man/systemd.special.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/>.
  22 -->
  23
  24 <refentry id="systemd.special">
  25
  26         <refentryinfo>
  27                 <title>systemd.special</title>
  28                 <productname>systemd</productname>
  29
  30                 <authorgroup>
  31                         <author>
  32                                 <contrib>Developer</contrib>
  33                                 <firstname>Lennart</firstname>
  34                                 <surname>Poettering</surname>
  35                                 <email>lennart@poettering.net</email>
  36                         </author>
  37                 </authorgroup>
  38         </refentryinfo>
  39
  40         <refmeta>
  41                 <refentrytitle>systemd.special</refentrytitle>
  42                 <manvolnum>7</manvolnum>
  43         </refmeta>
  44
  45         <refnamediv>
  46                 <refname>systemd.special</refname>
  47                 <refpurpose>Special systemd units</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename>basic.target</filename>,
  52                 <filename>ctrl-alt-del.target</filename>,
  53                 <filename>dbus.service</filename>,
  54                 <filename>dbus.socket</filename>,
  55                 <filename>default.target</filename>,
  56                 <filename>display-manager.service</filename>,
  57                 <filename>emergency.target</filename>,
  58                 <filename>exit.service</filename>,
  59                 <filename>final.service</filename>,
  60                 <filename>graphical.target</filename>,
  61                 <filename>http-daemon.target</filename>,
  62                 <filename>halt.target</filename>,
  63                 <filename>kbrequest.target</filename>,
  64                 <filename>kexec.target</filename>,
  65                 <filename>local-fs.target</filename>,
  66                 <filename>local-fs-pre.target</filename>,
  67                 <filename>mail-transfer-agent.target</filename>,
  68                 <filename>multi-user.target</filename>,
  69                 <filename>network.target</filename>,
  70                 <filename>nss-lookup.target</filename>,
  71                 <filename>poweroff.target</filename>,
  72                 <filename>reboot.target</filename>,
  73                 <filename>remote-fs.target</filename>,
  74                 <filename>remote-fs-pre.target</filename>,
  75                 <filename>rescue.target</filename>,
  76                 <filename>rpcbind.target</filename>,
  77                 <filename>runlevel2.target</filename>,
  78                 <filename>runlevel3.target</filename>,
  79                 <filename>runlevel4.target</filename>,
  80                 <filename>runlevel5.target</filename>,
  81                 <filename>shutdown.target</filename>,
  82                 <filename>sigpwr.target</filename>,
  83                 <filename>sockets.target</filename>,
  84                 <filename>swap.target</filename>,
  85                 <filename>sysinit.target</filename>,
  86                 <filename>syslog.service</filename>,
  87                 <filename>syslog.socket</filename>,
  88                 <filename>syslog.target</filename>,
  89                 <filename>time-sync.target</filename>,
  90                 <filename>umount.target</filename></para>
  91         </refsynopsisdiv>
  92
  93         <refsect1>
  94                 <title>Description</title>
  95
  96                 <para>A few units are treated specially by
  97                 systemd. They have special internal semantics and
  98                 cannot be renamed.</para>
  99         </refsect1>
 100
 101         <refsect1>
 102                 <title>Special System Units</title>
 103
 104                 <variablelist>
 105                         <varlistentry>
 106                                 <term><filename>basic.target</filename></term>
 107                                 <listitem>
 108                                         <para>A special target unit
 109                                         covering early boot-up.</para>
 110                                         <para>systemd automatically
 111                                         adds dependencies of the types
 112                                         Requires and After for this
 113                                         target unit to all SysV
 114                                         service units configured for
 115                                         runlevel 1 to 5.</para>
 116                                         <para>Usually this should pull-in
 117                                         all sockets, mount points,
 118                                         swap devices and other basic
 119                                         initialization necessary for
 120                                         the general purpose
 121                                         daemons. Most normal daemons
 122                                         should have dependencies of
 123                                         type After and Requires on
 124                                         this unit.</para>
 125                                 </listitem>
 126                         </varlistentry>
 127                         <varlistentry>
 128                                 <term><filename>ctrl-alt-del.target</filename></term>
 129                                 <listitem>
 130                                         <para>systemd starts this
 131                                         target whenever
 132                                         Control+Alt+Del is pressed on
 133                                         the console. Usually this
