1SYSTEMD.UNIT(5)                  systemd.unit                  SYSTEMD.UNIT(5)
2
3
4

NAME

6       systemd.unit - Unit configuration
7

SYNOPSIS

9       service.service, socket.socket, device.device, mount.mount,
10       automount.automount, swap.swap, target.target, path.path, timer.timer,
11       slice.slice, scope.scope
12
13   System Unit Search Path
14       /etc/systemd/system.control/*
15       /run/systemd/system.control/*
16       /run/systemd/transient/*
17       /run/systemd/generator.early/*
18       /etc/systemd/system/*
19       /etc/systemd/systemd.attached/*
20       /run/systemd/system/*
21       /run/systemd/systemd.attached/*
22       /run/systemd/generator/*
23       ...
24       /usr/lib/systemd/system/*
25       /run/systemd/generator.late/*
26
27   User Unit Search Path
28       ~/.config/systemd/user.control/*
29       $XDG_RUNTIME_DIR/systemd/user.control/*
30       $XDG_RUNTIME_DIR/systemd/transient/*
31       $XDG_RUNTIME_DIR/systemd/generator.early/*
32       ~/.config/systemd/user/*
33       /etc/systemd/user/*
34       $XDG_RUNTIME_DIR/systemd/user/*
35       /run/systemd/user/*
36       $XDG_RUNTIME_DIR/systemd/generator/*
37       ~/.local/share/systemd/user/*
38       ...
39       /usr/lib/systemd/user/*
40       $XDG_RUNTIME_DIR/systemd/generator.late/*
41

DESCRIPTION

43       A unit file is a plain text ini-style file that encodes information
44       about a service, a socket, a device, a mount point, an automount point,
45       a swap file or partition, a start-up target, a watched file system
46       path, a timer controlled and supervised by systemd(1), a resource
47       management slice or a group of externally created processes. See
48       systemd.syntax(5) for a general description of the syntax.
49
50       This man page lists the common configuration options of all the unit
51       types. These options need to be configured in the [Unit] or [Install]
52       sections of the unit files.
53
54       In addition to the generic [Unit] and [Install] sections described
55       here, each unit may have a type-specific section, e.g. [Service] for a
56       service unit. See the respective man pages for more information:
57       systemd.service(5), systemd.socket(5), systemd.device(5),
58       systemd.mount(5), systemd.automount(5), systemd.swap(5),
59       systemd.target(5), systemd.path(5), systemd.timer(5), systemd.slice(5),
60       systemd.scope(5).
61
62       Unit files are loaded from a set of paths determined during
63       compilation, described in the next section.
64
65       Valid unit names consist of a "name prefix" and a dot and a suffix
66       specifying the unit type. The "unit prefix" must consist of one or more
67       valid characters (ASCII letters, digits, ":", "-", "_", ".", and "\").
68       The total length of the unit name including the suffix must not exceed
69       256 characters. The type suffix must be one of ".service", ".socket",
70       ".device", ".mount", ".automount", ".swap", ".target", ".path",
71       ".timer", ".slice", or ".scope".
72
73       Units names can be parameterized by a single argument called the
74       "instance name". The unit is then constructed based on a "template
75       file" which serves as the definition of multiple services or other
76       units. A template unit must have a single "@" at the end of the name
77       (right before the type suffix). The name of the full unit is formed by
78       inserting the instance name between "@" and the unit type suffix. In
79       the unit file itself, the instance parameter may be referred to using
80       "%i" and other specifiers, see below.
81
82       Unit files may contain additional options on top of those listed here.
83       If systemd encounters an unknown option, it will write a warning log
84       message but continue loading the unit. If an option or section name is
85       prefixed with X-, it is ignored completely by systemd. Options within
86       an ignored section do not need the prefix. Applications may use this to
87       include additional information in the unit files.
88
89       Units can be aliased (have an alternative name), by creating a symlink
90       from the new name to the existing name in one of the unit search paths.
91       For example, systemd-networkd.service has the alias
92       dbus-org.freedesktop.network1.service, created during installation as a
93       symlink, so when systemd is asked through D-Bus to load
94       dbus-org.freedesktop.network1.service, it'll load
95       systemd-networkd.service. As another example, default.target — the
96       default system target started at boot — is commonly symlinked (aliased)
97       to either multi-user.target or graphical.target to select what is
98       started by default. Alias names may be used in commands like disable,
99       start, stop, status, and similar, and in all unit dependency
100       directives, including Wants=, Requires=, Before=, After=. Aliases
101       cannot be used with the preset command.
102
103       Aliases obey the following restrictions: a unit of a certain type
104       (".service", ".socket", ...) can only be aliased by a name with the
105       same type suffix. A plain unit (not a template or an instance), may
106       only be aliased by a plain name. A template instance may only be
107       aliased by another template instance, and the instance part must be
108       identical. A template may be aliased by another template (in which case
109       the alias applies to all instances of the template). As a special case,
110       a template instance (e.g.  "alias@inst.service") may be a symlink to
111       different template (e.g.  "template@inst.service"). In that case, just
112       this specific instance is aliased, while other instances of the
113       template (e.g.  "alias@foo.service", "alias@bar.service") are not
114       aliased. Those rule preserve the requirement that the instance (if any)
115       is always uniquely defined for a given unit and all its aliases.
116
117       Unit files may specify aliases through the Alias= directive in the
118       [Install] section. When the unit is enabled, symlinks will be created
119       for those names, and removed when the unit is disabled. For example,
120       reboot.target specifies Alias=ctrl-alt-del.target, so when enabled, the
121       symlink /etc/systemd/systemd/ctrl-alt-del.service pointing to the
122       reboot.target file will be created, and when Ctrl+Alt+Del is invoked,
123       systemd will look for the ctrl-alt-del.service and execute
124       reboot.service.  systemd does not look at the [Install] section at all
125       during normal operation, so any directives in that section only have an
126       effect through the symlinks created during enablement.
127
128       Along with a unit file foo.service, the directory foo.service.wants/
129       may exist. All unit files symlinked from such a directory are
130       implicitly added as dependencies of type Wants= to the unit. Similar
131       functionality exists for Requires= type dependencies as well, the
132       directory suffix is .requires/ in this case. This functionality is
133       useful to hook units into the start-up of other units, without having
134       to modify their unit files. For details about the semantics of Wants=,
135       see below. The preferred way to create symlinks in the .wants/ or
136       .requires/ directory of a unit file is by embedding the dependency in
137       [Install] section of the target unit, and creating the symlink in the
138       file system with the enable or preset commands of systemctl(1).
139
140       Along with a unit file foo.service, a "drop-in" directory
141       foo.service.d/ may exist. All files with the suffix ".conf" from this
142       directory will be parsed after the unit file itself is parsed. This is
143       useful to alter or add configuration settings for a unit, without
144       having to modify unit files. Drop-in files must contain appropriate
145       section headers. For instantiated units, this logic will first look for
146       the instance ".d/" subdirectory (e.g.  "foo@bar.service.d/") and read
147       its ".conf" files, followed by the template ".d/" subdirectory (e.g.
148       "foo@.service.d/") and the ".conf" files there. Moreover for units
149       names containing dashes ("-"), the set of directories generated by
150       truncating the unit name after all dashes is searched too.
151       Specifically, for a unit name foo-bar-baz.service not only the regular
152       drop-in directory foo-bar-baz.service.d/ is searched but also both
153       foo-bar-.service.d/ and foo-.service.d/. This is useful for defining
154       common drop-ins for a set of related units, whose names begin with a
155       common prefix. This scheme is particularly useful for mount, automount
156       and slice units, whose systematic naming structure is built around
157       dashes as component separators. Note that equally named drop-in files
158       further down the prefix hierarchy override those further up, i.e.
159       foo-bar-.service.d/10-override.conf overrides
160       foo-.service.d/10-override.conf.
161
162       In cases of unit aliases (described above), dropins for the aliased
163       name and all aliases are loaded. In the example of default.target
164       aliasing graphical.target, default.target.d/, default.target.wants/,
165       default.target.requires/, graphical.target.d/, graphical.target.wants/,
166       graphical.target.requires/ would all be read. For templates, dropins
167       for the template, any template aliases, the template instance, and all
168       alias instances are read. When just a specific template instance is
169       aliased, then the dropins for the target template, the target template
170       instance, and the alias template instance are read.
171
172       In addition to /etc/systemd/system, the drop-in ".d/" directories for
173       system services can be placed in /usr/lib/systemd/system or
174       /run/systemd/system directories. Drop-in files in /etc take precedence
175       over those in /run which in turn take precedence over those in
176       /usr/lib. Drop-in files under any of these directories take precedence
177       over unit files wherever located. Multiple drop-in files with different
178       names are applied in lexicographic order, regardless of which of the
179       directories they reside in.
180
181       Units also support a top-level drop-in with type.d/, where type may be
182       e.g.  "service" or "socket", that allows altering or adding to the
183       settings of all corresponding unit files on the system. The formatting
184       and precedence of applying drop-in configurations follow what is
185       defined above. Configurations in type.d/ have the lowest precedence
186       compared to settings in the name specific override directories. So the
187       contents of foo-.service.d/10-override.conf would override
188       service.d/10-override.conf.
189
190       Note that while systemd offers a flexible dependency system between
191       units it is recommended to use this functionality only sparingly and
192       instead rely on techniques such as bus-based or socket-based activation
193       which make dependencies implicit, resulting in a both simpler and more
194       flexible system.
195
196       As mentioned above, a unit may be instantiated from a template file.
197       This allows creation of multiple units from a single configuration
198       file. If systemd looks for a unit configuration file, it will first
199       search for the literal unit name in the file system. If that yields no
200       success and the unit name contains an "@" character, systemd will look
201       for a unit template that shares the same name but with the instance
202       string (i.e. the part between the "@" character and the suffix)
203       removed. Example: if a service getty@tty3.service is requested and no
204       file by that name is found, systemd will look for getty@.service and
205       instantiate a service from that configuration file if it is found.
206
207       To refer to the instance string from within the configuration file you
208       may use the special "%i" specifier in many of the configuration
209       options. See below for details.
210
211       If a unit file is empty (i.e. has the file size 0) or is symlinked to
212       /dev/null, its configuration will not be loaded and it appears with a
213       load state of "masked", and cannot be activated. Use this as an
214       effective way to fully disable a unit, making it impossible to start it
215       even manually.
216
217       The unit file format is covered by the Interface Stability Promise[1].
218

