not, see <http://www.gnu.org/licenses/>.
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  23
  24 <refentry id="systemctl">
  25
  26         <refentryinfo>
  27                 <title>systemctl</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>systemctl</refentrytitle>
  42                 <manvolnum>1</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemctl</refname>
  47                 <refpurpose>Control the systemd system and service manager</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <cmdsynopsis>
  52                         <command>systemctl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg> <arg choice="opt" rep="repeat">NAME</arg></command>
  53                 </cmdsynopsis>
  54         </refsynopsisdiv>
  55
  56         <refsect1>
  57                 <title>Description</title>
  58
  59                 <para><command>systemctl</command> may be used to
  60                 introspect and control the state of the
  61                 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
  62                 system and service manager.</para>
  63         </refsect1>
  64
  65         <refsect1>
  66                 <title>Options</title>
  67
  68                 <para>The following options are understood:</para>
  69
  70                 <variablelist>
  71                         <varlistentry>
  72                                 <term><option>--help</option></term>
  73                                 <term><option>-h</option></term>
  74
  75                                 <listitem><para>Prints a short help
  76                                 text and exits.</para></listitem>
  77                         </varlistentry>
  78
  79                         <varlistentry>
  80                                 <term><option>--version</option></term>
  81
  82                                 <listitem><para>Prints a short version
  83                                 string and exits.</para></listitem>
  84                         </varlistentry>
  85
  86                         <varlistentry>
  87                                 <term><option>--type=</option></term>
  88                                 <term><option>-t</option></term>
  89
  90                                 <listitem><para>When listing units,
  91                                 limit display to certain unit
  92                                 types. If not specified units of all
  93                                 types will be shown. The argument
  94                                 should be a unit type name such as
  95                                 <option>service</option>,
  96                                 <option>socket</option> and
  97                                 similar.</para></listitem>
  98                         </varlistentry>
  99
 100                         <varlistentry>
 101                                 <term><option>--property=</option></term>
 102                                 <term><option>-p</option></term>
 103
 104                                 <listitem><para>When showing
 105                                 unit/job/manager information, limit
 106                                 display to certain properties as
 107                                 specified as argument. If not
 108                                 specified all set properties are
 109                                 shown. The argument should be a
 110                                 property name, such as
 111                                 <literal>MainPID</literal>. If
 112                                 specified more than once all
 113                                 properties with the specified names
 114                                 are shown.</para></listitem>
 115                         </varlistentry>
 116
 117                         <varlistentry>
 118                                 <term><option>--all</option></term>
 119                                 <term><option>-a</option></term>
 120
 121                                 <listitem><para>When listing units,
 122                                 show all units, regardless of their
 123                                 state, including inactive units. When
 124                                 showing unit/job/manager information,
 125                                 show all properties regardless whether
 126                                 they are set or not.</para></listitem>
 127                         </varlistentry>
 128
 129                         <varlistentry>
 130                                 <term><option>--failed</option></term>
 131
 132                                 <listitem><para>When listing units,
 133                                 show only failed units. Do not confuse
 134                                 with
 135                                 <option>--fail</option>.</para></listitem>
 136                         </varlistentry>
 137
 138                         <varlistentry>
 139                                 <term><option>--full</option></term>
 140
 141                                 <listitem><para>Do not ellipsize unit
 142                                 names and truncate unit descriptions
 143                                 in the output of
 144                                 <command>list-units</command> and
 145                                 <command>list-jobs</command>.</para></listitem>
 146                         </varlistentry>
 147
 148                         <varlistentry>
 149                                 <term><option>--fail</option></term>
 150
 151                                 <listitem><para>If the requested
 152                                 operation conflicts with a pending
 153                                 unfinished job, fail the command. If
 154                                 this is not specified the requested
 155                                 operation will replace the pending job,
 156                                 if necessary. Do not confuse
 157                                 with
 158                                 <option>--failed</option>.</para></listitem>
 159                         </varlistentry>
 160
 161                         <varlistentry>
 162                                 <term><option>--quiet</option></term>
 163                                 <term><option>-q</option></term>
 164
 165                                 <listitem><para>Suppress output to
 166                                 STDOUT in
 167                                 <command>snapshot</command>,
 168                                 <command>is-active</command>,
 169                                 <command>enable</command> and
 170                                 <command>disable</command>.</para></listitem>
 171                         </varlistentry>
 172
 173                         <varlistentry>
 174                                 <term><option>--no-block</option></term>
 175
 176                                 <listitem><para>Do not synchronously wait for
