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.
  19
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  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 session 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 session 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>--type=</option></term>
  81                                 <term><option>-t</option></term>
  82
  83                                 <listitem><para>When listing units,
  84                                 limit display to certain unit
  85                                 types. If not specified units of all
  86                                 types will be shown. The argument
  87                                 should be a unit type name such as
  88                                 <option>service</option>,
  89                                 <option>socket</option> and
  90                                 similar.</para></listitem>
  91                         </varlistentry>
  92
  93                         <varlistentry>
  94                                 <term><option>--property=</option></term>
  95                                 <term><option>-p</option></term>
  96
  97                                 <listitem><para>When showing
  98                                 unit/job/manager information, limit
  99                                 display to certain properties as
 100                                 specified as argument. If not
 101                                 specified all set properties are
 102                                 shown. The argument should be a
 103                                 property name, such as
 104                                 <literal>MainPID</literal>. If
 105                                 specified more than once all
 106                                 properties with the specified names
 107                                 are shown.</para></listitem>
 108                         </varlistentry>
 109
 110                         <varlistentry>
 111                                 <term><option>--all</option></term>
 112                                 <term><option>-a</option></term>
 113
 114                                 <listitem><para>When listing units,
 115                                 show all units, regardless of their
 116                                 state, including inactive units. When
 117                                 showing unit/job/manager information,
 118                                 show all properties regardless whether
 119                                 they are set or not.</para></listitem>
 120                         </varlistentry>
 121
 122                         <varlistentry>
 123                                 <term><option>--full</option></term>
 124
 125                                 <listitem><para>Do not ellipsize unit
 126                                 names and truncate unit descriptions
 127                                 in the output of
 128                                 <command>list-units</command> and
 129                                 <command>list-jobs</command>.</para></listitem>
 130                         </varlistentry>
 131
 132                         <varlistentry>
 133                                 <term><option>--fail</option></term>
 134
 135                                 <listitem><para>If the requested
 136                                 operation conflicts with a pending
 137                                 unfinished job, fail the command. If
 138                                 this is not specified the requested
 139                                 operation will replace the pending job,
 140                                 if necessary.</para></listitem>
 141                         </varlistentry>
 142
 143                         <varlistentry>
 144                                 <term><option>--quiet</option></term>
 145                                 <term><option>-q</option></term>
 146
 147                                 <listitem><para>Suppress output to
 148                                 STDOUT in
 149                                 <command>snapshot</command>,
 150                                 <command>check</command>,
 151                                 <command>enable</command> and
 152                                 <command>disable</command>.</para></listitem>
 153                         </varlistentry>
 154
 155                         <varlistentry>
 156                                 <term><option>--no-block</option></term>
 157
 158                                 <listitem><para>Do not synchronously wait for
 159                                 the requested operation to finish. If this is
 160                                 not specified the job will be verified,
 161                                 enqueued and <command>systemctl</command> will
 162                                 wait until it is completed. By passing this
 163                                 argument it is only verified and
 164                                 enqueued.</para></listitem> </varlistentry>
 165
 166                         <varlistentry>
 167                                 <term><option>--system</option></term>
 168
 169                                 <listitem><para>Talk to the systemd
 170                                 system manager. (Default)</para></listitem>
 171                         </varlistentry>
 172
 173                         <varlistentry>
 174                                 <term><option>--session</option></term>
 175
 176                                 <listitem><para>Talk to the systemd
 177                                 session manager of the calling user.</para></listitem>
 178                         </varlistentry>
 179
 180                         <varlistentry>
 181                                 <term><option>--order</option></term>
 182                                 <term><option>--require</option></term>
 183
 184                                 <listitem><para>When used in
 185                                 conjunction with the
 186                                 <command>dot</command> command (see
 187                                 below), selects which dependencies are
 188                                 shown in the dependency graph. If