STRING ESCAPING FOR INCLUSION IN UNIT NAMES

220       Sometimes it is useful to convert arbitrary strings into unit names. To
221       facilitate this, a method of string escaping is used, in order to map
222       strings containing arbitrary byte values (except NUL) into valid unit
223       names and their restricted character set. A common special case are
224       unit names that reflect paths to objects in the file system hierarchy.
225       Example: a device unit dev-sda.device refers to a device with the
226       device node /dev/sda in the file system.
227
228       The escaping algorithm operates as follows: given a string, any "/"
229       character is replaced by "-", and all other characters which are not
230       ASCII alphanumerics or "_" are replaced by C-style "\x2d" escapes. In
231       addition, "."  is replaced with such a C-style escape when it would
232       appear as the first character in the escaped string.
233
234       When the input qualifies as absolute file system path, this algorithm
235       is extended slightly: the path to the root directory "/" is encoded as
236       single dash "-". In addition, any leading, trailing or duplicate "/"
237       characters are removed from the string before transformation. Example:
238       /foo//bar/baz/ becomes "foo-bar-baz".
239
240       This escaping is fully reversible, as long as it is known whether the
241       escaped string was a path (the unescaping results are different for
242       paths and non-path strings). The systemd-escape(1) command may be used
243       to apply and reverse escaping on arbitrary strings. Use systemd-escape
244       --path to escape path strings, and systemd-escape without --path
245       otherwise.
246

AUTOMATIC DEPENDENCIES

248   Implicit Dependencies
249       A number of unit dependencies are implicitly established, depending on
250       unit type and unit configuration. These implicit dependencies can make
251       unit configuration file cleaner. For the implicit dependencies in each
252       unit type, please refer to section "Implicit Dependencies" in
253       respective man pages.
254
255       For example, service units with Type=dbus automatically acquire
256       dependencies of type Requires= and After= on dbus.socket. See
257       systemd.service(5) for details.
258
259   Default Dependencies
260       Default dependencies are similar to implicit dependencies, but can be
261       turned on and off by setting DefaultDependencies= to yes (the default)
262       and no, while implicit dependencies are always in effect. See section
263       "Default Dependencies" in respective man pages for the effect of
264       enabling DefaultDependencies= in each unit types.
265
266       For example, target units will complement all configured dependencies
267       of type Wants= or Requires= with dependencies of type After= unless
268       DefaultDependencies=no is set in the specified units. See
269       systemd.target(5) for details. Note that this behavior can be turned
270       off by setting DefaultDependencies=no.
271

UNIT FILE LOAD PATH

273       Unit files are loaded from a set of paths determined during
274       compilation, described in the two tables below. Unit files found in
275       directories listed earlier override files with the same name in
276       directories lower in the list.
277
278       When the variable $SYSTEMD_UNIT_PATH is set, the contents of this
279       variable overrides the unit load path. If $SYSTEMD_UNIT_PATH ends with
280       an empty component (":"), the usual unit load path will be appended to
281       the contents of the variable.
282
283       Table 1.  Load path when running in system mode (--system).
284       ┌──────────────────────────────┬────────────────────────────┐
285Path                          Description                
286       ├──────────────────────────────┼────────────────────────────┤
287       │/etc/systemd/system.control   │ Persistent and transient   │
288       ├──────────────────────────────┤ configuration created      │
289       │/run/systemd/system.control   │ using the dbus API         │
290       ├──────────────────────────────┼────────────────────────────┤
291       │/run/systemd/transient        │ Dynamic configuration for  │
292       │                              │ transient units            │
293       ├──────────────────────────────┼────────────────────────────┤
294       │/run/systemd/generator.early  │ Generated units with high  │
295       │                              │ priority (see early-dir in │
296       │                              │ systemd.generator(7))      │
297       ├──────────────────────────────┼────────────────────────────┤
298       │/etc/systemd/system           │ System units created by    │
299       │                              │ the administrator          │
300       ├──────────────────────────────┼────────────────────────────┤
301       │/run/systemd/system           │ Runtime units              │
302       ├──────────────────────────────┼────────────────────────────┤
303       │/run/systemd/generator        │ Generated units with       │
304       │                              │ medium priority (see       │
305       │                              │ normal-dir in              │
306       │                              │ systemd.generator(7))      │
307       ├──────────────────────────────┼────────────────────────────┤
308       │/usr/local/lib/systemd/system │ System units installed by  │
309       │                              │ the administrator          │
310       ├──────────────────────────────┼────────────────────────────┤
311       │/usr/lib/systemd/system       │ System units installed by  │
312       │                              │ the distribution package   │
313       │                              │ manager                    │
314       ├──────────────────────────────┼────────────────────────────┤
315       │/run/systemd/generator.late   │ Generated units with low   │
316       │                              │ priority (see late-dir in  │
317       │                              │ systemd.generator(7))      │
318       └──────────────────────────────┴────────────────────────────┘
319
320       Table 2.  Load path when running in user mode (--user).
321       ┌────────────────────────────────────────┬────────────────────────────┐
322Path                                    Description                
323       ├────────────────────────────────────────┼────────────────────────────┤
324       │$XDG_CONFIG_HOME/systemd/user.control   │ Persistent and transient   │
325       │or                                      │ configuration created      │
326       │~/.config/systemd/user.control          │ using the dbus API         │
327       ├────────────────────────────────────────┤ ($XDG_CONFIG_HOME is used  │
328       │$XDG_RUNTIME_DIR/systemd/user.control   │ if set, ~/.config          │
329       │                                        │ otherwise)                 │
330       ├────────────────────────────────────────┼────────────────────────────┤
331       │/run/systemd/transient                  │ Dynamic configuration for  │
332       │                                        │ transient units            │
333       ├────────────────────────────────────────┼────────────────────────────┤
334       │/run/systemd/generator.early            │ Generated units with high  │
335       │                                        │ priority (see early-dir in │
336       │                                        │ systemd.generator(7))      │
337       ├────────────────────────────────────────┼────────────────────────────┤
338       │$XDG_CONFIG_HOME/systemd/user or        │ User configuration         │
339       │$HOME/.config/systemd/user              │ ($XDG_CONFIG_HOME is used  │
340       │                                        │ if set, ~/.config          │
341       │                                        │ otherwise)                 │
342       ├────────────────────────────────────────┼────────────────────────────┤
343       │/etc/systemd/user                       │ User units created by the  │
344       │                                        │ administrator              │
345       ├────────────────────────────────────────┼────────────────────────────┤
346       │$XDG_RUNTIME_DIR/systemd/user           │ Runtime units (only used   │
347       │                                        │ when $XDG_RUNTIME_DIR is   │
348       │                                        │ set)                       │
349       ├────────────────────────────────────────┼────────────────────────────┤
350       │/run/systemd/user                       │ Runtime units              │
351       ├────────────────────────────────────────┼────────────────────────────┤
352       │$XDG_RUNTIME_DIR/systemd/generator      │ Generated units with       │
353       │                                        │ medium priority (see       │
354       │                                        │ normal-dir in              │
355       │                                        │ systemd.generator(7))      │
356       ├────────────────────────────────────────┼────────────────────────────┤
357       │$XDG_DATA_HOME/systemd/user or          │ Units of packages that     │
358       │$HOME/.local/share/systemd/user         │ have been installed in the │
359       │                                        │ home directory             │
360       │                                        │ ($XDG_DATA_HOME is used if │
361       │                                        │ set, ~/.local/share        │
362       │                                        │ otherwise)                 │
363       ├────────────────────────────────────────┼────────────────────────────┤
364       │$dir/systemd/user for each $dir in      │ Additional locations for   │
365$XDG_DATA_DIRS                          │ installed user units, one  │
366       │                                        │ for each entry in          │
367       │                                        │ $XDG_DATA_DIRS
368       ├────────────────────────────────────────┼────────────────────────────┤
369       │/usr/local/lib/systemd/user             │ User units installed by    │
370       │                                        │ the administrator          │
371       ├────────────────────────────────────────┼────────────────────────────┤
372       │/usr/lib/systemd/user                   │ User units installed by    │
373       │                                        │ the distribution package   │
374       │                                        │ manager                    │
375       ├────────────────────────────────────────┼────────────────────────────┤
376       │$XDG_RUNTIME_DIR/systemd/generator.late │ Generated units with low   │
377       │                                        │ priority (see late-dir in  │
378       │                                        │ systemd.generator(7))      │
379       └────────────────────────────────────────┴────────────────────────────┘
380
381       The set of load paths for the user manager instance may be augmented or
382       changed using various environment variables. And environment variables
383       may in turn be set using environment generators, see
384       systemd.environment-generator(7). In particular, $XDG_DATA_HOME and
385       $XDG_DATA_DIRS may be easily set using systemd-environment-d-
386       generator(8). Thus, directories listed here are just the defaults. To
387       see the actual list that would be used based on compilation options and
388       current environment use
389
390           systemd-analyze --user unit-paths
391
392       Moreover, additional units might be loaded into systemd from
393       directories not on the unit load path by creating a symlink pointing to
394       a unit file in the directories. You can use systemctl link for this
395       operation. See systemctl(1) for its usage and precaution.
396

