1SYSTEMD.SPECIAL(7) systemd.special SYSTEMD.SPECIAL(7)
2
6 systemd.special - Special systemd units
7
9 basic.target, bluetooth.target, cryptsetup-pre.target,
10 cryptsetup.target, ctrl-alt-del.target, blockdev@.target,
11 boot-complete.target, default.target, emergency.target, exit.target,
12 final.target, getty.target, getty-pre.target, graphical.target,
13 halt.target, hibernate.target, hybrid-sleep.target,
14 suspend-then-hibernate.target, initrd.target, initrd-fs.target,
15 initrd-root-device.target, initrd-root-fs.target, kbrequest.target,
16 kexec.target, local-fs-pre.target, local-fs.target, machines.target
17 multi-user.target, network-online.target, network-pre.target,
18 network.target, nss-lookup.target, nss-user-lookup.target,
19 paths.target, poweroff.target, printer.target, reboot.target,
20 remote-cryptsetup.target, remote-fs-pre.target, remote-fs.target,
21 rescue.target, rpcbind.target, runlevel2.target, runlevel3.target,
22 runlevel4.target, runlevel5.target, shutdown.target, sigpwr.target,
23 sleep.target, slices.target, smartcard.target, sockets.target,
24 sound.target, suspend.target, swap.target, sysinit.target,
25 system-update.target, system-update-pre.target, time-set.target,
26 time-sync.target, timers.target, umount.target, usb-gadget.target,
27 -.slice, system.slice, user.slice, machine.slice, -.mount,
28 dbus.service, dbus.socket, display-manager.service, init.scope,
29 syslog.socket, system-update-cleanup.service
30
32 A few units are treated specially by systemd. Many of them have special
33 internal semantics and cannot be renamed, while others simply have a
34 standard meaning and should be present on all systems.
35
37 Special System Units
38 -.mount
39 The root mount point, i.e. the mount unit for the / path. This unit
40 is unconditionally active, during the entire time the system is up,
41 as this mount point is where the basic userspace is running from.
42 basic.target
44 A special target unit covering basic boot-up.
45 systemd automatically adds dependency of the type After= for this
47 target unit to all services (except for those with
48 DefaultDependencies=no).
49 Usually, this should pull-in all local mount points plus /var, /tmp
51 and /var/tmp, swap devices, sockets, timers, path units and other
52 basic initialization necessary for general purpose daemons. The
53 mentioned mount points are special cased to allow them to be
54 remote.
55 This target usually does not pull in any non-target units directly,
57 but rather does so indirectly via other early boot targets. It is
58 instead meant as a synchronization point for late boot services.
59 Refer to bootup(7) for details on the targets involved.
60 boot-complete.target
62 This target is intended as generic synchronization point for
63 services that shall determine or act on whether the boot process
64 completed successfully. Order units that are required to succeed
65 for a boot process to be considered successful before this unit,
66 and add a Requires= dependency from the target unit to them. Order
67 units that shall only run when the boot process is considered
68 successful after the target unit and pull in the target from it,
69 also with Requires=. Note that by default this target unit is not
70 part of the initial boot transaction, but is supposed to be pulled
71 in only if required by units that want to run only on successful
72 boots.
73 See systemd-boot-check-no-failures.service(8) for a service that
75 implements a generic system health check and orders itself before
76 boot-complete.target.
77 See systemd-bless-boot.service(8) for a service that propagates
79 boot success information to the boot loader, and orders itself
80 after boot-complete.target.
81 ctrl-alt-del.target
83 systemd starts this target whenever Control+Alt+Del is pressed on
84 the console. Usually, this should be aliased (symlinked) to
85 reboot.target.
86 cryptsetup.target
88 A target that pulls in setup services for all encrypted block
89 devices.
90 dbus.service
92 A special unit for the D-Bus bus daemon. As soon as this service is
93 fully started up systemd will connect to it and register its
94 service.