 177                                 the requested operation to finish. If this is
 178                                 not specified the job will be verified,
 179                                 enqueued and <command>systemctl</command> will
 180                                 wait until it is completed. By passing this
 181                                 argument it is only verified and
 182                                 enqueued.</para></listitem> </varlistentry>
 183
 184                         <varlistentry>
 185                                 <term><option>--no-pager</option></term>
 186
 187                                 <listitem><para>Do not pipe output into a
 188                                 pager.</para></listitem>
 189                         </varlistentry>
 190
 191                         <varlistentry>
 192                                 <term><option>--system</option></term>
 193
 194                                 <listitem><para>Talk to the systemd
 195                                 system manager. (Default)</para></listitem>
 196                         </varlistentry>
 197
 198                         <varlistentry>
 199                                 <term><option>--user</option></term>
 200
 201                                 <listitem><para>Talk to the systemd
 202                                 manager of the calling user.</para></listitem>
 203                         </varlistentry>
 204
 205                         <varlistentry>
 206                                 <term><option>--order</option></term>
 207                                 <term><option>--require</option></term>
 208
 209                                 <listitem><para>When used in
 210                                 conjunction with the
 211                                 <command>dot</command> command (see
 212                                 below), selects which dependencies are
 213                                 shown in the dependency graph. If
 214                                 <option>--order</option> is passed
 215                                 only dependencies of type
 216                                 <varname>After=</varname> or
 217                                 <varname>Before=</varname> are
 218                                 shown. If <option>--require</option>
 219                                 is passed only dependencies of type
 220                                 <varname>Requires=</varname>,
 221                                 <varname>RequiresOverridable=</varname>,
 222                                 <varname>Requisite=</varname>,
 223                                 <varname>RequisiteOverridable=</varname>,
 224                                 <varname>Wants=</varname> and
 225                                 <varname>Conflicts=</varname> are
 226                                 shown. If neither is passed, shows
 227                                 dependencies of all these
 228                                 types.</para></listitem>
 229                         </varlistentry>
 230
 231                         <varlistentry>
 232                                 <term><option>--no-wall</option></term>
 233
 234                                 <listitem><para>Don't send wall
 235                                 message before
 236                                 halt, power-off, reboot.</para></listitem>
 237                         </varlistentry>
 238
 239                         <varlistentry>
 240                                 <term><option>--global</option></term>
 241
 242                                 <listitem><para>When used with
 243                                 <command>enable</command> and
 244                                 <command>disable</command>, operate on the
 245                                 global user configuration
 246                                 directory, thus enabling or disabling
 247                                 a unit file globally for all future
 248                                 logins of all users.</para></listitem>
 249                         </varlistentry>
 250
 251                         <varlistentry>
 252                                 <term><option>--no-reload</option></term>
 253
 254                                 <listitem><para>When used with
 255                                 <command>enable</command> and
 256                                 <command>disable</command>, do not
 257                                 implicitly reload daemon configuration
 258                                 after executing the
 259                                 changes.</para></listitem>
 260                         </varlistentry>
 261
 262                         <varlistentry>
 263                                 <term><option>--no-ask-password</option></term>
 264
 265                                 <listitem><para>When used with
 266                                 <command>start</command> and related
 267                                 commands, disables asking for
 268                                 passwords. Background services may
 269                                 require input of a password or
 270                                 passphrase string, for example to
 271                                 unlock system hard disks or
 272                                 cryptographic certificates. Unless
 273                                 this option is specified and the
 274                                 command is invoked from a terminal
 275                                 <command>systemctl</command> will
 276                                 query the user on the terminal for the
 277                                 necessary secrets. Use this option to
 278                                 switch this behavior off. In this
 279                                 case the password must be supplied by
 280                                 some other means (for example
 281                                 graphical password agents) or the
 282                                 service might fail.</para></listitem>
 283                         </varlistentry>
 284
 285                         <varlistentry>
 286                                 <term><option>--kill-mode=</option></term>
 287
 288                                 <listitem><para>When used with
 289                                 <command>kill</command>, choose the
 290                                 mode how to kill the selected
 291                                 processes. Must be one of
 292                                 <option>control-group</option>,
 293                                 <option>process-group</option> or
 294                                 <option>process</option> to select
 295                                 whether to kill the entire control
 296                                 group, the process group or only the
 297                                 selected process itself. If omitted
 298                                 defaults to