UNIT GARBAGE COLLECTION

398       The system and service manager loads a unit's configuration
399       automatically when a unit is referenced for the first time. It will
400       automatically unload the unit configuration and state again when the
401       unit is not needed anymore ("garbage collection"). A unit may be
402       referenced through a number of different mechanisms:
403
404        1. Another loaded unit references it with a dependency such as After=,
405           Wants=, ...
406
407        2. The unit is currently starting, running, reloading or stopping.
408
409        3. The unit is currently in the failed state. (But see below.)
410
411        4. A job for the unit is pending.
412
413        5. The unit is pinned by an active IPC client program.
414
415        6. The unit is a special "perpetual" unit that is always active and
416           loaded. Examples for perpetual units are the root mount unit
417           -.mount or the scope unit init.scope that the service manager
418           itself lives in.
419
420        7. The unit has running processes associated with it.
421
422       The garbage collection logic may be altered with the CollectMode=
423       option, which allows configuration whether automatic unloading of units
424       that are in failed state is permissible, see below.
425
426       Note that when a unit's configuration and state is unloaded, all
427       execution results, such as exit codes, exit signals, resource
428       consumption and other statistics are lost, except for what is stored in
429       the log subsystem.
430
431       Use systemctl daemon-reload or an equivalent command to reload unit
432       configuration while the unit is already loaded. In this case all
433       configuration settings are flushed out and replaced with the new
434       configuration (which however might not be in effect immediately),
435       however all runtime state is saved/restored.
436