95 dbus.socket
97 A special unit for the D-Bus system bus socket. All units with
98 Type=dbus automatically gain a dependency on this unit.
99 default.target
101 The default unit systemd starts at bootup. Usually, this should be
102 aliased (symlinked) to multi-user.target or graphical.target. See
103 bootup(7) for more discussion.
104 The default unit systemd starts at bootup can be overridden with
106 the systemd.unit= kernel command line option, or more conveniently,
107 with the short names like single, rescue, 1, 3, 5, ...; see
108 systemd(1).
109 display-manager.service
111 The display manager service. Usually, this should be aliased
112 (symlinked) to gdm.service or a similar display manager service.
113 emergency.target
115 A special target unit that starts an emergency shell on the main
116 console. This target does not pull in any services or mounts. It is
117 the most minimal version of starting the system in order to acquire
118 an interactive shell; the only processes running are usually just
119 the system manager (PID 1) and the shell process. This unit is
120 supposed to be used with the kernel command line option
121 systemd.unit=; it is also used when a file system check on a
122 required file system fails, and boot-up cannot continue. Compare
123 with rescue.target, which serves a similar purpose, but also starts
124 the most basic services and mounts all file systems.
125 Use the "systemd.unit=emergency.target" kernel command line option
127 to boot into this mode. A short alias for this kernel command line
128 option is "emergency", for compatibility with SysV.
129 In many ways booting into emergency.target is similar to the effect
131 of booting with "init=/bin/sh" on the kernel command line, except
132 that emergency mode provides you with the full system and service
133 manager, and allows starting individual units in order to continue
134 the boot process in steps.
135 exit.target
137 A special service unit for shutting down the system or user service
138 manager. It is equivalent to poweroff.target on non-container
139 systems, and also works in containers.
140 systemd will start this unit when it receives the SIGTERM or SIGINT
142 signal when running as user service daemon.
143 Normally, this (indirectly) pulls in shutdown.target, which in turn
145 should be conflicted by all units that want to be scheduled for
146 shutdown when the service manager starts to exit.
147 final.target
149 A special target unit that is used during the shutdown logic and
150 may be used to pull in late services after all normal services are
151 already terminated and all mounts unmounted.
152 getty.target
154 A special target unit that pulls in statically configured local TTY
155 getty instances.
156 graphical.target
158 A special target unit for setting up a graphical login screen. This
159 pulls in multi-user.target.
160 Units that are needed for graphical logins shall add Wants=
162 dependencies for their unit to this unit (or multi-user.target)
163 during installation. This is best configured via
164 WantedBy=graphical.target in the unit's "[Install]" section.
165 hibernate.target
167 A special target unit for hibernating the system. This pulls in
168 sleep.target.
169 hybrid-sleep.target
171 A special target unit for hibernating and suspending the system at
172 the same time. This pulls in sleep.target.
173 suspend-then-hibernate.target
175 A special target unit for suspending the system for a period of
176 time, waking it and putting it into hibernate. This pulls in
177 sleep.target.
178 halt.target
180 A special target unit for shutting down and halting the system.
181 Note that this target is distinct from poweroff.target in that it
182 generally really just halts the system rather than powering it
183 down.
184 Applications wanting to halt the system should not start this unit
186 directly, but should instead execute systemctl halt (possibly with
187 the --no-block option) or call systemd(1)'s
188 org.freedesktop.systemd1.Manager.Halt D-Bus method directly.
189 init.scope
191 This scope unit is where the system and service manager (PID 1)
192 itself resides. It is active as long as the system is running.
193 initrd.target
195 This is the default target in the initramfs, similar to
196 default.target in the main system. It is used to mount the real
197 root and transition to it. See bootup(7) for more discussion.
198 initrd-fs.target
200 systemd-fstab-generator(3) automatically adds dependencies of type
201 Before= to sysroot-usr.mount and all mount points found in
202 /etc/fstab that have x-initrd.mount and not have noauto mount
203 options set.