 299                                 <option>control-group</option> if
 300                                 <option>--kill-who=all</option> is
 301                                 set, or <option>process</option>
 302                                 otherwise. You probably never need to
 303                                 use this switch.</para></listitem>
 304                         </varlistentry>
 305
 306                         <varlistentry>
 307                                 <term><option>--kill-who=</option></term>
 308
 309                                 <listitem><para>When used with
 310                                 <command>kill</command>, choose which
 311                                 processes to kill. Must be one of
 312                                 <option>main</option>,
 313                                 <option>control</option> or
 314                                 <option>all</option> to select whether
 315                                 to kill only the main process of the
 316                                 unit, the control process or all
 317                                 processes of the unit. If omitted
 318                                 defaults to
 319                                 <option>all</option>.</para></listitem>
 320                         </varlistentry>
 321
 322                         <varlistentry>
 323                                 <term><option>--signal=</option></term>
 324                                 <term><option>-s</option></term>
 325
 326                                 <listitem><para>When used with
 327                                 <command>kill</command>, choose which
 328                                 signal to send to selected
 329                                 processes. Must be one of the well
 330                                 known signal specifiers such as
 331                                 SIGTERM, SIGINT or SIGSTOP. If
 332                                 omitted defaults to
 333                                 <option>SIGTERM</option>.</para></listitem>
 334                         </varlistentry>
 335
 336                         <varlistentry>
 337                                 <term><option>--force</option></term>
 338                                 <term><option>-f</option></term>
 339
 340                                 <listitem><para>When used with
 341                                 <command>enable</command>, override any
 342                                 existing conflicting
 343                                 symlinks.</para></listitem>
 344
 345                                 <listitem><para>When used with
 346                                 <command>halt</command>,
 347                                 <command>poweroff</command>,
 348                                 <command>reboot</command> or
 349                                 <command>kexec</command> execute
 350                                 selected operation without shutting
 351                                 down all units. However, all processes
 352                                 will be killed forcibly and all file
 353                                 systems are unmounted or remounted
 354                                 read-only. This is hence a drastic but
 355                                 relatively safe option to request an
 356                                 immediate reboot.</para></listitem>
 357                         </varlistentry>
 358
 359                         <varlistentry>
 360                                 <term><option>--defaults</option></term>
 361
 362                                 <listitem><para>When used with
 363                                 <command>disable</command>, ensures
 364                                 that only the symlinks created by
 365                                 <command>enable</command> are removed,
 366                                 not all symlinks pointing to the unit
 367                                 file that shall be
 368                                 disabled.</para></listitem>
 369                         </varlistentry>
 370                 </variablelist>
 371
 372                 <para>The following commands are understood:</para>
 373
 374                 <variablelist>
 375                         <varlistentry>
 376                                 <term><command>list-units</command></term>
 377
 378                                 <listitem><para>List known units.</para></listitem>
 379                         </varlistentry>
 380                         <varlistentry>
 381                                 <term><command>start [NAME...]</command></term>
 382
 383                                 <listitem><para>Start (activate) one
 384                                 or more units specified on the command
 385                                 line.</para></listitem>
 386                         </varlistentry>
 387                         <varlistentry>
 388                                 <term><command>stop [NAME...]</command></term>
 389
 390                                 <listitem><para>Stop (deactivate) one
 391                                 or more units specified on the command
 392                                 line.</para></listitem>
 393                         </varlistentry>
 394                         <varlistentry>
 395                                 <term><command>reload [NAME...]</command></term>
 396
 397                                 <listitem><para>Asks all units listed
 398                                 on the command line to reload their
 399                                 configuration. Note that this will
 400                                 reload the service-specific
 401                                 configuration, not the unit
 402                                 configuration file of systemd. If you
 403                                 want systemd to reload the
 404                                 configuration file of a unit use the
 405                                 <command>daemon-reload</command>
 406                                 command. In other words: for the
 407                                 example case of Apache, this will
 408                                 reload Apache's
 409                                 <filename>httpd.conf</filename> in the
 410                                 web server, not the
 411                                 <filename>apache.service</filename>
 412                                 systemd unit file. </para>
 413
 414                                 <para>This command should not be
 415                                 confused with the
 416                                 <command>daemon-reload</command> or
 417                                 <command>load</command>
 418                                 commands.</para></listitem>
 419
 420                         </varlistentry>
 421                         <varlistentry>