[UNIT] SECTION OPTIONS

438       The unit file may include a [Unit] section, which carries generic
439       information about the unit that is not dependent on the type of unit:
440
441       Description=
442           A human readable name for the unit. This is used by systemd (and
443           other UIs) as the label for the unit, so this string should
444           identify the unit rather than describe it, despite the name.
445           "Apache2 Web Server" is a good example. Bad examples are
446           "high-performance light-weight HTTP server" (too generic) or
447           "Apache2" (too specific and meaningless for people who do not know
448           Apache).  systemd will use this string as a noun in status messages
449           ("Starting description...", "Started description.", "Reached target
450           description.", "Failed to start description."), so it should be
451           capitalized, and should not be a full sentence or a phrase with a
452           continuous verb. Bad examples include "exiting the container" or
453           "updating the database once per day.".
454
455       Documentation=
456           A space-separated list of URIs referencing documentation for this
457           unit or its configuration. Accepted are only URIs of the types
458           "http://", "https://", "file:", "info:", "man:". For more
459           information about the syntax of these URIs, see uri(7). The URIs
460           should be listed in order of relevance, starting with the most
461           relevant. It is a good idea to first reference documentation that
462           explains what the unit's purpose is, followed by how it is
463           configured, followed by any other related documentation. This
464           option may be specified more than once, in which case the specified
465           list of URIs is merged. If the empty string is assigned to this
466           option, the list is reset and all prior assignments will have no
467           effect.
468
469       Wants=
470           Configures requirement dependencies on other units. This option may
471           be specified more than once or multiple space-separated units may
472           be specified in one option in which case dependencies for all
473           listed names will be created. Dependencies of this type may also be
474           configured outside of the unit configuration file by adding a
475           symlink to a .wants/ directory accompanying the unit file. For
476           details, see above.
477
478           Units listed in this option will be started if the configuring unit
479           is. However, if the listed units fail to start or cannot be added
480           to the transaction, this has no impact on the validity of the
481           transaction as a whole, and this unit will still be started. This
482           is the recommended way to hook the start-up of one unit to the
483           start-up of another unit.
484
485           Note that requirement dependencies do not influence the order in
486           which services are started or stopped. This has to be configured
487           independently with the After= or Before= options. If unit
488           foo.service pulls in unit bar.service as configured with Wants= and
489           no ordering is configured with After= or Before=, then both units
490           will be started simultaneously and without any delay between them
491           if foo.service is activated.
492
493       Requires=
494           Similar to Wants=, but declares a stronger dependency. Dependencies
495           of this type may also be configured by adding a symlink to a
496           .requires/ directory accompanying the unit file.
497
498           If this unit gets activated, the units listed will be activated as
499           well. If one of the other units fails to activate, and an ordering
500           dependency After= on the failing unit is set, this unit will not be
501           started. Besides, with or without specifying After=, this unit will
502           be stopped if one of the other units is explicitly stopped.
503
504           Often, it is a better choice to use Wants= instead of Requires= in
505           order to achieve a system that is more robust when dealing with
506           failing services.
507
508           Note that this dependency type does not imply that the other unit
509           always has to be in active state when this unit is running.
510           Specifically: failing condition checks (such as
511           ConditionPathExists=, ConditionPathIsSymbolicLink=, ... — see
512           below) do not cause the start job of a unit with a Requires=
513           dependency on it to fail. Also, some unit types may deactivate on
514           their own (for example, a service process may decide to exit
515           cleanly, or a device may be unplugged by the user), which is not
516           propagated to units having a Requires= dependency. Use the BindsTo=
517           dependency type together with After= to ensure that a unit may
518           never be in active state without a specific other unit also in
519           active state (see below).
520
521       Requisite=
522           Similar to Requires=. However, if the units listed here are not
523           started already, they will not be started and the starting of this
524           unit will fail immediately.  Requisite= does not imply an ordering
525           dependency, even if both units are started in the same transaction.
526           Hence this setting should usually be combined with After=, to
527           ensure this unit is not started before the other unit.
528
529           When Requisite=b.service is used on a.service, this dependency will
530           show as RequisiteOf=a.service in property listing of b.service.
531           RequisiteOf= dependency cannot be specified directly.
532
533       BindsTo=
534           Configures requirement dependencies, very similar in style to
535           Requires=. However, this dependency type is stronger: in addition
536           to the effect of Requires= it declares that if the unit bound to is
537           stopped, this unit will be stopped too. This means a unit bound to
538           another unit that suddenly enters inactive state will be stopped
539           too. Units can suddenly, unexpectedly enter inactive state for
540           different reasons: the main process of a service unit might
541           terminate on its own choice, the backing device of a device unit
542           might be unplugged or the mount point of a mount unit might be
543           unmounted without involvement of the system and service manager.
544
545           When used in conjunction with After= on the same unit the behaviour
546           of BindsTo= is even stronger. In this case, the unit bound to
547           strictly has to be in active state for this unit to also be in
548           active state. This not only means a unit bound to another unit that
549           suddenly enters inactive state, but also one that is bound to
550           another unit that gets skipped due to a failed condition check
551           (such as ConditionPathExists=, ConditionPathIsSymbolicLink=, ... —
552           see below) will be stopped, should it be running. Hence, in many
553           cases it is best to combine BindsTo= with After=.
554
555           When BindsTo=b.service is used on a.service, this dependency will
556           show as BoundBy=a.service in property listing of b.service.
557           BoundBy= dependency cannot be specified directly.
558
559       PartOf=
560           Configures dependencies similar to Requires=, but limited to
561           stopping and restarting of units. When systemd stops or restarts
562           the units listed here, the action is propagated to this unit. Note
563           that this is a one-way dependency — changes to this unit do not
564           affect the listed units.
565
566           When PartOf=b.service is used on a.service, this dependency will
567           show as ConsistsOf=a.service in property listing of b.service.
568           ConsistsOf= dependency cannot be specified directly.
569
570       Conflicts=
571           A space-separated list of unit names. Configures negative
572           requirement dependencies. If a unit has a Conflicts= setting on
573           another unit, starting the former will stop the latter and vice
574           versa.
575
576           Note that this setting does not imply an ordering dependency,
577           similarly to the Wants= and Requires= dependencies described above.
578           This means that to ensure that the conflicting unit is stopped
579           before the other unit is started, an After= or Before= dependency
580           must be declared. It doesn't matter which of the two ordering
581           dependencies is used, because stop jobs are always ordered before
582           start jobs, see the discussion in Before=/After= below.
583
584           If unit A that conflicts with unit B is scheduled to be started at
585           the same time as B, the transaction will either fail (in case both
586           are required parts of the transaction) or be modified to be fixed
587           (in case one or both jobs are not a required part of the
588           transaction). In the latter case, the job that is not required will
589           be removed, or in case both are not required, the unit that
590           conflicts will be started and the unit that is conflicted is
591           stopped.
592
593       Before=, After=
594           These two settings expect a space-separated list of unit names.
595           They may be specified more than once, in which case dependencies
596           for all listed names are created.
597
598           Those two settings configure ordering dependencies between units.
599           If unit foo.service contains the setting Before=bar.service and
600           both units are being started, bar.service's start-up is delayed
601           until foo.service has finished starting up.  After= is the inverse
602           of Before=, i.e. while Before= ensures that the configured unit is
603           started before the listed unit begins starting up, After= ensures
604           the opposite, that the listed unit is fully started up before the
605           configured unit is started.
606
607           When two units with an ordering dependency between them are shut
608           down, the inverse of the start-up order is applied. i.e. if a unit
609           is configured with After= on another unit, the former is stopped
610           before the latter if both are shut down. Given two units with any
611           ordering dependency between them, if one unit is shut down and the
612           other is started up, the shutdown is ordered before the start-up.
613           It doesn't matter if the ordering dependency is After= or Before=,
614           in this case. It also doesn't matter which of the two is shut down,
615           as long as one is shut down and the other is started up; the
616           shutdown is ordered before the start-up in all cases. If two units
617           have no ordering dependencies between them, they are shut down or
618           started up simultaneously, and no ordering takes place. It depends
619           on the unit type when precisely a unit has finished starting up.
620           Most importantly, for service units start-up is considered
621           completed for the purpose of Before=/After= when all its configured
622           start-up commands have been invoked and they either failed or
623           reported start-up success.
624
625           Note that those settings are independent of and orthogonal to the
626           requirement dependencies as configured by Requires=, Wants=,
627           Requisite=, or BindsTo=. It is a common pattern to include a unit
628           name in both the After= and Wants= options, in which case the unit
629           listed will be started before the unit that is configured with
630           these options.
631
632           Note that Before= dependencies on device units have no effect and
633           are not supported. Devices generally become available as a result
634           of an external hotplug event, and systemd creates the corresponding
635           device unit without delay.
636
637       OnFailure=
638           A space-separated list of one or more units that are activated when
639           this unit enters the "failed" state. A service unit using Restart=
640           enters the failed state only after the start limits are reached.
641
642       PropagatesReloadTo=, ReloadPropagatedFrom=
643           A space-separated list of one or more units where reload requests
644           on this unit will be propagated to, or reload requests on the other
645           unit will be propagated to this unit, respectively. Issuing a
646           reload request on a unit will automatically also enqueue a reload
647           request on all units that the reload request shall be propagated to
648           via these two settings.
649
650       JoinsNamespaceOf=
651           For units that start processes (such as service units), lists one
652           or more other units whose network and/or temporary file namespace
653           to join. This only applies to unit types which support the
654           PrivateNetwork=, NetworkNamespacePath= and PrivateTmp= directives
655           (see systemd.exec(5) for details). If a unit that has this setting
656           set is started, its processes will see the same /tmp, /var/tmp and
657           network namespace as one listed unit that is started. If multiple
658           listed units are already started, it is not defined which namespace
659           is joined. Note that this setting only has an effect if
660           PrivateNetwork=/NetworkNamespacePath= and/or PrivateTmp= is enabled
661           for both the unit that joins the namespace and the unit whose
662           namespace is joined.
663
664       RequiresMountsFor=
665           Takes a space-separated list of absolute paths. Automatically adds
666           dependencies of type Requires= and After= for all mount units
667           required to access the specified path.
668
669           Mount points marked with noauto are not mounted automatically
670           through local-fs.target, but are still honored for the purposes of
671           this option, i.e. they will be pulled in by this unit.
672
673       OnFailureJobMode=
674           Takes a value of "fail", "replace", "replace-irreversibly",
675           "isolate", "flush", "ignore-dependencies" or "ignore-requirements".
676           Defaults to "replace". Specifies how the units listed in OnFailure=
677           will be enqueued. See systemctl(1)'s --job-mode= option for details
678           on the possible values. If this is set to "isolate", only a single
679           unit may be listed in OnFailure=..
680
681       IgnoreOnIsolate=
682           Takes a boolean argument. If true, this unit will not be stopped
683           when isolating another unit. Defaults to false for service, target,
684           socket, busname, timer, and path units, and true for slice, scope,
685           device, swap, mount, and automount units.
686
687       StopWhenUnneeded=
688           Takes a boolean argument. If true, this unit will be stopped when
689           it is no longer used. Note that, in order to minimize the work to
690           be executed, systemd will not stop units by default unless they are
691           conflicting with other units, or the user explicitly requested
692           their shut down. If this option is set, a unit will be
693           automatically cleaned up if no other active unit requires it.
694           Defaults to false.
695
696       RefuseManualStart=, RefuseManualStop=
697           Takes a boolean argument. If true, this unit can only be activated
698           or deactivated indirectly. In this case, explicit start-up or
699           termination requested by the user is denied, however if it is
700           started or stopped as a dependency of another unit, start-up or
701           termination will succeed. This is mostly a safety feature to ensure
702           that the user does not accidentally activate units that are not
703           intended to be activated explicitly, and not accidentally
704           deactivate units that are not intended to be deactivated. These
705           options default to false.
706
707       AllowIsolate=
708           Takes a boolean argument. If true, this unit may be used with the
709           systemctl isolate command. Otherwise, this will be refused. It
710           probably is a good idea to leave this disabled except for target
711           units that shall be used similar to runlevels in SysV init systems,
712           just as a precaution to avoid unusable system states. This option
713           defaults to false.
714
715       DefaultDependencies=
716           Takes a boolean argument. If yes, (the default), a few default
717           dependencies will implicitly be created for the unit. The actual
718           dependencies created depend on the unit type. For example, for
719           service units, these dependencies ensure that the service is
720           started only after basic system initialization is completed and is
721           properly terminated on system shutdown. See the respective man
722           pages for details. Generally, only services involved with early
723           boot or late shutdown should set this option to no. It is highly
724           recommended to leave this option enabled for the majority of common
725           units. If set to no, this option does not disable all implicit
726           dependencies, just non-essential ones.
727
728       CollectMode=
729           Tweaks the "garbage collection" algorithm for this unit. Takes one
730           of inactive or inactive-or-failed. If set to inactive the unit will
731           be unloaded if it is in the inactive state and is not referenced by
732           clients, jobs or other units — however it is not unloaded if it is
733           in the failed state. In failed mode, failed units are not unloaded
734           until the user invoked systemctl reset-failed on them to reset the
735           failed state, or an equivalent command. This behaviour is altered
736           if this option is set to inactive-or-failed: in this case the unit
737           is unloaded even if the unit is in a failed state, and thus an
738           explicitly resetting of the failed state is not necessary. Note
739           that if this mode is used unit results (such as exit codes, exit
740           signals, consumed resources, ...) are flushed out immediately after
741           the unit completed, except for what is stored in the logging
742           subsystem. Defaults to inactive.
743
744       FailureAction=, SuccessAction=
745           Configure the action to take when the unit stops and enters a
746           failed state or inactive state. Takes one of none, reboot,
747           reboot-force, reboot-immediate, poweroff, poweroff-force,
748           poweroff-immediate, exit, and exit-force. In system mode, all
749           options are allowed. In user mode, only none, exit, and exit-force
750           are allowed. Both options default to none.
751
752           If none is set, no action will be triggered.  reboot causes a
753           reboot following the normal shutdown procedure (i.e. equivalent to
754           systemctl reboot).  reboot-force causes a forced reboot which will
755           terminate all processes forcibly but should cause no dirty file
756           systems on reboot (i.e. equivalent to systemctl reboot -f) and
757           reboot-immediate causes immediate execution of the reboot(2) system
758           call, which might result in data loss (i.e. equivalent to systemctl
759           reboot -ff). Similarly, poweroff, poweroff-force,
760           poweroff-immediate have the effect of powering down the system with
761           similar semantics.  exit causes the manager to exit following the
762           normal shutdown procedure, and exit-force causes it terminate
763           without shutting down services. When exit or exit-force is used by
764           default the exit status of the main process of the unit (if this
765           applies) is returned from the service manager. However, this may be
766           overridden with FailureActionExitStatus=/SuccessActionExitStatus=,
767           see below.
768
769       FailureActionExitStatus=, SuccessActionExitStatus=
770           Controls the exit status to propagate back to an invoking container
771           manager (in case of a system service) or service manager (in case
772           of a user manager) when the FailureAction=/SuccessAction= are set
773           to exit or exit-force and the action is triggered. By default the
774           exit status of the main process of the triggering unit (if this
775           applies) is propagated. Takes a value in the range 0...255 or the