 189                                 <option>--order</option> is passed
 190                                 only dependencies of type
 191                                 <varname>After=</varname> or
 192                                 <varname>Before=</varname> are
 193                                 shown. If <option>--require</option>
 194                                 is passed only dependencies of type
 195                                 <varname>Requires=</varname>,
 196                                 <varname>RequiresOverridable=</varname>,
 197                                 <varname>Requisite=</varname>,
 198                                 <varname>RequisiteOverridable=</varname>,
 199                                 <varname>Wants=</varname> and
 200                                 <varname>Conflicts=</varname> are
 201                                 shown. If neither is passed, shows
 202                                 dependencies of all these
 203                                 types.</para></listitem>
 204                         </varlistentry>
 205
 206                         <varlistentry>
 207                                 <term><option>--no-wall</option></term>
 208
 209                                 <listitem><para>Don't send wall
 210                                 message before
 211                                 halt, power-off, reboot.</para></listitem>
 212                         </varlistentry>
 213
 214                         <varlistentry>
 215                                 <term><option>--global</option></term>
 216
 217                                 <listitem><para>When used with
 218                                 <command>enable</command> and
 219                                 <command>disable</command>, operate on the
 220                                 global session configuŕation
 221                                 directory, thus enabling or disabling
 222                                 a unit file globally for all future
 223                                 sessions of all users.</para></listitem>
 224                         </varlistentry>
 225
 226                         <varlistentry>
 227                                 <term><option>--no-reload</option></term>
 228
 229                                 <listitem><para>When used with
 230                                 <command>enable</command> and
 231                                 <command>disable</command>, do not
 232                                 implicitly reload daemon configuration
 233                                 after executing the
 234                                 changes.</para></listitem>
 235                         </varlistentry>
 236
 237                         <varlistentry>
 238                                 <term><option>--force</option></term>
 239
 240                                 <listitem><para>When used with
 241                                 <command>enable</command>, override any
 242                                 existing conflicting
 243                                 symlinks.</para></listitem>
 244                         </varlistentry>
 245
 246                         <varlistentry>
 247                                 <term><option>--defaults</option></term>
 248
 249                                 <listitem><para>When used with
 250                                 <command>disable</command>, ensures
 251                                 that only the symlinks created by
 252                                 <command>enable</command> are removed,
 253                                 not all symlinks pointing to the unit
 254                                 file that shall be
 255                                 disabled.</para></listitem>
 256                         </varlistentry>
 257                 </variablelist>
 258
 259                 <para>The following commands are understood:</para>
 260
 261                 <variablelist>
 262                         <varlistentry>
 263                                 <term><command>list-units</command></term>
 264
 265                                 <listitem><para>List known units.</para></listitem>
 266                         </varlistentry>
 267                         <varlistentry>
 268                                 <term><command>start [NAME...]</command></term>
 269
 270                                 <listitem><para>Start (activate) one
 271                                 or more units specified on the command
 272                                 line.</para></listitem>
 273                         </varlistentry>
 274                         <varlistentry>
 275                                 <term><command>stop [NAME...]</command></term>
 276
 277                                 <listitem><para>Stop (deactivate) one
 278                                 or more units specified on the command
 279                                 line.</para></listitem>
 280                         </varlistentry>
 281                         <varlistentry>
 282                                 <term><command>reload [NAME...]</command></term>
 283
 284                                 <listitem><para>Asks all units listed
 285                                 on the command line to reload their
 286                                 configuration. Note that this will
 287                                 reload the service-specific
 288                                 configuration, not the unit
 289                                 configuration file of systemd. If you
 290                                 want systemd to reload the
 291                                 configuration file of a unit use the
 292                                 <command>daemon-reload</command>
 293                                 command. In other words: for the
 294                                 example case of Apache, this will
 295                                 reload Apache's
 296                                 <filename>httpd.conf</filename> in the
 297                                 web server, not the
 298                                 <filename>apache.service</filename>
 299                                 systemd unit file. </para>
 300
 301                                 <para>This command should not be
 302                                 confused with the