 422                                 <term><command>restart [NAME...]</command></term>
 423
 424                                 <listitem><para>Restart one or more
 425                                 units specified on the command
 426                                 line. If the units are not running yet
 427                                 they will be
 428                                 started.</para></listitem>
 429                         </varlistentry>
 430                         <varlistentry>
 431                                 <term><command>try-restart [NAME...]</command></term>
 432
 433                                 <listitem><para>Restart one or more
 434                                 units specified on the command
 435                                 line. If the units are not running yet
 436                                 the operation will
 437                                 fail. Note that for compatibility
 438                                 with Red Hat init scripts
 439                                 <command>condrestart</command> is
 440                                 equivalent to this command.</para></listitem>
 441                         </varlistentry>
 442                         <varlistentry>
 443                                 <term><command>reload-or-restart [NAME...]</command></term>
 444
 445                                 <listitem><para>Reload one or more
 446                                 units if they support it. If not,
 447                                 restart them instead. If the units
 448                                 are not running yet they will be
 449                                 started.</para></listitem>
 450                         </varlistentry>
 451                         <varlistentry>
 452                                 <term><command>reload-or-try-restart [NAME...]</command></term>
 453
 454                                 <listitem><para>Reload one or more
 455                                 units if they support it. If not,
 456                                 restart them instead. If the units
 457                                 are not running yet the operation
 458                                 will fail. Note that for
 459                                 compatibility with SysV init scripts
 460                                 <command>force-reload</command> is
 461                                 equivalent to this command.</para></listitem>
 462                         </varlistentry>
 463                         <varlistentry>
 464                                 <term><command>isolate [NAME]</command></term>
 465
 466                                 <listitem><para>Start the unit
 467                                 specified on the command line and its
 468                                 dependencies and stop all others.</para>
 469
 470                                 <para>This is similar to changing the
 471                                 runlevel in a traditional init system. The
 472                                 <command>isolate</command> command will
 473                                 immediately stop processes that are not
 474                                 enabled in the new unit, possibly including
 475                                 the graphical environment or terminal you
 476                                 are currently using.</para>
 477
 478                                 <para>Note that this works only on units
 479                                 where <option>AllowIsolate=</option> is
 480                                 enabled. See
 481                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 482                                 for details.</para></listitem>
 483                         </varlistentry>
 484                         <varlistentry>
 485                                 <term><command>kill [NAME...]</command></term>
 486
 487                                 <listitem><para>Send a signal to one
 488                                 or more processes of the unit. Use
 489                                 <option>--kill-who=</option> to select
 490                                 which process to kill. Use
 491                                 <option>--kill-mode=</option> to
 492                                 select the kill mode and
 493                                 <option>--signal=</option> to select
 494                                 the signal to send.</para></listitem>
 495                         </varlistentry>
 496                         <varlistentry>
 497                                 <term><command>is-active [NAME...]</command></term>
 498
 499                                 <listitem><para>Check whether any of
 500                                 the specified units are active
 501                                 (i.e. running). Returns an exit code
 502                                 0 if at least one is active, non-zero
 503                                 otherwise. Unless
 504                                 <option>--quiet</option> is specified
 505                                 this will also print the current unit
 506                                 state to STDOUT.</para></listitem>
 507                         </varlistentry>
 508                         <varlistentry>
 509                                 <term><command>status [NAME...|PID...]</command></term>
 510
 511                                 <listitem><para>Show terse runtime
 512                                 status information about one or more
 513                                 units. This function is intended to
 514                                 generate human-readable output. If you
 515                                 are looking for computer-parsable
 516                                 output, use <command>show</command>
 517                                 instead. If a PID is passed
 518                                 information about the unit the process
 519                                 of the PID belongs to is
 520                                 shown.</para></listitem>
 521                         </varlistentry>
 522                         <varlistentry>
 523                                 <term><command>show [NAME...|JOB...]</command></term>
 524
 525                                 <listitem><para>Show properties of one
 526                                 or more units, jobs or the manager
 527                                 itself. If no argument is specified
 528                                 properties of the manager will be
 529                                 shown. If a unit name is specified
 530                                 properties of the unit is shown, and
 531                                 if a job id is specified properties of
 532                                 the job is shown. By default, empty
 533                                 properties are suppressed. Use
 534                                 <option>--all</option> to show those