776           empty string to request default behaviour.
777
778       JobTimeoutSec=, JobRunningTimeoutSec=
779           When a job for this unit is queued, a timeout JobTimeoutSec= may be
780           configured. Similarly, JobRunningTimeoutSec= starts counting when
781           the queued job is actually started. If either time limit is
782           reached, the job will be cancelled, the unit however will not
783           change state or even enter the "failed" mode. This value defaults
784           to "infinity" (job timeouts disabled), except for device units
785           (JobRunningTimeoutSec= defaults to DefaultTimeoutStartSec=). NB:
786           this timeout is independent from any unit-specific timeout (for
787           example, the timeout set with TimeoutStartSec= in service units) as
788           the job timeout has no effect on the unit itself, only on the job
789           that might be pending for it. Or in other words: unit-specific
790           timeouts are useful to abort unit state changes, and revert them.
791           The job timeout set with this option however is useful to abort
792           only the job waiting for the unit state to change.
793
794       JobTimeoutAction=, JobTimeoutRebootArgument=
795           JobTimeoutAction= optionally configures an additional action to
796           take when the timeout is hit, see description of JobTimeoutSec= and
797           JobRunningTimeoutSec= above. It takes the same values as
798           StartLimitAction=. Defaults to none.  JobTimeoutRebootArgument=
799           configures an optional reboot string to pass to the reboot(2)
800           system call.
801
802       StartLimitIntervalSec=interval, StartLimitBurst=burst
803           Configure unit start rate limiting. Units which are started more
804           than burst times within an interval time interval are not permitted
805           to start any more. Use StartLimitIntervalSec= to configure the
806           checking interval (defaults to DefaultStartLimitIntervalSec= in
807           manager configuration file, set it to 0 to disable any kind of rate
808           limiting). Use StartLimitBurst= to configure how many starts per
809           interval are allowed (defaults to DefaultStartLimitBurst= in
810           manager configuration file). These configuration options are
811           particularly useful in conjunction with the service setting
812           Restart= (see systemd.service(5)); however, they apply to all kinds
813           of starts (including manual), not just those triggered by the
814           Restart= logic. Note that units which are configured for Restart=
815           and which reach the start limit are not attempted to be restarted
816           anymore; however, they may still be restarted manually at a later
817           point, after the interval has passed. From this point on, the
818           restart logic is activated again. Note that systemctl reset-failed
819           will cause the restart rate counter for a service to be flushed,
820           which is useful if the administrator wants to manually start a unit
821           and the start limit interferes with that. Note that this
822           rate-limiting is enforced after any unit condition checks are
823           executed, and hence unit activations with failing conditions do not
824           count towards this rate limit. This setting does not apply to
825           slice, target, device, and scope units, since they are unit types
826           whose activation may either never fail, or may succeed only a
827           single time.
828
829           When a unit is unloaded due to the garbage collection logic (see
830           above) its rate limit counters are flushed out too. This means that
831           configuring start rate limiting for a unit that is not referenced
832           continuously has no effect.
833
834       StartLimitAction=
835           Configure an additional action to take if the rate limit configured
836           with StartLimitIntervalSec= and StartLimitBurst= is hit. Takes the
837           same values as the setting FailureAction=/SuccessAction= settings
838           and executes the same actions. If none is set, hitting the rate
839           limit will trigger no action besides that the start will not be
840           permitted. Defaults to none.
841
842       RebootArgument=
843           Configure the optional argument for the reboot(2) system call if
844           StartLimitAction= or FailureAction= is a reboot action. This works
845           just like the optional argument to systemctl reboot command.
846
847       SourcePath=
848           A path to a configuration file this unit has been generated from.
849           This is primarily useful for implementation of generator tools that
850           convert configuration from an external configuration file format
851           into native unit files. This functionality should not be used in
852           normal units.
853
854   Conditions and Asserts
855       Unit files may also include a number of Condition...= and Assert...=
856       settings. Before the unit is started, systemd will verify that the
857       specified conditions are true. If not, the starting of the unit will be
858       (mostly silently) skipped. Failing conditions will not result in the
859       unit being moved into the "failed" state. The conditions are checked at
860       the time the queued start job is to be executed. The ordering
861       dependencies are still respected, so other units are still pulled in
862       and ordered as if this unit was successfully activated. Use condition
863       expressions in order to skip units that do not apply to the local
864       system, for example because the kernel or runtime environment doesn't
865       require their functionality.
866
867       If multiple conditions are specified, the unit will be executed if all
868       of them apply (i.e. a logical AND is applied). Condition checks can use
869       a pipe symbol ("|") after the equals sign ("Condition...=|..."), which
870       causes the condition becomes a triggering condition. If at least one
871       triggering condition is defined for a unit, then the unit will be
872       executed if at least one of the triggering conditions apply and all of
873       the non-triggering conditions. If you prefix an argument with the pipe
874       symbol and an exclamation mark, the pipe symbol must be passed first,
875       the exclamation second. If any of these options is assigned the empty
876       string, the list of conditions is reset completely, all previous
877       condition settings (of any kind) will have no effect.
878
879       The AssertArchitecture=, AssertVirtualization=, ... options provide a
880       similar mechanism that causes the job to fail (instead of being
881       skipped). The failed check is logged. Units with failed conditions are
882       considered to be in a clean state and will be garbage collected if they
883       are not referenced. This means that when queried, the condition failure
884       may or may not show up in the state of the unit.
885
886       Note that neither assertion nor condition expressions result in unit
887       state changes. Also note that both are checked at the time the job is
888       to be executed, i.e. long after depending jobs and it itself were
889       queued. Thus, neither condition nor assertion expressions are suitable
890       for conditionalizing unit dependencies.
891
892       The condition verb of systemd-analyze(1) can be used to test condition
893       and assert expressions.
894
895       Except for ConditionPathIsSymbolicLink=, all path checks follow
896       symlinks.
897
898       ConditionArchitecture=
899           Check whether the system is running on a specific architecture.
900           Takes one of "x86", "x86-64", "ppc", "ppc-le", "ppc64", "ppc64-le",
901           "ia64", "parisc", "parisc64", "s390", "s390x", "sparc", "sparc64",
902           "mips", "mips-le", "mips64", "mips64-le", "alpha", "arm", "arm-be",
903           "arm64", "arm64-be", "sh", "sh64", "m68k", "tilegx", "cris", "arc",
904           "arc-be", or "native".
905
906           The architecture is determined from the information returned by
907           uname(2) and is thus subject to personality(2). Note that a
908           Personality= setting in the same unit file has no effect on this
909           condition. A special architecture name "native" is mapped to the
910           architecture the system manager itself is compiled for. The test
911           may be negated by prepending an exclamation mark.
912
913       ConditionVirtualization=
914           Check whether the system is executed in a virtualized environment
915           and optionally test whether it is a specific implementation. Takes
916           either boolean value to check if being executed in any virtualized
917           environment, or one of "vm" and "container" to test against a
918           generic type of virtualization solution, or one of "qemu", "kvm",
919           "zvm", "vmware", "microsoft", "oracle", "xen", "bochs", "uml",
920           "bhyve", "qnx", "openvz", "lxc", "lxc-libvirt", "systemd-nspawn",
921           "docker", "podman", "rkt", "wsl", "acrn" to test against a specific
922           implementation, or "private-users" to check whether we are running
923           in a user namespace. See systemd-detect-virt(1) for a full list of
924           known virtualization technologies and their identifiers. If
925           multiple virtualization technologies are nested, only the innermost
926           is considered. The test may be negated by prepending an exclamation
927           mark.
928
929       ConditionHost=
930           ConditionHost= may be used to match against the hostname or machine
931           ID of the host. This either takes a hostname string (optionally
932           with shell style globs) which is tested against the locally set
933           hostname as returned by gethostname(2), or a machine ID formatted
934           as string (see machine-id(5)). The test may be negated by
935           prepending an exclamation mark.
936
937       ConditionKernelCommandLine=
938           ConditionKernelCommandLine= may be used to check whether a specific
939           kernel command line option is set (or if prefixed with the
940           exclamation mark — unset). The argument must either be a single
941           word, or an assignment (i.e. two words, separated by "="). In the
942           former case the kernel command line is searched for the word
943           appearing as is, or as left hand side of an assignment. In the
944           latter case, the exact assignment is looked for with right and left
945           hand side matching.
946
947       ConditionKernelVersion=
948           ConditionKernelVersion= may be used to check whether the kernel
949           version (as reported by uname -r) matches a certain expression (or
950           if prefixed with the exclamation mark does not match it). The
951           argument must be a list of (potentially quoted) expressions. For
952           each of the expressions, if it starts with one of "<", "<=", "=",
953           "!=", ">=", ">" a relative version comparison is done, otherwise
954           the specified string is matched with shell-style globs.
955
956           Note that using the kernel version string is an unreliable way to
957           determine which features are supported by a kernel, because of the
958           widespread practice of backporting drivers, features, and fixes
959           from newer upstream kernels into older versions provided by
960           distributions. Hence, this check is inherently unportable and
961           should not be used for units which may be used on different
962           distributions.
963
964       ConditionSecurity=
965           ConditionSecurity= may be used to check whether the given security
966           technology is enabled on the system. Currently, the recognized
967           values are "selinux", "apparmor", "tomoyo", "ima", "smack", "audit"
968           and "uefi-secureboot". The test may be negated by prepending an
969           exclamation mark.
970
971       ConditionCapability=
972           Check whether the given capability exists in the capability
973           bounding set of the service manager (i.e. this does not check
974           whether capability is actually available in the permitted or
975           effective sets, see capabilities(7) for details). Pass a capability
976           name such as "CAP_MKNOD", possibly prefixed with an exclamation
977           mark to negate the check.
978
979       ConditionACPower=
980           Check whether the system has AC power, or is exclusively battery
981           powered at the time of activation of the unit. This takes a boolean
982           argument. If set to "true", the condition will hold only if at
983           least one AC connector of the system is connected to a power
984           source, or if no AC connectors are known. Conversely, if set to
985           "false", the condition will hold only if there is at least one AC
986           connector known and all AC connectors are disconnected from a power
987           source.
988
989       ConditionNeedsUpdate=
990           Takes one of /var or /etc as argument, possibly prefixed with a "!"
991           (to inverting the condition). This condition may be used to
992           conditionalize units on whether the specified directory requires an
993           update because /usr's modification time is newer than the stamp
994           file .updated in the specified directory. This is useful to
995           implement offline updates of the vendor operating system resources
996           in /usr that require updating of /etc or /var on the next following
997           boot. Units making use of this condition should order themselves
998           before systemd-update-done.service(8), to make sure they run before
999           the stamp file's modification time gets reset indicating a
1000           completed update.
1001
1002       ConditionFirstBoot=
1003           Takes a boolean argument. This condition may be used to
1004           conditionalize units on whether the system is booting up with an
1005           unpopulated /etc directory (specifically: an /etc with no
1006           /etc/machine-id). This may be used to populate /etc on the first
1007           boot after factory reset, or when a new system instance boots up
1008           for the first time.
1009
1010       ConditionPathExists=
1011           Check for the exists of a file. If the specified absolute path name
1012           does not exist, the condition will fail. If the absolute path name
1013           passed to ConditionPathExists= is prefixed with an exclamation mark
1014           ("!"), the test is negated, and the unit is only started if the
1015           path does not exist.
1016
1017       ConditionPathExistsGlob=
1018           ConditionPathExistsGlob= is similar to ConditionPathExists=, but
1019           checks for the existence of at least one file or directory matching
1020           the specified globbing pattern.
1021
1022       ConditionPathIsDirectory=
1023           ConditionPathIsDirectory= is similar to ConditionPathExists= but
1024           verifies that a certain path exists and is a directory.
1025
1026       ConditionPathIsSymbolicLink=
1027           ConditionPathIsSymbolicLink= is similar to ConditionPathExists= but
1028           verifies that a certain path exists and is a symbolic link.
1029
1030       ConditionPathIsMountPoint=
1031           ConditionPathIsMountPoint= is similar to ConditionPathExists= but
1032           verifies that a certain path exists and is a mount point.
1033
1034       ConditionPathIsReadWrite=
1035           ConditionPathIsReadWrite= is similar to ConditionPathExists= but
1036           verifies that the underlying file system is readable and writable
1037           (i.e. not mounted read-only).
1038
1039       ConditionDirectoryNotEmpty=
1040           ConditionDirectoryNotEmpty= is similar to ConditionPathExists= but
1041           verifies that a certain path exists and is a non-empty directory.
1042
1043       ConditionFileNotEmpty=
1044           ConditionFileNotEmpty= is similar to ConditionPathExists= but
1045           verifies that a certain path exists and refers to a regular file
1046           with a non-zero size.
1047
1048       ConditionFileIsExecutable=
1049           ConditionFileIsExecutable= is similar to ConditionPathExists= but
1050           verifies that a certain path exists, is a regular file, and marked
1051           executable.
1052
1053       ConditionUser=
1054           ConditionUser= takes a numeric "UID", a UNIX user name, or the
1055           special value "@system". This condition may be used to check
1056           whether the service manager is running as the given user. The
1057           special value "@system" can be used to check if the user id is
1058           within the system user range. This option is not useful for system
1059           services, as the system manager exclusively runs as the root user,
1060           and thus the test result is constant.
1061
1062       ConditionGroup=
1063           ConditionGroup= is similar to ConditionUser= but verifies that the
1064           service manager's real or effective group, or any of its auxiliary
1065           groups, match the specified group or GID. This setting does not
1066           support the special value "@system".
1067
1068       ConditionControlGroupController=
1069           Verify that the given cgroup controller (eg.  "cpu") is available
1070           for use on the system. For example, a particular controller may not
1071           be available if it was disabled on the kernel command line with
1072           cgroup_disable=controller. Multiple controllers may be passed with
1073           a space separating them; in this case the condition will only pass
1074           if all listed controllers are available for use. Controllers
1075           unknown to systemd are ignored. Valid controllers are "cpu",
1076           "cpuacct", "io", "blkio", "memory", "devices", and "pids".
1077
1078       ConditionMemory=
1079           Verify that the specified amount of system memory is available to
1080           the current system. Takes a memory size in bytes as argument,
1081           optionally prefixed with a comparison operator "<", "<=", "=",
1082           "!=", ">=", ">". On bare-metal systems compares the amount of
1083           physical memory in the system with the specified size, adhering to
1084           the specified comparison operator. In containers compares the
1085           amount of memory assigned to the container instead.
1086
1087       ConditionCPUs=
1088           Verify that the specified number of CPUs is available to the
1089           current system. Takes a number of CPUs as argument, optionally
1090           prefixed with a comparison operator "<", "<=", "=", "!=", ">=",
1091           ">". Compares the number of CPUs in the CPU affinity mask
1092           configured of the service manager itself with the specified number,
1093           adhering to the specified comparison operator. On physical systems
1094           the number of CPUs in the affinity mask of the service manager
1095           usually matches the number of physical CPUs, but in special and
1096           virtual environments might differ. In particular, in containers the
1097           affinity mask usually matches the number of CPUs assigned to the
1098           container and not the physically available ones.
1099
1100       AssertArchitecture=, AssertVirtualization=, AssertHost=,
1101       AssertKernelCommandLine=, AssertKernelVersion=, AssertSecurity=,
1102       AssertCapability=, AssertACPower=, AssertNeedsUpdate=,
1103       AssertFirstBoot=, AssertPathExists=, AssertPathExistsGlob=,
1104       AssertPathIsDirectory=, AssertPathIsSymbolicLink=,
1105       AssertPathIsMountPoint=, AssertPathIsReadWrite=,
1106       AssertDirectoryNotEmpty=, AssertFileNotEmpty=, AssertFileIsExecutable=,
1107       AssertUser=, AssertGroup=, AssertControlGroupController=
1108           Similar to the ConditionArchitecture=, ConditionVirtualization=,
1109           ..., condition settings described above, these settings add
1110           assertion checks to the start-up of the unit. However, unlike the
1111           conditions settings, any assertion setting that is not met results
1112           in failure of the start job (which means this is logged loudly).
1113           Note that hitting a configured assertion does not cause the unit to
1114           enter the "failed" state (or in fact result in any state change of
1115           the unit), it affects only the job queued for it. Use assertion
1116           expressions for units that cannot operate when specific
1117           requirements are not met, and when this is something the
1118           administrator or user should look into.
1119