 134                                         should be aliased (symlinked)
 135                                         to
 136                                         <filename>reboot.target</filename>.</para>
 137                                 </listitem>
 138                         </varlistentry>
 139                         <varlistentry>
 140                                 <term><filename>dbus.service</filename></term>
 141                                 <listitem>
 142                                         <para>A special unit for the
 143                                         D-Bus system bus. As soon as
 144                                         this service is fully started
 145                                         up systemd will connect to it
 146                                         and register its
 147                                         service.</para>
 148                                 </listitem>
 149                         </varlistentry>
 150                         <varlistentry>
 151                                 <term><filename>dbus.socket</filename></term>
 152                                 <listitem>
 153                                         <para>A special unit for the
 154                                         D-Bus system bus socket. All
 155                                         units with
 156                                         <literal>Type=dbus</literal>
 157                                         automatically gain a
 158                                         dependency on this
 159                                         unit.</para>
 160                                 </listitem>
 161                         </varlistentry>
 162                         <varlistentry>
 163                                 <term><filename>default.target</filename></term>
 164                                 <listitem>
 165                                         <para>The default unit systemd
 166                                         starts at bootup. Usually this
 167                                         should be aliased (symlinked)
 168                                         to
 169                                         <filename>multi-user.target</filename>
 170                                         or
 171                                         <filename>graphical.target</filename>.</para>
 172                                         <para>The default unit systemd
 173                                         starts at bootup can be
 174                                         overridden with the
 175                                         <varname>systemd.unit=</varname>
 176                                         kernel command line option.</para>
 177                                 </listitem>
 178                         </varlistentry>
 179                         <varlistentry>
 180                                 <term><filename>display-manager.service</filename></term>
 181                                 <listitem>
 182                                         <para>The display manager
 183                                         service. Usually this should
 184                                         be aliased (symlinked) to
 185                                         <filename>gdm.service</filename>
 186                                         or a similar display manager
 187                                         service.</para>
 188                                         <para>systemd automatically
 189                                         adds dependencies of type
 190                                         After for this target unit to
 191                                         all SysV init script service
 192                                         units with a LSB header
 193                                         referring to the
 194                                         <literal>$x-display-manager</literal>
 195                                         facility, for compatibility
 196                                         with Debian.</para>
 197                                 </listitem>
 198                         </varlistentry>
 199                         <varlistentry>
 200                                 <term><filename>emergency.target</filename></term>
 201                                 <listitem>
 202                                         <para>A special target unit
 203                                         that starts an emergency
 204                                         shell on the main
 205                                         console. This unit is supposed
 206                                         to be used with the kernel
 207                                         command line option
 208                                         <varname>systemd.unit=</varname>
 209                                         and has otherwise little use.
 210                                         </para>
 211                                 </listitem>
 212                         </varlistentry>
 213                         <varlistentry>
 214                                 <term><filename>final.target</filename></term>
 215                                 <listitem>
 216                                         <para>A special target unit
 217                                         that is used during the
 218                                         shutdown logic and may be used
 219                                         to pull in late services after
 220                                         all normal services are
 221                                         already terminated and all
 222                                         mounts unmounted.