 303                                 <command>daemon-reload</command> or
 304                                 <command>load</command>
 305                                 commands.</para></listitem>
 306
 307                         </varlistentry>
 308                         <varlistentry>
 309                                 <term><command>restart [NAME...]</command></term>
 310
 311                                 <listitem><para>Restart one or more
 312                                 units specified on the command
 313                                 line. If the units are not running yet
 314                                 they will be
 315                                 started.</para></listitem>
 316                         </varlistentry>
 317                         <varlistentry>
 318                                 <term><command>try-restart [NAME...]</command></term>
 319
 320                                 <listitem><para>Restart one or more
 321                                 units specified on the command
 322                                 line. If the units are not running yet
 323                                 the operation will
 324                                 fail.</para></listitem>
 325                         </varlistentry>
 326                         <varlistentry>
 327                                 <term><command>reload-or-restart [NAME...]</command></term>
 328                                 <term><command>reload-or-try-restart [NAME...]</command></term>
 329
 330                                 <listitem><para>Reload one or more
 331                                 units if they support it. If not,
 332                                 restart them instead. Note that for
 333                                 compatibility with SysV and Red Hat
 334                                 init scripts
 335                                 <command>force-reload</command> and
 336                                 <command>condrestart</command> may be
 337                                 used as equivalent commands to
 338                                 <command>reload-or-try-restart</command>.</para></listitem>
 339                         </varlistentry>
 340                         <varlistentry>
 341                                 <term><command>isolate [NAME]</command></term>
 342
 343                                 <listitem><para>Start the unit
 344                                 specified on the command line and its
 345                                 dependencies and stop all others.</para>
 346
 347                                 <para>This is similar to changing the
 348                                 runlevel in a traditional init system. The
 349                                 <command>isolate</command> command will
 350                                 immediately stop processes that are not
 351                                 enabled in the new unit, possibly including
 352                                 the graphical environment or terminal you
 353                                 are currently using.</para>
 354
 355                                 <para>Note that this works only on units
 356                                 where <option>AllowIsolate=</option> is
 357                                 enabled. See
 358                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 359                                 for details.</para></listitem>
 360                         </varlistentry>
 361                         <varlistentry>
 362                                 <term><command>is-active [NAME...]</command></term>
 363
 364                                 <listitem><para>Check whether any of
 365                                 the specified units is active
 366                                 (i.e. running). Returns an exit code
 367                                 0 if at least one is active, non-zero
 368                                 otherwise. Unless
 369                                 <option>--quiet</option> is specified
 370                                 this will also print the current unit
 371                                 state to STDOUT.</para></listitem>
 372                         </varlistentry>
 373                         <varlistentry>
 374                                 <term><command>status [NAME...|PID...]</command></term>
 375
 376                                 <listitem><para>Show terse runtime
 377                                 status information about one or more
 378                                 units. This function is intended to
 379                                 generate human-readable output. If you
 380                                 are looking for computer-parsable
 381                                 output, use <command>show</command>
 382                                 instead. If a PID is passed
 383                                 information about the unit the process
 384                                 of the PID belongs to is
 385                                 shown.</para></listitem>
 386                         </varlistentry>
 387                         <varlistentry>
 388                                 <term><command>show [NAME...|JOB...]</command></term>
 389
 390                                 <listitem><para>Show properties of one
 391                                 or more units, jobs or the manager
 392                                 itself. If no argument is specified
 393                                 properties of the manager will be
 394                                 shown. If a unit name is specified
 395                                 properties of the unit is shown, and
 396                                 if a job id is specified properties of
 397                                 the job is shown. By default, empty
 398                                 properties are suppressed. Use
 399                                 <option>--all</option> to show those
 400                                 too. To select specific properties to
 401                                 show use
 402                                 <option>--property=</option>. This
 403                                 command is intended to be used
 404                                 whenever computer-parsable output is
 405                                 required. Use