MAPPING OF UNIT PROPERTIES TO THEIR INVERSES

1121       Unit settings that create a relationship with a second unit usually
1122       show up in properties of both units, for example in systemctl show
1123       output. In some cases the name of the property is the same as the name
1124       of the configuration setting, but not always. This table lists the
1125       properties that are shown on two units which are connected through some
1126       dependency, and shows which property on "source" unit corresponds to
1127       which property on the "target" unit.
1128
1129       Table 3.  Forward and reverse unit properties
1130       ┌──────────────────────┬───────────────────────┬─────────────────────────────────┐
1131"Forward"             "Reverse"             Where used                      
1132property              property              │                                 │
1133       ├──────────────────────┼───────────────────────┼─────────────────────────────────┤
1134Before=After=                │                                 │
1135       ├──────────────────────┼───────────────────────┤ [Unit] section                  │
1136After=Before=               │                                 │
1137       ├──────────────────────┼───────────────────────┼─────────────────┬───────────────┤
1138Requires=RequiredBy=           │ [Unit] section  │ [Install]     │
1139       │                      │                       │                 │ section       │
1140       ├──────────────────────┼───────────────────────┼─────────────────┼───────────────┤
1141Wants=WantedBy=             │ [Unit] section  │ [Install]     │
1142       │                      │                       │                 │ section       │
1143       ├──────────────────────┼───────────────────────┼─────────────────┼───────────────┤
1144PartOf=ConsistsOf=           │ [Unit] section  │ an automatic  │
1145       │                      │                       │                 │ property      │
1146       ├──────────────────────┼───────────────────────┼─────────────────┼───────────────┤
1147BindsTo=BoundBy=              │ [Unit] section  │ an automatic  │
1148       │                      │                       │                 │ property      │
1149       ├──────────────────────┼───────────────────────┼─────────────────┼───────────────┤
1150Requisite=RequisiteOf=          │ [Unit] section  │ an automatic  │
1151       │                      │                       │                 │ property      │
1152       ├──────────────────────┼───────────────────────┼─────────────────┴───────────────┤
1153Triggers=TriggeredBy=          │ Automatic properties, see notes │
1154       │                      │                       │ below                           │
1155       ├──────────────────────┼───────────────────────┼─────────────────┬───────────────┤
1156Conflicts=ConflictedBy=         │ [Unit] section  │ an automatic  │
1157       │                      │                       │                 │ property      │
1158       ├──────────────────────┼───────────────────────┼─────────────────┴───────────────┤
1159PropagatesReloadTo=ReloadPropagatedFrom= │                                 │
1160       ├──────────────────────┼───────────────────────┤ [Unit] section                  │
1161ReloadPropagatedFrom=PropagatesReloadTo=   │                                 │
1162       ├──────────────────────┼───────────────────────┼─────────────────┬───────────────┤
1163Following=            │ n/a                   │ An automatic    │               │
1164       │                      │                       │ property        │               │
1165       └──────────────────────┴───────────────────────┴─────────────────┴───────────────┘
1166
1167       Note: WantedBy= and RequiredBy= are used in the [Install] section to
1168       create symlinks in .wants/ and .requires/ directories. They cannot be
1169       used directly as a unit configuration setting.
1170
1171       Note: ConsistsOf=, BoundBy=, RequisiteOf=, ConflictedBy= are created
1172       implicitly along with their reverses and cannot be specified directly.
1173
1174       Note: Triggers= is created implicitly between a socket, path unit, or
1175       an automount unit, and the unit they activate. By default a unit with
1176       the same name is triggered, but this can be overridden using Sockets=,
1177       Service=, and Unit= settings. See systemd.service(5),
1178       systemd.socket(5), systemd.path(5), and systemd.automount(5) for
1179       details.  TriggeredBy= is created implicitly on the triggered unit.
1180
1181       Note: Following= is used to group device aliases and points to the
1182       "primary" device unit that systemd is using to track device state,
1183       usually corresponding to a sysfs path. It does not show up in the
1184       "target" unit.
1185