204 initrd-root-device.target
206 A special initrd target unit that is reached when the root
207 filesystem device is available, but before it has been mounted.
208 systemd-fstab-generator(3) and systemd-gpt-auto-generator(3)
209 automatically setup the appropriate dependencies to make this
210 happen.
211 initrd-root-fs.target
213 systemd-fstab-generator(3) automatically adds dependencies of type
214 Before= to the sysroot.mount unit, which is generated from the
215 kernel command line.
216 kbrequest.target
218 systemd starts this target whenever Alt+ArrowUp is pressed on the
219 console. Note that any user with physical access to the machine
220 will be able to do this, without authentication, so this should be
221 used carefully.
222 kexec.target
224 A special target unit for shutting down and rebooting the system
225 via kexec.
226 Applications wanting to reboot the system should not start this
228 unit directly, but should instead execute systemctl kexec (possibly
229 with the --no-block option) or call systemd(1)'s
230 org.freedesktop.systemd1.Manager.KExec D-Bus method directly.
231 local-fs.target
233 systemd-fstab-generator(3) automatically adds dependencies of type
234 Before= to all mount units that refer to local mount points for
235 this target unit. In addition, it adds dependencies of type Wants=
236 to this target unit for those mounts listed in /etc/fstab that have
237 the auto mount option set.
238 machines.target
240 A standard target unit for starting all the containers and other
241 virtual machines. See systemd-nspawn@.service for an example.
242 multi-user.target
244 A special target unit for setting up a multi-user system
245 (non-graphical). This is pulled in by graphical.target.
246 Units that are needed for a multi-user system shall add Wants=
248 dependencies for their unit to this unit during installation. This
249 is best configured via WantedBy=multi-user.target in the unit's
250 "[Install]" section.
251 network-online.target
253 Units that strictly require a configured network connection should
254 pull in network-online.target (via a Wants= type dependency) and
255 order themselves after it. This target unit is intended to pull in
256 a service that delays further execution until the network is
257 sufficiently set up. What precisely this requires is left to the
258 implementation of the network managing service.
259 Note the distinction between this unit and network.target. This
261 unit is an active unit (i.e. pulled in by the consumer rather than
262 the provider of this functionality) and pulls in a service which
263 possibly adds substantial delays to further execution. In contrast,
264 network.target is a passive unit (i.e. pulled in by the provider of
265 the functionality, rather than the consumer) that usually does not
266 delay execution much. Usually, network.target is part of the boot
267 of most systems, while network-online.target is not, except when at
268 least one unit requires it. Also see Running Services After the
269 Network is up[1] for more information.
270 All mount units for remote network file systems automatically pull
272 in this unit, and order themselves after it. Note that networking
273 daemons that simply provide functionality to other hosts generally
274 do not need to pull this in.
275 systemd automatically adds dependencies of type Wants= and After=
277 for this target unit to all SysV init script service units with an
278 LSB header referring to the "$network" facility.
279 Note that this unit is only useful during the original system
281 start-up logic. After the system has completed booting up, it will
282 not track the online state of the system anymore. Due to this it
283 cannot be used as a network connection monitor concept, it is
284 purely a one-time system start-up concept.
285 paths.target
287 A special target unit that sets up all path units (see
288 systemd.path(5) for details) that shall be active after boot.
289 It is recommended that path units installed by applications get
291 pulled in via Wants= dependencies from this unit. This is best
292 configured via a WantedBy=paths.target in the path unit's
293 "[Install]" section.
294 poweroff.target
296 A special target unit for shutting down and powering off the
297 system.
298 Applications wanting to power off the system should not start this
300 unit directly, but should instead execute systemctl poweroff
301 (possibly with the --no-block option) or call systemd-logind(8)'s
302 org.freedesktop.login1.Manager.PowerOff D-Bus method directly.
303 runlevel0.target is an alias for this target unit, for
305 compatibility with SysV.