 406                                 <command>status</command> if you are
 407                                 looking for formatted human-readable
 408                                 output.</para></listitem>
 409                         </varlistentry>
 410
 411                         <varlistentry>
 412                                 <term><command>reset-failed [NAME...]</command></term>
 413
 414                                 <listitem><para>Reset the
 415                                 '<literal>failed</literal>' state of the
 416                                 specified units, or if no unit name is
 417                                 passed of all units. When a unit fails
 418                                 in some way (i.e. process exiting with
 419                                 non-zero error code, terminating
 420                                 abnormally or timing out) it will
 421                                 automatically enter the
 422                                 '<literal>failed</literal>' state and
 423                                 its exit code and status is recorded
 424                                 for introspection by the administrator
 425                                 until the service is restarted or
 426                                 reset with this
 427                                 command.</para></listitem>
 428                         </varlistentry>
 429
 430                         <varlistentry>
 431                                 <term><command>enable [NAME...]</command></term>
 432
 433                                 <listitem><para>Enable one or more
 434                                 unit files, as specified on the
 435                                 command line. This will create a
 436                                 number of symlinks as encoded in the
 437                                 <literal>[Install]</literal> sections
 438                                 of the unit files. After the symlinks
 439                                 have been created the systemd
 440                                 configuration is reloaded (in a way
 441                                 that is equivalent to
 442                                 <command>daemon-reload</command>) to
 443                                 ensure the changes are taken into
 444                                 account immediately. Note that this
 445                                 does not have the effect that any of
 446                                 the units enabled are also started at
 447                                 the same time. If this is desired a
 448                                 separate <command>start</command>
 449                                 command must be invoked for the
 450                                 unit.</para>
 451
 452                                 <para>This command will
 453                                 print the actions executed. This
 454                                 output may be suppressed by passing
 455                                 <option>--quiet</option>.</para>
 456
 457                                 <para>Note that this operation creates
 458                                 only the suggested symlinks for the
 459                                 units. While this command is the
 460                                 recommended way to manipulate the unit
 461                                 configuration directory, the
 462                                 administrator is free to make
 463                                 additional changes manually, by
 464                                 placing or removing symlinks in the
 465                                 directory. This is particular useful
 466                                 to create configurations that deviate
 467                                 from the suggested default
 468                                 installation. In this case the
 469                                 administrator must make sure to invoke
 470                                 <command>daemon-reload</command>
 471                                 manually as necessary, to ensure his
 472                                 changes are taken into account.</para>
 473
 474                                 <para>Enabling units should not be
 475                                 confused with starting (activating)
 476                                 units, as done by the
 477                                 <command>start</command>
 478                                 command. Enabling and starting units
 479                                 is orthogonal: units may be enabled
 480                                 without being started and started
 481                                 without being enabled. Enabling simply
 482                                 hooks the unit into various suggested
 483                                 places (for example, so that the unit
 484                                 is automatically started on boot or
 485                                 when a particular kind of hardware is
 486                                 plugged in). Starting actually spawns
 487                                 the daemon process (in case of service
 488                                 units), or binds the socket (in case
 489                                 of socket units), and so
 490                                 on.</para>
 491
 492                                 <para>Depending on whether
 493                                 <option>--system</option>,
 494                                 <option>--session</option> or
 495                                 <option>--global</option> is specified
 496                                 this enables the unit for the system,
 497                                 for sessions of the calling user only
 498                                 or for all future session of all
 499                                 users. Note that in the latter case no
 500                                 systemd daemon configuration is
 501                                 reloaded.</para>
 502                                 </listitem>
 503                         </varlistentry>
 504
 505                         <varlistentry>
 506                                 <term><command>disable [NAME...]</command></term>
 507