 535                                 too. To select specific properties to
 536                                 show use
 537                                 <option>--property=</option>. This
 538                                 command is intended to be used
 539                                 whenever computer-parsable output is
 540                                 required. Use
 541                                 <command>status</command> if you are
 542                                 looking for formatted human-readable
 543                                 output.</para></listitem>
 544                         </varlistentry>
 545
 546                         <varlistentry>
 547                                 <term><command>reset-failed [NAME...]</command></term>
 548
 549                                 <listitem><para>Reset the
 550                                 '<literal>failed</literal>' state of the
 551                                 specified units, or if no unit name is
 552                                 passed of all units. When a unit fails
 553                                 in some way (i.e. process exiting with
 554                                 non-zero error code, terminating
 555                                 abnormally or timing out) it will
 556                                 automatically enter the
 557                                 '<literal>failed</literal>' state and
 558                                 its exit code and status is recorded
 559                                 for introspection by the administrator
 560                                 until the service is restarted or
 561                                 reset with this
 562                                 command.</para></listitem>
 563                         </varlistentry>
 564
 565                         <varlistentry>
 566                                 <term><command>enable [NAME...]</command></term>
 567
 568                                 <listitem><para>Enable one or more
 569                                 unit files, as specified on the
 570                                 command line. This will create a
 571                                 number of symlinks as encoded in the
 572                                 <literal>[Install]</literal> sections
 573                                 of the unit files. After the symlinks
 574                                 have been created the systemd
 575                                 configuration is reloaded (in a way
 576                                 that is equivalent to
 577                                 <command>daemon-reload</command>) to
 578                                 ensure the changes are taken into
 579                                 account immediately. Note that this
 580                                 does not have the effect that any of
 581                                 the units enabled are also started at
 582                                 the same time. If this is desired a
 583                                 separate <command>start</command>
 584                                 command must be invoked for the
 585                                 unit.</para>
 586
 587                                 <para>This command will
 588                                 print the actions executed. This
 589                                 output may be suppressed by passing
 590                                 <option>--quiet</option>.</para>
 591
 592                                 <para>Note that this operation creates
 593                                 only the suggested symlinks for the
 594                                 units. While this command is the
 595                                 recommended way to manipulate the unit
 596                                 configuration directory, the
 597                                 administrator is free to make
 598                                 additional changes manually, by
 599                                 placing or removing symlinks in the
 600                                 directory. This is particularly useful
 601                                 to create configurations that deviate
 602                                 from the suggested default
 603                                 installation. In this case the
 604                                 administrator must make sure to invoke
 605                                 <command>daemon-reload</command>
 606                                 manually as necessary, to ensure his
 607                                 changes are taken into account.</para>
 608
 609                                 <para>Enabling units should not be
 610                                 confused with starting (activating)
 611                                 units, as done by the
 612                                 <command>start</command>
 613                                 command. Enabling and starting units
 614                                 is orthogonal: units may be enabled
 615                                 without being started and started
 616                                 without being enabled. Enabling simply
 617                                 hooks the unit into various suggested
 618                                 places (for example, so that the unit
 619                                 is automatically started on boot or
 620                                 when a particular kind of hardware is
 621                                 plugged in). Starting actually spawns
 622                                 the daemon process (in case of service
 623                                 units), or binds the socket (in case
 624                                 of socket units), and so
 625                                 on.</para>
 626
 627                                 <para>Depending on whether
 628                                 <option>--system</option>,
 629                                 <option>--user</option> or
 630                                 <option>--global</option> is specified
 631                                 this enables the unit for the system,
 632                                 for the calling user only
 633                                 or for all future logins of all
 634                                 users. Note that in the latter case no
 635                                 systemd daemon configuration is
 636                                 reloaded.</para>
 637                                 </listitem>
 638                         </varlistentry>
 639
 640                         <varlistentry>
 641                                 <term><command>disable [NAME...]</command></term>
 642
 643                                 <listitem><para>Disables one or more
 644                                 units. This removes all symlinks to
 645                                 the specified unit files from the unit
 646                                 configuration directory, and hence
 647                                 undoes the changes made by