306 reboot.target
308 A special target unit for shutting down and rebooting the system.
309 Applications wanting to reboot the system should not start this
311 unit directly, but should instead execute systemctl reboot
312 (possibly with the --no-block option) or call systemd-logind(8)'s
313 org.freedesktop.login1.Manager.Reboot D-Bus method directly.
314 runlevel6.target is an alias for this target unit, for
316 compatibility with SysV.
317 remote-cryptsetup.target
319 Similar to cryptsetup.target, but for encrypted devices which are
320 accessed over the network. It is used for crypttab(8) entries
321 marked with _netdev.
322 remote-fs.target
324 Similar to local-fs.target, but for remote mount points.
325 systemd automatically adds dependencies of type After= for this
327 target unit to all SysV init script service units with an LSB
328 header referring to the "$remote_fs" facility.
329 rescue.target
331 A special target unit that pulls in the base system (including
332 system mounts) and spawns a rescue shell. Isolate to this target in
333 order to administer the system in single-user mode with all file
334 systems mounted but with no services running, except for the most
335 basic. Compare with emergency.target, which is much more reduced
336 and does not provide the file systems or most basic services.
337 Compare with multi-user.target, this target could be seen as
338 single-user.target.
339 runlevel1.target is an alias for this target unit, for
341 compatibility with SysV.
342 Use the "systemd.unit=rescue.target" kernel command line option to
344 boot into this mode. A short alias for this kernel command line
345 option is "1", for compatibility with SysV.
346 runlevel2.target, runlevel3.target, runlevel4.target, runlevel5.target
348 These are targets that are called whenever the SysV compatibility
349 code asks for runlevel 2, 3, 4, 5, respectively. It is a good idea
350 to make this an alias for (i.e. symlink to) graphical.target (for
351 runlevel 5) or multi-user.target (the others).
352 shutdown.target
354 A special target unit that terminates the services on system
355 shutdown.
356 Services that shall be terminated on system shutdown shall add
358 Conflicts= and Before= dependencies to this unit for their service
359 unit, which is implicitly done when DefaultDependencies=yes is set
360 (the default).
361 sigpwr.target
363 A special target that is started when systemd receives the SIGPWR
364 process signal, which is normally sent by the kernel or UPS daemons
365 when power fails.
366 sleep.target
368 A special target unit that is pulled in by suspend.target,
369 hibernate.target and hybrid-sleep.target and may be used to hook
370 units into the sleep state logic.
371 slices.target
373 A special target unit that sets up all slice units (see
374 systemd.slice(5) for details) that shall always be active after
375 boot. By default the generic system.slice slice unit as well as the
376 root slice unit -.slice are pulled in and ordered before this unit
377 (see below).
378 Adding slice units to slices.target is generally not necessary.
380 Instead, when some unit that uses Slice= is started, the specified
381 slice will be started automatically. Adding WantedBy=slices.target
382 lines to the "[Install]" section should only be done for units that
383 need to be always active. In that case care needs to be taken to
384 avoid creating a loop through the automatic dependencies on
385 "parent" slices.
386 sockets.target
388 A special target unit that sets up all socket units (see
389 systemd.socket(5) for details) that shall be active after boot.
390 Services that can be socket-activated shall add Wants= dependencies
392 to this unit for their socket unit during installation. This is
393 best configured via a WantedBy=sockets.target in the socket unit's
394 "[Install]" section.
395 suspend.target
397 A special target unit for suspending the system. This pulls in
398 sleep.target.
399 swap.target
401 Similar to local-fs.target, but for swap partitions and swap files.
402 sysinit.target
404 systemd automatically adds dependencies of the types Requires= and
405 After= for this target unit to all services (except for those with
406 DefaultDependencies=no).
407 This target pulls in the services required for system
409 initialization. System services pulled in by this target should
410 declare DefaultDependencies=no and specify all their dependencies
411 manually, including access to anything more than a read only root
412 filesystem. For details on the dependencies of this target, refer
413 to bootup(7).