 508                                 <listitem><para>Disables one or more
 509                                 units. This removes all symlinks to
 510                                 the specified unit files from the unit
 511                                 configuration directory, and hence
 512                                 undoes the changes made by
 513                                 <command>enable</command>. Note
 514                                 however that this by default removes
 515                                 all symlinks to the unit files
 516                                 (i.e. including manual additions), not
 517                                 just those actually created by
 518                                 <command>enable</command>. If only the
 519                                 symlinks that are suggested by default
 520                                 shall be removed, pass
 521                                 <option>--defaults</option>. This
 522                                 implicitly reloads the systemd daemon
 523                                 configuration after completing the
 524                                 disabling of the units. Note that this
 525                                 command does not implicitly stop the
 526                                 units that is being disabled. If this
 527                                 is desired an additional
 528                                 <command>stop</command>command should
 529                                 be executed afterwards.</para>
 530
 531                                 <para>This command will print the
 532                                 actions executed. This output may be
 533                                 suppressed by passing
 534                                 <option>--quiet</option>.</para>
 535                                 </listitem>
 536
 537                                 <para>This command honours
 538                                 <option>--system</option>,
 539                                 <option>--session</option>,
 540                                 <option>--global</option> in a similar
 541                                 way as
 542                                 <command>enable</command>.</para>
 543                         </varlistentry>
 544
 545                         <varlistentry>
 546                                 <term><command>is-enabled [NAME...]</command></term>
 547
 548                                 <listitem><para>Checks whether any of
 549                                 the specified unit files is enabled
 550                                 (as with
 551                                 <command>enable</command>). Returns an
 552                                 exit code of 0 if at least one is
 553                                 enabled, non-zero
 554                                 otherwise.</para></listitem>
 555                         </varlistentry>
 556
 557                         <varlistentry>
 558                                 <term><command>load [NAME...]</command></term>
 559
 560                                 <listitem><para>Load one or more units
 561                                 specified on the command line. This
 562                                 will simply load their configuration
 563                                 from disk, but not start them. To
 564                                 start them you need to use the
 565                                 <command>start</command> command which
 566                                 will implicitly load a unit that has
 567                                 not been loaded yet. Note that systemd
 568                                 garbage collects loaded units that are
 569                                 not active or referenced by an active
 570                                 unit. This means that units loaded
 571                                 this way will usually not stay loaded
 572                                 for long. Also note that this command
 573                                 cannot be used to reload unit
 574                                 configuration. Use the
 575                                 <command>daemon-reload</command>
 576                                 command for that. All in all, this
 577                                 command is of little use except for
 578                                 debugging.</para>
 579                                 <para>This command should not be
 580                                 confused with the
 581                                 <command>daemon-reload</command> or
 582                                 <command>reload</command>
 583                                 commands.</para></listitem>
 584                         </varlistentry>
 585                         <varlistentry>
 586                                 <term><command>list-jobs</command></term>
 587
 588                                 <listitem><para>List jobs that are in progress.</para></listitem>
 589                         </varlistentry>
 590                         <varlistentry>
 591                                 <term><command>cancel [JOB...]</command></term>
 592
 593                                 <listitem><para>Cancel one or more
 594                                 jobs specified on the command line by
 595                                 their numeric job
 596                                 IDs. If not job id is specified cancels all jobs that are pending.</para></listitem>
 597                         </varlistentry>
 598                         <varlistentry>
 599                                 <term><command>monitor</command></term>
 600
 601                                 <listitem><para>Monitor unit/job
 602                                 changes. This is mostly useful for
 603                                 debugging purposes and prints a line
 604                                 each time systemd loads or unloads a
 605                                 unit configuration file, or a unit
 606                                 property changes.</para></listitem>
 607                         </varlistentry>
 608                         <varlistentry>
 609                                 <term><command>dump</command></term>
 610
 611                                 <listitem><para>Dump server