 648                                 <command>enable</command>. Note
 649                                 however that this by default removes
 650                                 all symlinks to the unit files
 651                                 (i.e. including manual additions), not
 652                                 just those actually created by
 653                                 <command>enable</command>. If only the
 654                                 symlinks that are suggested by default
 655                                 shall be removed, pass
 656                                 <option>--defaults</option>. This
 657                                 implicitly reloads the systemd daemon
 658                                 configuration after completing the
 659                                 disabling of the units. Note that this
 660                                 command does not implicitly stop the
 661                                 units that is being disabled. If this
 662                                 is desired an additional
 663                                 <command>stop</command>command should
 664                                 be executed afterwards.</para>
 665
 666                                 <para>This command will print the
 667                                 actions executed. This output may be
 668                                 suppressed by passing
 669                                 <option>--quiet</option>.</para>
 670                                 </listitem>
 671
 672                                 <para>This command honors
 673                                 <option>--system</option>,
 674                                 <option>--user</option>,
 675                                 <option>--global</option> in a similar
 676                                 way as
 677                                 <command>enable</command>.</para>
 678                         </varlistentry>
 679
 680                         <varlistentry>
 681                                 <term><command>is-enabled [NAME...]</command></term>
 682
 683                                 <listitem><para>Checks whether any of
 684                                 the specified unit files is enabled
 685                                 (as with
 686                                 <command>enable</command>). Returns an
 687                                 exit code of 0 if at least one is
 688                                 enabled, non-zero
 689                                 otherwise.</para></listitem>
 690                         </varlistentry>
 691
 692                         <varlistentry>
 693                                 <term><command>load [NAME...]</command></term>
 694
 695                                 <listitem><para>Load one or more units
 696                                 specified on the command line. This
 697                                 will simply load their configuration
 698                                 from disk, but not start them. To
 699                                 start them you need to use the
 700                                 <command>start</command> command which
 701                                 will implicitly load a unit that has
 702                                 not been loaded yet. Note that systemd
 703                                 garbage collects loaded units that are
 704                                 not active or referenced by an active
 705                                 unit. This means that units loaded
 706                                 this way will usually not stay loaded
 707                                 for long. Also note that this command
 708                                 cannot be used to reload unit
 709                                 configuration. Use the
 710                                 <command>daemon-reload</command>
 711                                 command for that. All in all, this
 712                                 command is of little use except for
 713                                 debugging.</para>
 714                                 <para>This command should not be
 715                                 confused with the
 716                                 <command>daemon-reload</command> or
 717                                 <command>reload</command>
 718                                 commands.</para></listitem>
 719                         </varlistentry>
 720                         <varlistentry>
 721                                 <term><command>list-jobs</command></term>
 722
 723                                 <listitem><para>List jobs that are in progress.</para></listitem>
 724                         </varlistentry>
 725                         <varlistentry>
 726                                 <term><command>cancel [JOB...]</command></term>
 727
 728                                 <listitem><para>Cancel one or more
 729                                 jobs specified on the command line by
 730                                 their numeric job
 731                                 IDs. If no job id is specified, cancel all pending jobs.</para></listitem>
 732                         </varlistentry>
 733                         <varlistentry>
 734                                 <term><command>monitor</command></term>
 735
 736                                 <listitem><para>Monitor unit/job
 737                                 changes. This is mostly useful for
 738                                 debugging purposes and prints a line
 739                                 each time systemd loads or unloads a
 740                                 unit configuration file, or a unit
 741                                 property changes.</para></listitem>
 742                         </varlistentry>
 743                         <varlistentry>
 744                                 <term><command>dump</command></term>
 745
 746                                 <listitem><para>Dump server
 747                                 status. This will output a (usually
 748                                 very long) human readable manager
 749                                 status dump. Its format is subject to
 750                                 change without notice and should not
 751                                 be parsed by
 752                                 applications.</para></listitem>
 753                         </varlistentry>
 754                         <varlistentry>
 755                                 <term><command>dot</command></term>
 756
 757                                 <listitem><para>Generate textual
 758                                 dependency graph description in dot
 759                                 format for further processing with the
 760                                 GraphViz
 761                                 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 762                                 tool. Use a command line like