 223                                         </para>
 224                                 </listitem>
 225                         </varlistentry>
 226                         <varlistentry>
 227                                 <term><filename>graphical.target</filename></term>
 228                                 <listitem>
 229                                         <para>A special target unit
 230                                         for setting up a graphical
 231                                         login screen. This pulls in
 232                                         <filename>multi-user.target</filename>.</para>
 233
 234                                         <para>Units that are needed
 235                                         for graphical login shall add
 236                                         Wants dependencies for their
 237                                         unit to this unit (or
 238                                         <filename>multi-user.target</filename>)
 239                                         during installation.</para>
 240                                 </listitem>
 241                         </varlistentry>
 242                         <varlistentry>
 243                                 <term><filename>http-daemon.target</filename></term>
 244                                 <listitem>
 245                                         <para>A target for pulling in
 246                                         an HTTP server if there is
 247                                         any.</para>
 248                                         <para>systemd automatically
 249                                         adds dependencies of type
 250                                         After for this target unit to
 251                                         all SysV init script service
 252                                         units with a LSB header
 253                                         referring to the
 254                                         <literal>$httpd</literal>
 255                                         facility.</para>
 256                                 </listitem>
 257                         </varlistentry>
 258                         <varlistentry>
 259                                 <term><filename>halt.target</filename></term>
 260                                 <listitem>
 261                                         <para>A special target unit
 262                                         for shutting down and halting the system.</para>
 263
 264                                         <para>Applications wanting to
 265                                         halt the system should start
 266                                         this unit.</para>
 267                                 </listitem>
 268                         </varlistentry>
 269                         <varlistentry>
 270                                 <term><filename>kbrequest.target</filename></term>
 271                                 <listitem>
 272                                         <para>systemd starts this
 273                                         target whenever Alt+ArrowUp is
 274                                         pressed on the console. This
 275                                         is a good candidate to be
 276                                         aliased (symlinked) to
 277                                         <filename>rescue.target</filename>.</para>
 278                                 </listitem>
 279                         </varlistentry>
 280                         <varlistentry>
 281                                 <term><filename>kexec.target</filename></term>
 282                                 <listitem>
 283                                         <para>A special target unit
 284                                         for shutting down and rebooting the system via kexec.</para>
 285
 286                                         <para>Applications wanting to
 287                                         reboot the system with kexec should start
 288                                         this unit.</para>
 289                                 </listitem>
 290                         </varlistentry>
 291                         <varlistentry>
 292                                 <term><filename>local-fs.target</filename></term>
 293                                 <listitem>
 294                                         <para>systemd automatically
 295                                         adds dependencies of type
 296                                         After to all mount units that
 297                                         refer to local mount points
 298                                         for this target unit. In
 299                                         addition, systemd adds
 300                                         dependencies of type Wants to
 301                                         this target unit for those
 302                                         mounts listed in
 303                                         <filename>/etc/fstab</filename>
 304                                         that have the
 305                                         <option>auto</option> and
 306                                         <option>comment=systemd.mount</option>
 307                                         mount options set.</para>
 308
 309                                         <para>systemd automatically
 310                                         adds dependencies of type
 311                                         After for this target unit to
 312                                         all SysV init script service
 313                                         units with an LSB header
 314                                         referring to the
 315                                         <literal>$local_fs</literal>
 316                                         facility.</para>
 317                                 </listitem>
 318                         </varlistentry>
 319                         <varlistentry>
 320                                 <term><filename>local-fs-pre.target</filename></term>
 321                                 <listitem>
 322                                         <para>This target unit is
 323                                         automatically ordered before
 324                                         all local mount points marked
 325                                         with <option>auto</option>
 326                                         (see above). It can be used to
 327                                         execute certain units before
 328                                         all local mounts.</para>
 329                                 </listitem>
 330                         </varlistentry>
 331                         <varlistentry>
 332                                 <term><filename>mail-transfer-agent.target</filename></term>
 333                                 <listitem>
 334                                         <para>The mail transfer agent
 335                                         (MTA) service. Usually this
 336                                         should pull-in all units
 337                                         necessary for
 338                                         sending/receiving mails on the
 339                                         local host.</para>
 340
 341                                         <para>systemd automatically
 342                                         adds dependencies of type
 343                                         After for this target unit to
 344                                         all SysV init script service
 345                                         units with an LSB header
 346                                         referring to the
 347                                         <literal>$mail-transfer-agent</literal>
 348                                         or
 349                                         <literal>$mail-transport-agent</literal>
 350                                         facilities, for compatibility
 351                                         with Debian.</para>
 352                                 </listitem>
 353                         </varlistentry>
 354                         <varlistentry>
 355                                 <term><filename>multi-user.target</filename></term>
 356                                 <listitem>
 357                                         <para>A special target unit