414 syslog.socket
416 The socket unit syslog implementations should listen on. All
417 userspace log messages will be made available on this socket. For
418 more information about syslog integration, please consult the
419 Syslog Interface[2] document.
420 system-update.target, system-update-pre.target,
422 system-update-cleanup.service
423 A special target unit that is used for offline system updates.
424 systemd-system-update-generator(8) will redirect the boot process
425 to this target if /system-update exists. For more information see
426 systemd.offline-updates(7).
427 Updates should happen before the system-update.target is reached,
429 and the services which implement them should cause the machine to
430 reboot. The main units executing the update should order themselves
431 after system-update-pre.target but not pull it in. Services which
432 want to run during system updates only, but before the actual
433 system update is executed should order themselves before this unit
434 and pull it in. As a safety measure, if this does not happen, and
435 /system-update still exists after system-update.target is reached,
436 system-update-cleanup.service will remove this symlink and reboot
437 the machine.
438 timers.target
440 A special target unit that sets up all timer units (see
441 systemd.timer(5) for details) that shall be active after boot.
442 It is recommended that timer units installed by applications get
444 pulled in via Wants= dependencies from this unit. This is best
445 configured via WantedBy=timers.target in the timer unit's
446 "[Install]" section.
447 umount.target
449 A special target unit that unmounts all mount and automount points
450 on system shutdown.
451 Mounts that shall be unmounted on system shutdown shall add
453 Conflicts dependencies to this unit for their mount unit, which is
454 implicitly done when DefaultDependencies=yes is set (the default).
455 Special System Units for Devices
457 Some target units are automatically pulled in as devices of certain
458 kinds show up in the system. These may be used to automatically
459 activate various services based on the specific type of the available
460 hardware.
461 bluetooth.target
463 This target is started automatically as soon as a Bluetooth
464 controller is plugged in or becomes available at boot.
465 This may be used to pull in Bluetooth management daemons
467 dynamically when Bluetooth hardware is found.
468 printer.target
470 This target is started automatically as soon as a printer is
471 plugged in or becomes available at boot.
472 This may be used to pull in printer management daemons dynamically
474 when printer hardware is found.
475 smartcard.target
477 This target is started automatically as soon as a smartcard
478 controller is plugged in or becomes available at boot.
479 This may be used to pull in smartcard management daemons
481 dynamically when smartcard hardware is found.
482 sound.target
484 This target is started automatically as soon as a sound card is
485 plugged in or becomes available at boot.
486 This may be used to pull in audio management daemons dynamically
488 when audio hardware is found.
489 usb-gadget.target
491 This target is started automatically as soon as a USB Device
492 Controller becomes available at boot.
493 This may be used to pull in usb gadget dynamically when UDC
495 hardware is found.
496 Special Passive System Units
498 A number of special system targets are defined that can be used to
499 properly order boot-up of optional services. These targets are
500 generally not part of the initial boot transaction, unless they are
501 explicitly pulled in by one of the implementing services. Note
502 specifically that these passive target units are generally not pulled
503 in by the consumer of a service, but by the provider of the service.
504 This means: a consuming service should order itself after these targets
505 (as appropriate), but not pull it in. A providing service should order
506 itself before these targets (as appropriate) and pull it in (via a
507 Wants= type dependency).
508 Note that these passive units cannot be started manually, i.e.
510 "systemctl start time-sync.target" will fail with an error. They can
511 only be pulled in by dependency. This is enforced since they exist for
512 ordering purposes only and thus are not useful as only unit within a
513 transaction.
514 blockdev@.target
516 This template unit is used to order mount units and other consumers
517 of block devices after services that synthesize these block
518 devices. In particular, this is intended to be used with storage
519 services (such as systemd-cryptsetup@.service(5)) that allocate and
520 manage a virtual block device. Storage services are ordered before
521 an instance of blockdev@.target, and the consumer units after it.