 763                                 <command>systemctl dot | dot -Tsvg >
 764                                 systemd.svg</command> to generate a
 765                                 graphical dependency tree. Unless
 766                                 <option>--order</option> or
 767                                 <option>--require</option> is passed
 768                                 the generated graph will show both
 769                                 ordering and requirement
 770                                 dependencies.</para></listitem>
 771                         </varlistentry>
 772                         <varlistentry>
 773                                 <term><command>snapshot [NAME]</command></term>
 774
 775                                 <listitem><para>Create a snapshot. If
 776                                 a snapshot name is specified, the new
 777                                 snapshot will be named after it. If
 778                                 none is specified an automatic
 779                                 snapshot name is generated. In either
 780                                 case, the snapshot name used is
 781                                 printed to STDOUT, unless
 782                                 <option>--quiet</option> is
 783                                 specified.</para>
 784
 785                                 <para>A snapshot refers to a saved
 786                                 state of the systemd manager. It is
 787                                 implemented itself as a unit that is
 788                                 generated dynamically with this
 789                                 command and has dependencies on all
 790                                 units active at the time. At a later
 791                                 time the user may return to this state
 792                                 by using the
 793                                 <command>isolate</command> command on
 794                                 the snapshot unit.</para></listitem>
 795
 796                                 <para>Snapshots are only useful for
 797                                 saving and restoring which units are
 798                                 running or are stopped, they do not
 799                                 save/restore any other
 800                                 state. Snapshots are dynamic and lost
 801                                 on reboot.</para>
 802                         </varlistentry>
 803                         <varlistentry>
 804                                 <term><command>delete [NAME...]</command></term>
 805
 806                                 <listitem><para>Remove a snapshot
 807                                 previously created with
 808                                 <command>snapshot</command>.</para></listitem>
 809                         </varlistentry>
 810                         <varlistentry>
 811                                 <term><command>daemon-reload</command></term>
 812
 813                                 <listitem><para>Reload systemd manager
 814                                 configuration. This will reload all
 815                                 unit files and recreate the entire
 816                                 dependency tree. While the daemon is
 817                                 reloaded, all sockets systemd listens
 818                                 on on behalf of user configuration will
 819                                 stay accessible.</para> <para>This
 820                                 command should not be confused with
 821                                 the <command>load</command> or
 822                                 <command>reload</command>
 823                                 commands.</para></listitem>
 824                         </varlistentry>
 825                         <varlistentry>
 826                                 <term><command>daemon-reexec</command></term>
 827
 828                                 <listitem><para>Reexecute the systemd
 829                                 manager. This will serialize the
 830                                 manager state, reexecute the process
 831                                 and deserialize the state again. This
 832                                 command is of little use except for
 833                                 debugging and package
 834                                 upgrades. Sometimes it might be
 835                                 helpful as a heavy-weight
 836                                 <command>daemon-reload</command>. While
 837                                 the daemon is reexecuted all sockets
 838                                 systemd listens on on behalf of user
 839                                 configuration will stay
 840                                 accessible.</para></listitem>
 841                         </varlistentry>
 842                         <varlistentry>
 843                                 <term><command>show-environment</command></term>
 844
 845                                 <listitem><para>Dump the systemd
 846                                 manager environment block. The
 847                                 environment block will be dumped in
 848                                 straight-forward form suitable for
 849                                 sourcing into a shell script. This
 850                                 environment block will be passed to
 851                                 all processes the manager
 852                                 spawns.</para></listitem>
 853                         </varlistentry>
 854                         <varlistentry>
 855                                 <term><command>set-environment [NAME=VALUE...]</command></term>
 856
 857                                 <listitem><para>Set one or more
 858                                 systemd manager environment variables,
 859                                 as specified on the command
 860                                 line.</para></listitem>
 861                         </varlistentry>
 862                         <varlistentry>
 863                                 <term><command>unset-environment [NAME...]</command></term>
 864
 865                                 <listitem><para>Unset one or more
 866                                 systemd manager environment
 867                                 variables. If only a variable name is
 868                                 specified it will be removed
 869                                 regardless of its value. If a variable
 870                                 and a value are specified the variable
 871                                 is only removed if it has the
 872                                 specified value.</para></listitem>
 873                         </varlistentry>
 874                         <varlistentry>
 875                                 <term><command>default</command></term>