 358                                         for setting up a multi-user
 359                                         system (non-graphical). This
 360                                         is pulled in by
 361                                         <filename>graphical.target</filename>.</para>
 362
 363                                         <para>Units that are needed
 364                                         for a multi-user system shall
 365                                         add Wants dependencies to
 366                                         this unit for their unit during
 367                                         installation.</para>
 368                                 </listitem>
 369                         </varlistentry>
 370                         <varlistentry>
 371                                 <term><filename>network.target</filename></term>
 372                                 <listitem>
 373                                         <para>systemd automatically
 374                                         adds dependencies of type
 375                                         After for this target unit to
 376                                         all SysV init script service
 377                                         units with an LSB header
 378                                         referring to the
 379                                         <literal>$network</literal>
 380                                         facility.</para>
 381                                 </listitem>
 382                         </varlistentry>
 383                         <varlistentry>
 384                                 <term><filename>nss-lookup.target</filename></term>
 385                                 <listitem>
 386                                         <para>A target that should be
 387                                         used as synchronization point
 388                                         for all host/network name
 389                                         service lookups. Note that
 390                                         this is independent of
 391                                         user/group name lookups for
 392                                         which
 393                                         <filename>nss-user-lookup.target</filename>
 394                                         should be used. systemd
 395                                         automatically adds
 396                                         dependencies of type After for
 397                                         this target unit to all SysV
 398                                         init script service units with
 399                                         an LSB header referring to the
 400                                         <literal>$named</literal>
 401                                         facility.</para>
 402                                 </listitem>
 403                         </varlistentry>
 404                         <varlistentry>
 405                                 <term><filename>nss-user-lookup.target</filename></term>
 406                                 <listitem>
 407                                         <para>A target that should be
 408                                         used as synchronization point
 409                                         for all user/group name
 410                                         service lookups. Note that
 411                                         this is independent of
 412                                         host/network name lookups for
 413                                         which
 414                                         <filename>nss-lookup.target</filename>
 415                                         should be used. </para>
 416                                 </listitem>
 417                         </varlistentry>
 418                         <varlistentry>
 419                                 <term><filename>poweroff.target</filename></term>
 420                                 <listitem>
 421                                         <para>A special target unit
 422                                         for shutting down and powering off the system.</para>
 423
 424                                         <para>Applications wanting to
 425                                         power off the system should start
 426                                         this unit.</para>
 427
 428                                         <para><filename>runlevel0.target</filename>
 429                                         is an alias for this target
 430                                         unit, for compatibility with SysV.</para>
 431                                 </listitem>
 432                         </varlistentry>
 433                         <varlistentry>
 434                                 <term><filename>reboot.target</filename></term>
 435                                 <listitem>
 436                                         <para>A special target unit
 437                                         for shutting down and rebooting the system.</para>
 438
 439                                         <para>Applications wanting to
 440                                         reboot the system should start
 441                                         this unit.</para>
 442
 443                                         <para><filename>runlevel6.target</filename>
 444                                         is an alias for this target
 445                                         unit, for compatibility with SysV.</para>
 446                                 </listitem>
 447                         </varlistentry>
 448                         <varlistentry>
 449                                 <term><filename>remote-fs.target</filename></term>
 450                                 <listitem>
 451                                         <para>Similar to
 452                                         <filename>local-fs.target</filename>,
 453                                         but for remote mount
 454                                         points.</para>
 455
 456                                         <para>systemd automatically
 457                                         adds dependencies of type
 458                                         After for this target unit to
 459                                         all SysV init script service
 460                                         units with an LSB header
 461                                         referring to the
 462                                         <literal>$remote_fs</literal>
 463                                         facility.</para>
 464                                 </listitem>
 465                         </varlistentry>
 466                         <varlistentry>
 467                                 <term><filename>remote-fs-pre.target</filename></term>
 468                                 <listitem>
 469                                         <para>This target unit is
 470                                         automatically ordered before
 471                                         all remote mount points marked
 472                                         with <option>auto</option>
 473                                         (see above). It can be used to
 474                                         execute certain units before
 475                                         all remote mounts.</para>
 476                                 </listitem>
 477                         </varlistentry>
 478                         <varlistentry>
 479                                 <term><filename>rescue.target</filename></term>
 480                                 <listitem>
 481                                         <para>A special target unit
 482                                         for setting up the base system
 483                                         and a rescue shell.</para>
 484
 485                                         <para><filename>runlevel1.target</filename>
 486                                         is an alias for this target
 487                                         unit, for compatibility with SysV.</para>
 488                                 </listitem>
 489                         </varlistentry>
 490                         <varlistentry>
 491                                 <term><filename>rpcbind.target</filename></term>
 492                                 <listitem>
 493                                         <para>systemd automatically