522 The ordering is particularly relevant during shutdown, as it
523 ensures that the mount is deactivated first and the service backing
524 the mount later. The blockdev@.target instance should be pulled in
525 via a Wants= dependency of the storage daemon and thus generally
526 not be part of any transaction unless a storage daemon is used. The
527 instance name for instances of this template unit must be a
528 properly escaped block device node path, e.g.
529 blockdev@dev-mapper-foobar.target for the storage device
530 /dev/mapper/foobar.
531 cryptsetup-pre.target
533 This passive target unit may be pulled in by services that want to
534 run before any encrypted block device is set up. All encrypted
535 block devices are set up after this target has been reached. Since
536 the shutdown order is implicitly the reverse start-up order between
537 units, this target is particularly useful to ensure that a service
538 is shut down only after all encrypted block devices are fully
539 stopped.
540 getty-pre.target
542 A special passive target unit. Users of this target are expected to
543 pull it in the boot transaction via a dependency (e.g. Wants=).
544 Order your unit before this unit if you want to make use of the
545 console just before getty is started.
546 local-fs-pre.target
548 This target unit is automatically ordered before all local mount
549 points marked with auto (see above). It can be used to execute
550 certain units before all local mounts.
551 network.target
553 This unit is supposed to indicate when network functionality is
554 available, but it is only very weakly defined what that is supposed
555 to mean, with one exception: at shutdown, a unit that is ordered
556 after network.target will be stopped before the network — to
557 whatever level it might be set up then — is shut down. It is hence
558 useful when writing service files that require network access on
559 shutdown, which should order themselves after this target, but not
560 pull it in. Also see Running Services After the Network is up[1]
561 for more information. Also see network-online.target described
562 above.
563 network-pre.target
565 This passive target unit may be pulled in by services that want to
566 run before any network is set up, for example for the purpose of
567 setting up a firewall. All network management software orders
568 itself after this target, but does not pull it in.
569 nss-lookup.target
571 A target that should be used as synchronization point for all
572 host/network name service lookups. Note that this is independent of
573 UNIX user/group name lookups for which nss-user-lookup.target
574 should be used. All services for which the availability of full
575 host/network name resolution is essential should be ordered after
576 this target, but not pull it in. systemd automatically adds
577 dependencies of type After= for this target unit to all SysV init
578 script service units with an LSB header referring to the "$named"
579 facility.
580 nss-user-lookup.target
582 A target that should be used as synchronization point for all
583 regular UNIX user/group name service lookups. Note that this is
584 independent of host/network name lookups for which
585 nss-lookup.target should be used. All services for which the
586 availability of the full user/group database is essential should be
587 ordered after this target, but not pull it in. All services which
588 provide parts of the user/group database should be ordered before
589 this target, and pull it in. Note that this unit is only relevant
590 for regular users and groups — system users and groups are required
591 to be resolvable during earliest boot already, and hence do not
592 need any special ordering against this target.
593 remote-fs-pre.target
595 This target unit is automatically ordered before all mount point
596 units (see above) and cryptsetup devices marked with the _netdev.
597 It can be used to run certain units before remote encrypted devices
598 and mounts are established. Note that this unit is generally not
599 part of the initial transaction, unless the unit that wants to be
600 ordered before all remote mounts pulls it in via a Wants= type
601 dependency. If the unit wants to be pulled in by the first remote
602 mount showing up, it should use network-online.target (see above).
603 rpcbind.target
605 The portmapper/rpcbind pulls in this target and orders itself
606 before it, to indicate its availability. systemd automatically adds
607 dependencies of type After= for this target unit to all SysV init
608 script service units with an LSB header referring to the "$portmap"
609 facility.
610 time-set.target
612 Services responsible for setting the system clock from a local
613 source (such as a maintained timestamp file or imprecise real-time
614 clock) should pull in this target and order themselves before it.