 876
 877                                 <listitem><para>Enter default
 878                                 mode. This is mostly equivalent to
 879                                 <command>start
 880                                 default.target</command>.</para></listitem>
 881                         </varlistentry>
 882                         <varlistentry>
 883                                 <term><command>rescue</command></term>
 884
 885                                 <listitem><para>Enter rescue
 886                                 mode. This is mostly equivalent to
 887                                 <command>isolate
 888                                 rescue.target</command> but also
 889                                 prints a wall message to all
 890                                 users.</para></listitem>
 891                         </varlistentry>
 892                         <varlistentry>
 893                                 <term><command>emergency</command></term>
 894
 895                                 <listitem><para>Enter emergency
 896                                 mode. This is mostly equivalent to
 897                                 <command>isolate
 898                                 emergency.target</command> but also
 899                                 prints a wall message to all
 900                                 users.</para></listitem>
 901                         </varlistentry>
 902                         <varlistentry>
 903                                 <term><command>halt</command></term>
 904
 905                                 <listitem><para>Shut down and halt the
 906                                 system. This is mostly equivalent to
 907                                 <command>start halt.target</command>
 908                                 but also prints a wall message to all
 909                                 users.  If
 910                                 combined with <option>--force</option>
 911                                 shutdown of all running services is
 912                                 skipped, however all processes are killed
 913                                 and all file systems are unmounted or
 914                                 mounted read-only, immediately
 915                                 followed by the
 916                                 system halt.</para></listitem>
 917                         </varlistentry>
 918                         <varlistentry>
 919                                 <term><command>poweroff</command></term>
 920
 921                                 <listitem><para>Shut down and
 922                                 power-off the system. This is mostly
 923                                 equivalent to <command>start
 924                                 poweroff.target</command> but also
 925                                 prints a wall message to all
 926                                 users. If
 927                                 combined with <option>--force</option>
 928                                 shutdown of all running services is
 929                                 skipped, however all processes are killed
 930                                 and all file systems are unmounted or
 931                                 mounted read-only, immediately
 932                                 followed by the
 933                                 powering off.</para></listitem>
 934                         </varlistentry>
 935                         <varlistentry>
 936                                 <term><command>reboot</command></term>
 937
 938                                 <listitem><para>Shut down and
 939                                 reboot the system. This is mostly
 940                                 equivalent to <command>start
 941                                 reboot.target</command> but also
 942                                 prints a wall message to all
 943                                 users. If
 944                                 combined with <option>--force</option>
 945                                 shutdown of all running services is
 946                                 skipped, however all processes are killed
 947                                 and all file systems are unmounted or
 948                                 mounted read-only, immediately
 949                                 followed by the
 950                                 reboot.</para></listitem>
 951                         </varlistentry>
 952                         <varlistentry>
 953                                 <term><command>kexec</command></term>
 954
 955                                 <listitem><para>Shut down and reboot
 956                                 the system via kexec. This is mostly
 957                                 equivalent to <command>start
 958                                 kexec.target</command> but also prints
 959                                 a wall message to all users. If
 960                                 combined with <option>--force</option>
 961                                 shutdown of all running services is
 962                                 skipped, however all processes are killed
 963                                 and all file systems are unmounted or
 964                                 mounted read-only, immediately
 965                                 followed by the
 966                                 reboot.</para></listitem>
 967                         </varlistentry>
 968                         <varlistentry>
 969                                 <term><command>exit</command></term>
 970
 971                                 <listitem><para>Ask the systemd
 972                                 manager to quit. This is only
 973                                 supported for user service managers
 974                                 (i.e. in conjunction with the
 975                                 <option>--user</option> option) and
 976                                 will fail otherwise.</para></listitem>
 977                         </varlistentry>
 978                 </variablelist>
 979
 980         </refsect1>
 981
 982         <refsect1>
 983                 <title>Exit status</title>
 984
 985                 <para>On success 0 is returned, a non-zero failure
 986                 code otherwise.</para>
 987         </refsect1>
 988
 989         <refsect1>
 990                 <title>See Also</title>
 991                 <para>
 992                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 993                         <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 994                         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 995                         <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 996                         <citerefentry><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 997                 </para>
 998         </refsect1>
 999
1000 </refentry>