[INSTALL] SECTION OPTIONS

1187       Unit files may include an "[Install]" section, which carries
1188       installation information for the unit. This section is not interpreted
1189       by systemd(1) during runtime; it is used by the enable and disable
1190       commands of the systemctl(1) tool during installation of a unit.
1191
1192       Alias=
1193           A space-separated list of additional names this unit shall be
1194           installed under. The names listed here must have the same suffix
1195           (i.e. type) as the unit filename. This option may be specified more
1196           than once, in which case all listed names are used. At installation
1197           time, systemctl enable will create symlinks from these names to the
1198           unit filename. Note that not all unit types support such alias
1199           names, and this setting is not supported for them. Specifically,
1200           mount, slice, swap, and automount units do not support aliasing.
1201
1202       WantedBy=, RequiredBy=
1203           This option may be used more than once, or a space-separated list
1204           of unit names may be given. A symbolic link is created in the
1205           .wants/ or .requires/ directory of each of the listed units when
1206           this unit is installed by systemctl enable. This has the effect
1207           that a dependency of type Wants= or Requires= is added from the
1208           listed unit to the current unit. The primary result is that the
1209           current unit will be started when the listed unit is started. See
1210           the description of Wants= and Requires= in the [Unit] section for
1211           details.
1212
1213           WantedBy=foo.service in a service bar.service is mostly equivalent
1214           to Alias=foo.service.wants/bar.service in the same file. In case of
1215           template units, systemctl enable must be called with an instance
1216           name, and this instance will be added to the .wants/ or .requires/
1217           list of the listed unit. E.g.  WantedBy=getty.target in a service
1218           getty@.service will result in systemctl enable getty@tty2.service
1219           creating a getty.target.wants/getty@tty2.service link to
1220           getty@.service.
1221
1222       Also=
1223           Additional units to install/deinstall when this unit is
1224           installed/deinstalled. If the user requests
1225           installation/deinstallation of a unit with this option configured,
1226           systemctl enable and systemctl disable will automatically
1227           install/uninstall units listed in this option as well.
1228
1229           This option may be used more than once, or a space-separated list
1230           of unit names may be given.
1231
1232       DefaultInstance=
1233           In template unit files, this specifies for which instance the unit
1234           shall be enabled if the template is enabled without any explicitly
1235           set instance. This option has no effect in non-template unit files.
1236           The specified string must be usable as instance identifier.
1237
1238       The following specifiers are interpreted in the Install section: %n,
1239       %N, %p, %i, %j, %g, %G, %U, %u, %m, %H, %b, %v. For their meaning see
1240       the next section.
1241

SPECIFIERS

1243       Many settings resolve specifiers which may be used to write generic
1244       unit files referring to runtime or unit parameters that are replaced
1245       when the unit files are loaded. Specifiers must be known and resolvable
1246       for the setting to be valid. The following specifiers are understood:
1247
1248       Table 4. Specifiers available in unit files
1249       ┌──────────┬─────────────────────┬─────────────────────┐
1250Specifier Meaning             Details             
1251       ├──────────┼─────────────────────┼─────────────────────┤
1252       │"%b"      │ Boot ID             │ The boot ID of the  │
1253       │          │                     │ running system,     │
1254       │          │                     │ formatted as        │
1255       │          │                     │ string. See         │
1256       │          │                     │ random(4) for more  │
1257       │          │                     │ information.        │
1258       ├──────────┼─────────────────────┼─────────────────────┤
1259       │"%C"      │ Cache directory     │ This is either      │
1260       │          │ root                │ /var/cache (for the │
1261       │          │                     │ system manager) or  │
1262       │          │                     │ the path            │
1263       │          │                     │ "$XDG_CACHE_HOME"   │
1264       │          │                     │ resolves to (for    │
1265       │          │                     │ user managers).     │
1266       ├──────────┼─────────────────────┼─────────────────────┤
1267       │"%E"      │ Configuration       │ This is either /etc │
1268       │          │ directory root      │ (for the system     │
1269       │          │                     │ manager) or the     │
1270       │          │                     │ path                │
1271       │          │                     │ "$XDG_CONFIG_HOME"  │
1272       │          │                     │ resolves to (for    │
1273       │          │                     │ user managers).     │
1274       ├──────────┼─────────────────────┼─────────────────────┤
1275       │"%f"      │ Unescaped filename  │ This is either the  │
1276       │          │                     │ unescaped instance  │
1277       │          │                     │ name (if            │
1278       │          │                     │ applicable) with /  │
1279       │          │                     │ prepended (if       │
1280       │          │                     │ applicable), or the │
1281       │          │                     │ unescaped prefix    │
1282       │          │                     │ name prepended with │
1283       │          │                     │ /. This implements  │
1284       │          │                     │ unescaping          │
1285       │          │                     │ according to the    │
1286       │          │                     │ rules for escaping  │
1287       │          │                     │ absolute file       │
1288       │          │                     │ system paths        │
1289       │          │                     │ discussed above.    │
1290       ├──────────┼─────────────────────┼─────────────────────┤
1291       │"%h"      │ User home directory │ This is the home    │
1292       │          │                     │ directory of the    │
1293       │          │                     │ user running the
1294       │          │                     │ service manager
1295       │          │                     │ instance. In case   │
1296       │          │                     │ of the system       │
1297       │          │                     │ manager this        │
1298       │          │                     │ resolves to         │
1299       │          │                     │ "/root".            │
1300       │          │                     │                     │
1301       │          │                     │ Note that this      │
1302       │          │                     │ setting is not
1303       │          │                     │ influenced by the   │
1304       │          │                     │ User= setting       │
1305       │          │                     │ configurable in the │
1306       │          │                     │ [Service] section   │
1307       │          │                     │ of the service      │
1308       │          │                     │ unit.               │
1309       ├──────────┼─────────────────────┼─────────────────────┤
1310       │"%H"      │ Host name           │ The hostname of the │
1311       │          │                     │ running system at   │
1312       │          │                     │ the point in time   │
1313       │          │                     │ the unit            │
1314       │          │                     │ configuration is    │
1315       │          │                     │ loaded.             │
1316       ├──────────┼─────────────────────┼─────────────────────┤
1317       │"%i"      │ Instance name       │ For instantiated    │
1318       │          │                     │ units this is the   │
1319       │          │                     │ string between the  │
1320       │          │                     │ first "@" character │
1321       │          │                     │ and the type        │
1322       │          │                     │ suffix. Empty for   │
1323       │          │                     │ non-instantiated    │
1324       │          │                     │ units.              │
1325       ├──────────┼─────────────────────┼─────────────────────┤
1326       │"%I"      │ Unescaped instance  │ Same as "%i", but   │
1327       │          │ name                │ with escaping       │
1328       │          │                     │ undone.             │
1329       ├──────────┼─────────────────────┼─────────────────────┤
1330       │"%j"      │ Final component of  │ This is the string  │
1331       │          │ the prefix          │ between the last    │
1332       │          │                     │ "-" and the end of  │
1333       │          │                     │ the prefix name. If │
1334       │          │                     │ there is no "-",    │
1335       │          │                     │ this is the same as │
1336       │          │                     │ "%p".               │
1337       ├──────────┼─────────────────────┼─────────────────────┤
1338       │"%J"      │ Unescaped final     │ Same as "%j", but   │
1339       │          │ component of the    │ with escaping       │
1340       │          │ prefix              │ undone.             │
1341       ├──────────┼─────────────────────┼─────────────────────┤
1342       │"%L"      │ Log directory root  │ This is either      │
1343       │          │                     │ /var/log (for the   │
1344       │          │                     │ system manager) or  │
1345       │          │                     │ the path            │
1346       │          │                     │ "$XDG_CONFIG_HOME"  │
1347       │          │                     │ resolves to with    │
1348       │          │                     │ /log appended (for  │
1349       │          │                     │ user managers).     │
1350       ├──────────┼─────────────────────┼─────────────────────┤
1351       │"%m"      │ Machine ID          │ The machine ID of   │
1352       │          │                     │ the running system, │
1353       │          │                     │ formatted as        │
1354       │          │                     │ string. See         │
1355       │          │                     │ machine-id(5) for   │
1356       │          │                     │ more information.   │
1357       ├──────────┼─────────────────────┼─────────────────────┤
1358       │"%n"      │ Full unit name      │                     │
1359       ├──────────┼─────────────────────┼─────────────────────┤
1360       │"%N"      │ Full unit name      │ Same as "%n", but   │
1361       │          │                     │ with the type       │
1362       │          │                     │ suffix removed.     │
1363       ├──────────┼─────────────────────┼─────────────────────┤
1364       │"%p"      │ Prefix name         │ For instantiated    │
1365       │          │                     │ units, this refers  │
1366       │          │                     │ to the string       │
1367       │          │                     │ before the first    │
1368       │          │                     │ "@" character of    │
1369       │          │                     │ the unit name. For  │
1370       │          │                     │ non-instantiated    │
1371       │          │                     │ units, same as      │
1372       │          │                     │ "%N".               │
1373       ├──────────┼─────────────────────┼─────────────────────┤
1374       │"%P"      │ Unescaped prefix    │ Same as "%p", but   │
1375       │          │ name                │ with escaping       │
1376       │          │                     │ undone.             │
1377       ├──────────┼─────────────────────┼─────────────────────┤
1378       │"%s"      │ User shell          │ This is the shell   │
1379       │          │                     │ of the user running │
1380       │          │                     │ the service manager │
1381       │          │                     │ instance. In case   │
1382       │          │                     │ of the system       │
1383       │          │                     │ manager this        │
1384       │          │                     │ resolves to         │
1385       │          │                     │ "/bin/sh".          │
1386       ├──────────┼─────────────────────┼─────────────────────┤
1387       │"%S"      │ State directory     │ This is either      │
1388       │          │ root                │ /var/lib (for the   │
1389       │          │                     │ system manager) or  │
1390       │          │                     │ the path            │
1391       │          │                     │ "$XDG_CONFIG_HOME"  │
1392       │          │                     │ resolves to (for    │
1393       │          │                     │ user managers).     │
1394       ├──────────┼─────────────────────┼─────────────────────┤
1395       │"%t"      │ Runtime directory   │ This is either /run │
1396       │          │ root                │ (for the system     │
1397       │          │                     │ manager) or the     │
1398       │          │                     │ path                │
1399       │          │                     │ "$XDG_RUNTIME_DIR"  │
1400       │          │                     │ resolves to (for    │
1401       │          │                     │ user managers).     │
1402       ├──────────┼─────────────────────┼─────────────────────┤
1403       │"%T"      │ Directory for       │ This is either /tmp │
1404       │          │ temporary files     │ or the path         │
1405       │          │                     │ "$TMPDIR", "$TEMP"  │
1406       │          │                     │ or "$TMP" are set   │
1407       │          │                     │ to.                 │
1408       ├──────────┼─────────────────────┼─────────────────────┤
1409       │"%g"      │ User group          │ This is the name of │
1410       │          │                     │ the group running   │
1411       │          │                     │ the service manager │
1412       │          │                     │ instance. In case   │
1413       │          │                     │ of the system       │
1414       │          │                     │ manager this        │
1415       │          │                     │ resolves to "root". │
1416       ├──────────┼─────────────────────┼─────────────────────┤
1417       │"%G"      │ User GID            │ This is the numeric │
1418       │          │                     │ GID of the user     │
1419       │          │                     │ running the service │
1420       │          │                     │ manager instance.   │
1421       │          │                     │ In case of the      │
1422       │          │                     │ system manager this │
1423       │          │                     │ resolves to "0".    │
1424       ├──────────┼─────────────────────┼─────────────────────┤
1425       │"%u"      │ User name           │ This is the name of │
1426       │          │                     │ the user running
1427       │          │                     │ the service manager
1428       │          │                     │ instance. In case   │
1429       │          │                     │ of the system       │
1430       │          │                     │ manager this        │
1431       │          │                     │ resolves to "root". │
1432       │          │                     │                     │
1433       │          │                     │ Note that this      │
1434       │          │                     │ setting is not
1435       │          │                     │ influenced by the   │
1436       │          │                     │ User= setting       │
1437       │          │                     │ configurable in the │
1438       │          │                     │ [Service] section   │
1439       │          │                     │ of the service      │
1440       │          │                     │ unit.               │
1441       ├──────────┼─────────────────────┼─────────────────────┤
1442       │"%U"      │ User UID            │ This is the numeric │
1443       │          │                     │ UID of the user
1444       │          │                     │ running the service
1445       │          │                     │ manager instance.   │
1446       │          │                     │ In case of the      │
1447       │          │                     │ system manager this │
1448       │          │                     │ resolves to "0".    │
1449       │          │                     │                     │
1450       │          │                     │ Note that this      │
1451       │          │                     │ setting is not
1452       │          │                     │ influenced by the   │
1453       │          │                     │ User= setting       │
1454       │          │                     │ configurable in the │
1455       │          │                     │ [Service] section   │
1456       │          │                     │ of the service      │
1457       │          │                     │ unit.               │
1458       ├──────────┼─────────────────────┼─────────────────────┤
1459       │"%v"      │ Kernel release      │ Identical to uname  
1460       │          │                     │ -r output           │
1461       ├──────────┼─────────────────────┼─────────────────────┤
1462       │"%V"      │ Directory for       │ This is either      │
1463       │          │ larger and          │ /var/tmp or the     │
1464       │          │ persistent          │ path "$TMPDIR",     │
1465       │          │ temporary files     │ "$TEMP" or "$TMP"   │
1466       │          │                     │ are set to.         │
1467       ├──────────┼─────────────────────┼─────────────────────┤
1468       │"%%"      │ Single percent sign │ Use "%%" in place   │
1469       │          │                     │ of "%" to specify a │
1470       │          │                     │ single percent      │
1471       │          │                     │ sign.               │
1472       └──────────┴─────────────────────┴─────────────────────┘
1473