615 Services where approximate time is desired should be ordered after
616 this unit, but not pull it in. This target does not provide the
617 accuracy guarantees of time-sync.target.
618 time-sync.target
620 Services responsible for synchronizing the system clock from a
621 remote source (such as NTP client implementations) should pull in
622 this target and order themselves before it. All services where
623 correct time is essential should be ordered after this unit, but
624 not pull it in. systemd automatically adds dependencies of type
625 After= for this target unit to all SysV init script service units
626 with an LSB header referring to the "$time" facility.
627 Special Slice Units
629 There are four ".slice" units which form the basis of the hierarchy for
630 assignment of resources for services, users, and virtual machines or
631 containers. See systemd.slice(7) for details about slice units.
632 -.slice
634 The root slice is the root of the slice hierarchy. It usually does
635 not contain units directly, but may be used to set defaults for the
636 whole tree.
637 system.slice
639 By default, all system services started by systemd are found in
640 this slice.
641 user.slice
643 By default, all user processes and services started on behalf of
644 the user, including the per-user systemd instance are found in this
645 slice. This is pulled in by systemd-logind.service
646 machine.slice
648 By default, all virtual machines and containers registered with
649 systemd-machined are found in this slice. This is pulled in by
650 systemd-machined.service
651
653 Special User Units
654 When systemd runs as a user instance, the following special units are
655 available:
656 default.target
658 This is the main target of the user session, started by default.
659 Various services that compose the normal user session should be
660 pulled into this target. In this regard, default.target is similar
661 to multi-user.target in the system instance, but it is a real unit,
662 not an alias.
663 In addition, the following units are available which have definitions
665 similar to their system counterparts: exit.target, shutdown.target,
666 sockets.target, timers.target, paths.target, bluetooth.target,
667 printer.target, smartcard.target, sound.target.
668 Special Passive User Units
670 graphical-session.target
671 This target is active whenever any graphical session is running. It
672 is used to stop user services which only apply to a graphical (X,
673 Wayland, etc.) session when the session is terminated. Such
674 services should have "PartOf=graphical-session.target" in their
675 "[Unit]" section. A target for a particular session (e. g.
676 gnome-session.target) starts and stops "graphical-session.target"
677 with "BindsTo=graphical-session.target".
678 Which services are started by a session target is determined by the
680 "Wants=" and "Requires=" dependencies. For services that can be
681 enabled independently, symlinks in ".wants/" and ".requires/"
682 should be used, see systemd.unit(5). Those symlinks should either
683 be shipped in packages, or should be added dynamically after
684 installation, for example using "systemctl add-wants", see
685 systemctl(1).
686 Example 1. Nautilus as part of a GNOME session
688 "gnome-session.target" pulls in Nautilus as top-level service:
689 [Unit]
691 Description=User systemd services for GNOME graphical session
692 Wants=nautilus.service
693 BindsTo=graphical-session.target
694 "nautilus.service" gets stopped when the session stops:
696 [Unit]
698 Description=Render the desktop icons with Nautilus
699 PartOf=graphical-session.target
700 [Service]
702 ...
703 graphical-session-pre.target
705 This target contains services which set up the environment or
706 global configuration of a graphical session, such as SSH/GPG agents
707 (which need to export an environment variable into all desktop
708 processes) or migration of obsolete d-conf keys after an OS upgrade
709 (which needs to happen before starting any process that might use
710 them). This target must be started before starting a graphical
711 session like gnome-session.target.
712
714 systemd(1), systemd.unit(5), systemd.service(5), systemd.socket(5),
715 systemd.target(5), systemd.slice(5), bootup(7), systemd-fstab-
716 generator(8), user@.service(5)
717
719 1. Running Services After the Network is up
720 https://www.freedesktop.org/wiki/Software/systemd/NetworkTarget
721 2. Syslog Interface
723 https://www.freedesktop.org/wiki/Software/systemd/syslog
724systemd 245 SYSTEMD.SPECIAL(7)