 612                                 status. This will output a (usually
 613                                 very long) human readable manager
 614                                 status dump. Its format is subject to
 615                                 change without notice and should not
 616                                 be parsed by
 617                                 applications.</para></listitem>
 618                         </varlistentry>
 619                         <varlistentry>
 620                                 <term><command>dot</command></term>
 621
 622                                 <listitem><para>Generate textual
 623                                 dependency graph description in dot
 624                                 format for further processing with the
 625                                 GraphViz
 626                                 <citerefentry><refentrytitle>dot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 627                                 tool. Use a command line like
 628                                 <command>systemctl dot | dot -Tsvg >
 629                                 systemd.svg</command> to generate a
 630                                 graphical dependency tree. Unless
 631                                 <option>--order</option> or
 632                                 <option>--require</option> is passed
 633                                 the generated graph will show both
 634                                 ordering and requirement
 635                                 dependencies.</para></listitem>
 636                         </varlistentry>
 637                         <varlistentry>
 638                                 <term><command>snapshot [NAME]</command></term>
 639
 640                                 <listitem><para>Create a snapshot. If
 641                                 a snapshot name is specified, the new
 642                                 snapshot will be named after it. If
 643                                 none is specified an automatic
 644                                 snapshot name is generated. In either
 645                                 case, the snapshot name used is
 646                                 printed to STDOUT, unless
 647                                 <option>--quiet</option> is
 648                                 specified.</para>
 649
 650                                 <para>A snapshot refers to a saved
 651                                 state of the systemd manager. It is
 652                                 implemented itself as unit that is
 653                                 generated dynamically with this
 654                                 command and has dependencies on all
 655                                 units active at the time. At a later
 656                                 time the user may return to this state
 657                                 by using the
 658                                 <command>isolate</command> command on
 659                                 the snapshot unit.</para></listitem>
 660
 661                                 <para>Snapshots are only useful for
 662                                 saving and restoring which units are
 663                                 running or are stopped, they do not
 664                                 save/restore any other
 665                                 state. Snapshots are dynamic and lost
 666                                 on reboot.</para>
 667                         </varlistentry>
 668                         <varlistentry>
 669                                 <term><command>delete [NAME...]</command></term>
 670
 671                                 <listitem><para>Remove a snapshot
 672                                 previously created with
 673                                 <command>snapshot</command>.</para></listitem>
 674                         </varlistentry>
 675                         <varlistentry>
 676                                 <term><command>daemon-reload</command></term>
 677
 678                                 <listitem><para>Reload systemd manager
 679                                 configuration. This will reload all
 680                                 unit files and recreate the entire
 681                                 dependency tree. While the daemon is
 682                                 reloaded, all sockets systemd listens
 683                                 on on behalf of user configuration will
 684                                 stay accessible.</para> <para>This
 685                                 command should not be confused with
 686                                 the <command>load</command> or
 687                                 <command>reload</command>
 688                                 commands.</para></listitem>
 689                         </varlistentry>
 690                         <varlistentry>
 691                                 <term><command>daemon-reexec</command></term>
 692
 693                                 <listitem><para>Reexecute the systemd
 694                                 manager. This will serialize the
 695                                 manager state, reexecute the process
 696                                 and deserialize the state again. This
 697                                 command is of little use except for
 698                                 debugging and package
 699                                 upgrades. Sometimes it might be
 700                                 helpful as a heavy-weight
 701                                 <command>daemon-reload</command>. While
 702                                 the daemon is reexecuted all sockets
 703                                 systemd listens on on behalf of user
 704                                 configuration will stay
 705                                 accessible.</para></listitem>
 706                         </varlistentry>
 707                         <varlistentry>
 708                                 <term><command>daemon-exit</command></term>
 709
 710                                 <listitem><para>Ask the systemd
 711                                 manager to quit. This is only
 712                                 supported for session managers