EXAMPLES

1475       Example 1. Allowing units to be enabled
1476
1477       The following snippet (highlighted) allows a unit (e.g.  foo.service)
1478       to be enabled via systemctl enable:
1479
1480           [Unit]
1481           Description=Foo
1482
1483           [Service]
1484           ExecStart=/usr/sbin/foo-daemon
1485
1486           [Install]
1487           WantedBy=multi-user.target
1488
1489       After running systemctl enable, a symlink
1490       /etc/systemd/system/multi-user.target.wants/foo.service linking to the
1491       actual unit will be created. It tells systemd to pull in the unit when
1492       starting multi-user.target. The inverse systemctl disable will remove
1493       that symlink again.
1494
1495       Example 2. Overriding vendor settings
1496
1497       There are two methods of overriding vendor settings in unit files:
1498       copying the unit file from /usr/lib/systemd/system to
1499       /etc/systemd/system and modifying the chosen settings. Alternatively,
1500       one can create a directory named unit.d/ within /etc/systemd/system and
1501       place a drop-in file name.conf there that only changes the specific
1502       settings one is interested in. Note that multiple such drop-in files
1503       are read if present, processed in lexicographic order of their
1504       filename.
1505
1506       The advantage of the first method is that one easily overrides the
1507       complete unit, the vendor unit is not parsed at all anymore. It has the
1508       disadvantage that improvements to the unit file by the vendor are not
1509       automatically incorporated on updates.
1510
1511       The advantage of the second method is that one only overrides the
1512       settings one specifically wants, where updates to the unit by the
1513       vendor automatically apply. This has the disadvantage that some future
1514       updates by the vendor might be incompatible with the local changes.
1515
1516       This also applies for user instances of systemd, but with different
1517       locations for the unit files. See the section on unit load paths for
1518       further details.
1519
1520       Suppose there is a vendor-supplied unit
1521       /usr/lib/systemd/system/httpd.service with the following contents:
1522
1523           [Unit]
1524           Description=Some HTTP server
1525           After=remote-fs.target sqldb.service
1526           Requires=sqldb.service
1527           AssertPathExists=/srv/webserver
1528
1529           [Service]
1530           Type=notify
1531           ExecStart=/usr/sbin/some-fancy-httpd-server
1532           Nice=5
1533
1534           [Install]
1535           WantedBy=multi-user.target
1536
1537       Now one wants to change some settings as an administrator: firstly, in
1538       the local setup, /srv/webserver might not exist, because the HTTP
1539       server is configured to use /srv/www instead. Secondly, the local
1540       configuration makes the HTTP server also depend on a memory cache
1541       service, memcached.service, that should be pulled in (Requires=) and
1542       also be ordered appropriately (After=). Thirdly, in order to harden the
1543       service a bit more, the administrator would like to set the PrivateTmp=
1544       setting (see systemd.exec(5) for details). And lastly, the
1545       administrator would like to reset the niceness of the service to its
1546       default value of 0.
1547
1548       The first possibility is to copy the unit file to
1549       /etc/systemd/system/httpd.service and change the chosen settings:
1550
1551           [Unit]
1552           Description=Some HTTP server
1553           After=remote-fs.target sqldb.service memcached.service
1554           Requires=sqldb.service memcached.service
1555           AssertPathExists=/srv/www
1556
1557           [Service]
1558           Type=notify
1559           ExecStart=/usr/sbin/some-fancy-httpd-server
1560           Nice=0
1561           PrivateTmp=yes
1562
1563           [Install]
1564           WantedBy=multi-user.target
1565
1566       Alternatively, the administrator could create a drop-in file
1567       /etc/systemd/system/httpd.service.d/local.conf with the following
1568       contents:
1569
1570           [Unit]
1571           After=memcached.service
1572           Requires=memcached.service
1573           # Reset all assertions and then re-add the condition we want
1574           AssertPathExists=
1575           AssertPathExists=/srv/www
1576
1577           [Service]
1578           Nice=0
1579           PrivateTmp=yes
1580
1581       Note that for drop-in files, if one wants to remove entries from a
1582       setting that is parsed as a list (and is not a dependency), such as
1583       AssertPathExists= (or e.g.  ExecStart= in service units), one needs to
1584       first clear the list before re-adding all entries except the one that
1585       is to be removed. Dependencies (After=, etc.) cannot be reset to an
1586       empty list, so dependencies can only be added in drop-ins. If you want
1587       to remove dependencies, you have to override the entire unit.
1588

SEE ALSO

1590       systemd(1), systemctl(1), systemd-system.conf(5), systemd.special(7),
1591       systemd.service(5), systemd.socket(5), systemd.device(5),
1592       systemd.mount(5), systemd.automount(5), systemd.swap(5),
1593       systemd.target(5), systemd.path(5), systemd.timer(5), systemd.scope(5),
1594       systemd.slice(5), systemd.time(7), systemd-analyze(1), capabilities(7),
1595       systemd.directives(7), uname(1)
1596

NOTES

1598        1. Interface Stability Promise
1599           https://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise
1600
1601
1602
1603systemd 245                                                    SYSTEMD.UNIT(5)
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