 494                                         adds dependencies of type
 495                                         After for this target unit to
 496                                         all SysV init script service
 497                                         units with an LSB header
 498                                         referring to the
 499                                         <literal>$rpcbind</literal>
 500                                         facility.</para>
 501                                 </listitem>
 502                         </varlistentry>
 503                         <varlistentry>
 504                                 <term><filename>runlevel2.target</filename></term>
 505                                 <listitem>
 506                                         <para>This is a target that is
 507                                         called whenever the SysV
 508                                         compatibility code asks for
 509                                         runlevel 2. It is a good idea
 510                                         to make this an alias for
 511                                         (i.e. symlink to)
 512                                         <filename>multi-user.target</filename>.</para>
 513                                 </listitem>
 514                         </varlistentry>
 515                         <varlistentry>
 516                                 <term><filename>runlevel3.target</filename></term>
 517                                 <listitem>
 518                                         <para>This is a target that is
 519                                         called whenever the SysV
 520                                         compatibility code asks for
 521                                         runlevel 3. It is a good idea
 522                                         to make this an alias for
 523                                         (i.e. symlink to)
 524                                         <filename>multi-user.target</filename>
 525                                         or
 526                                         <filename>graphical.target</filename>.</para>
 527                                 </listitem>
 528                         </varlistentry>
 529                         <varlistentry>
 530                                 <term><filename>runlevel4.target</filename></term>
 531                                 <listitem>
 532                                         <para>This is a target that is
 533                                         called whenever the SysV
 534                                         compatibility code asks for
 535                                         runlevel 4. It is a good idea
 536                                         to make this an alias for
 537                                         (i.e. symlink to)
 538                                         <filename>multi-user.target</filename>
 539                                         or
 540                                         <filename>graphical.target</filename>.</para>
 541                                 </listitem>
 542                         </varlistentry>
 543                         <varlistentry>
 544                                 <term><filename>runlevel5.target</filename></term>
 545                                 <listitem>
 546                                         <para>This is a target that is
 547                                         called whenever the SysV
 548                                         compatibility code asks for
 549                                         runlevel 5. It is a good idea
 550                                         to make this an alias for
 551                                         (i.e. symlink to)
 552                                         <filename>multi-user.target</filename>
 553                                         or
 554                                         <filename>graphical.target</filename>.</para>
 555                                 </listitem>
 556                         </varlistentry>
 557                         <varlistentry>
 558                                 <term><filename>shutdown.target</filename></term>
 559                                 <listitem>
 560                                         <para>A special target unit
 561                                         that terminates the services
 562                                         on system shutdown.</para>
 563
 564                                         <para>Services that shall be
 565                                         terminated on system shutdown
 566                                         shall add Conflicts
 567                                         dependencies to this unit for
 568                                         their service unit, which is
 569                                         implicitly done when
 570                                         <varname>DefaultDependencies=yes</varname>
 571                                         is set (the default).</para>
 572
 573                                         <para>systemd automatically
 574                                         adds dependencies of type
 575                                         Conflicts to this target unit
 576                                         for all SysV init script
 577                                         service units that shall be
 578                                         terminated in SysV runlevels 0
 579                                         or 6.</para>
 580                                 </listitem>
 581                         </varlistentry>
 582                         <varlistentry>
 583                                 <term><filename>sigpwr.target</filename></term>
 584                                 <listitem>
 585                                         <para>A special target that is
 586                                         started when systemd receives
 587                                         the SIGPWR process signal,
 588                                         which is normally sent by the
 589                                         kernel or UPS daemons when
 590                                         power fails.</para>
 591                                 </listitem>
 592                         </varlistentry>
 593                         <varlistentry>
 594                                 <term><filename>sockets.target</filename></term>
 595                                 <listitem>
 596                                         <para>A special target unit
 597                                         that sets up all service
 598                                         sockets.</para>
 599
 600                                         <para>Services that can be
 601                                         socket-activated shall add
 602                                         Wants dependencies to this
 603                                         unit for their socket unit
 604                                         during installation.</para>
 605                                 </listitem>
 606                         </varlistentry>
 607                         <varlistentry>
 608                                 <term><filename>swap.target</filename></term>
 609                                 <listitem>
 610                                         <para>Similar to
 611                                         <filename>local-fs.target</filename>, but for swap
 612                                         partitions and swap
 613                                         files.</para>
 614                                 </listitem>
 615                         </varlistentry>
 616                         <varlistentry>
 617                                 <term><filename>sysinit.target</filename></term>
 618                                 <listitem>
 619                                         <para>A special target unit
 620                                         covering early boot-up scripts.</para>
 621                                         <para>systemd automatically
 622                                         adds dependencies of the types
 623                                         Wants and After for all
 624                                         SysV service units configured
 625                                         for runlevels that are not 0
 626                                         to 6 to this target unit.