 713                                 (i.e. in conjunction with the
 714                                 <option>--session</option> option) and
 715                                 will fail otherwise.</para></listitem>
 716                         </varlistentry>
 717                         <varlistentry>
 718                                 <term><command>show-environment</command></term>
 719
 720                                 <listitem><para>Dump the systemd
 721                                 manager environment block. The
 722                                 environment block will be dumped in
 723                                 straight-forward form suitable for
 724                                 sourcing into a shell script. This
 725                                 environment block will be passed to
 726                                 all processes the manager
 727                                 spawns.</para></listitem>
 728                         </varlistentry>
 729                         <varlistentry>
 730                                 <term><command>set-environment [NAME=VALUE...]</command></term>
 731
 732                                 <listitem><para>Set one or more
 733                                 systemd manager environment variables,
 734                                 as specified on the command
 735                                 line.</para></listitem>
 736                         </varlistentry>
 737                         <varlistentry>
 738                                 <term><command>unset-environment [NAME...]</command></term>
 739
 740                                 <listitem><para>Unset one or more
 741                                 systemd manager environment
 742                                 variables. If only a variable name is
 743                                 specified it will be removed
 744                                 regardless of its value. If a variable
 745                                 and a value are specified the variable
 746                                 is only removed if it has the
 747                                 specified value.</para></listitem>
 748                         </varlistentry>
 749
 750                         <varlistentry>
 751                                 <term><command>halt</command></term>
 752
 753                                 <listitem><para>Shut down and halt the
 754                                 system. This is mostly equivalent to
 755                                 <command>start halt.target</command>
 756                                 but also prints a wall message to all
 757                                 users.</para></listitem>
 758                         </varlistentry>
 759                         <varlistentry>
 760                                 <term><command>poweroff</command></term>
 761
 762                                 <listitem><para>Shut down and
 763                                 power-off the system. This is mostly
 764                                 equivalent to <command>start
 765                                 poweroff.target</command> but also
 766                                 prints a wall message to all
 767                                 users.</para></listitem>
 768                         </varlistentry>
 769                         <varlistentry>
 770                                 <term><command>reboot</command></term>
 771
 772                                 <listitem><para>Shut down and
 773                                 reboot the system. This is mostly
 774                                 equivalent to <command>start
 775                                 reboot.target</command> but also
 776                                 prints a wall message to all
 777                                 users.</para></listitem>
 778                         </varlistentry>
 779                         <varlistentry>
 780                                 <term><command>default</command></term>
 781
 782                                 <listitem><para>Enter default
 783                                 mode. This is mostly equivalent to
 784                                 <command>start
 785                                 default.target</command>.</para></listitem>
 786                         </varlistentry>
 787                         <varlistentry>
 788                                 <term><command>rescue</command></term>
 789
 790                                 <listitem><para>Enter rescue
 791                                 mode. This is mostly equivalent to
 792                                 <command>isolate
 793                                 rescue.target</command> but also
 794                                 prints a wall message to all
 795                                 users.</para></listitem>
 796                         </varlistentry>
 797                         <varlistentry>
 798                                 <term><command>emergency</command></term>
 799
 800                                 <listitem><para>Enter emergency
 801                                 mode. This is mostly equivalent to
 802                                 <command>isolate
 803                                 emergency.target</command> but also
 804                                 prints a wall message to all
 805                                 users.</para></listitem>
 806                         </varlistentry>
 807                 </variablelist>
 808
 809         </refsect1>
 810
 811         <refsect1>
 812                 <title>Exit status</title>
 813
 814                 <para>On success 0 is returned, a non-zero failure
 815                 code otherwise.</para>
 816         </refsect1>
 817
 818         <refsect1>
 819                 <title>See Also</title>
 820                 <para>
 821                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 822                         <citerefentry><refentrytitle>systemadm</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 823                         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 824                         <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 825                         <citerefentry><refentrytitle>wall</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 826                 </para>
 827         </refsect1>
 828
 829 </refentry>