 627                                         This covers the special
 628                                         boot-up runlevels some
 629                                         distributions have, such as S
 630                                         or b.</para>
 631                                 </listitem>
 632                         </varlistentry>
 633                         <varlistentry>
 634                                 <term><filename>syslog.service</filename></term>
 635                                 <listitem>
 636                                         <para>The syslog service if
 637                                         any. Implementations should
 638                                         create a symlink from the
 639                                         actual syslog implementation
 640                                         to this generic name for
 641                                         activating it.</para>
 642                                 </listitem>
 643                         </varlistentry>
 644                         <varlistentry>
 645                                 <term><filename>syslog.socket</filename></term>
 646                                 <listitem>
 647                                         <para>The socket unit where
 648                                         syslog implementations should
 649                                         listen on. All userspace log
 650                                         messages will be made
 651                                         available on this
 652                                         socket.</para>
 653                                 </listitem>
 654                         </varlistentry>
 655                         <varlistentry>
 656                                 <term><filename>syslog.target</filename></term>
 657                                 <listitem>
 658                                         <para>systemd automatically
 659                                         adds dependencies of type
 660                                         After for this target unit to
 661                                         all SysV init script service
 662                                         units with an LSB header
 663                                         referring to the
 664                                         <literal>$syslog</literal>
 665                                         facility.</para>
 666                                 </listitem>
 667                         </varlistentry>
 668                         <varlistentry>
 669                                 <term><filename>time-sync.target</filename></term>
 670                                 <listitem>
 671                                         <para>systemd automatically
 672                                         adds dependencies of type
 673                                         After for this target unit to
 674                                         all SysV init script service
 675                                         units with an LSB header
 676                                         referring to the
 677                                         <literal>$time</literal>
 678                                         facility.</para>
 679                                 </listitem>
 680                         </varlistentry>
 681                         <varlistentry>
 682                                 <term><filename>umount.target</filename></term>
 683                                 <listitem>
 684                                         <para>A special target unit
 685                                         that umounts all mount and
 686                                         automount points on system
 687                                         shutdown.</para>
 688
 689                                         <para>Mounts that shall be
 690                                         unmounted on system shutdown
 691                                         shall add Conflicts
 692                                         dependencies to this unit for
 693                                         their mount unit, which is
 694                                         implicitly done when
 695                                         <varname>DefaultDependencies=yes</varname>
 696                                         is set (the default).</para>
 697                                 </listitem>
 698                         </varlistentry>
 699                 </variablelist>
 700         </refsect1>
 701
 702         <refsect1>
 703                 <title>Special User Units</title>
 704
 705                 <para>When systemd runs as a user instance, the
 706                 following special units are available, which have
 707                 similar definitions as their system counterparts:
 708                 <filename>default.target</filename>,
 709                 <filename>shutdown.target</filename>,
 710                 <filename>sockets.target</filename></para>
 711
 712                 <para>In addition the following special unit is
 713                 understood only when systemd runs as service instance:</para>
 714
 715                 <variablelist>
 716                         <varlistentry>
 717                                 <term><filename>exit.service</filename></term>
 718                                 <listitem>
 719                                         <para>A special service unit
 720                                         for shutting down the
 721                                         user service manager.</para>
 722
 723                                         <para>Applications wanting to
 724                                         terminate the user service
 725                                         manager should start this
 726                                         unit. If systemd receives
 727                                         SIGTERM or SIGINT when running
 728                                         as user service daemon it will
 729                                         start this unit.</para>
 730
 731                                         <para>Normally, this pulls in
 732                                         <filename>shutdown.target</filename>
 733                                         which in turn should be
 734                                         conflicted by all units that
 735                                         want to be shut down on
 736                                         user service manager exit.</para>
 737                                 </listitem>
 738                         </varlistentry>
 739                 </variablelist>
 740         </refsect1>
 741
 742         <refsect1>
 743                   <title>See Also</title>
 744                   <para>
 745                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 746                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 747                           <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 748                           <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 749                           <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 750                   </para>
 751         </refsect1>
 752
 753 </refentry>