chiark / gitweb /
service: make the fsck pass no configurable
[elogind.git] / man / systemd.service.xml
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3 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
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9   Copyright 2010 Lennart Poettering
10
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24
25 <refentry id="systemd.service">
26         <refentryinfo>
27                 <title>systemd.service</title>
28                 <productname>systemd</productname>
29
30                 <authorgroup>
31                         <author>
32                                 <contrib>Developer</contrib>
33                                 <firstname>Lennart</firstname>
34                                 <surname>Poettering</surname>
35                                 <email>lennart@poettering.net</email>
36                         </author>
37                 </authorgroup>
38         </refentryinfo>
39
40         <refmeta>
41                 <refentrytitle>systemd.service</refentrytitle>
42                 <manvolnum>5</manvolnum>
43         </refmeta>
44
45         <refnamediv>
46                 <refname>systemd.service</refname>
47                 <refpurpose>systemd service configuration files</refpurpose>
48         </refnamediv>
49
50         <refsynopsisdiv>
51                 <para><filename>systemd.service</filename></para>
52         </refsynopsisdiv>
53
54         <refsect1>
55                 <title>Description</title>
56
57                 <para>A unit configuration file whose name ends in
58                 <filename>.service</filename> encodes information
59                 about a process controlled and supervised by
60                 systemd.</para>
61
62                 <para>This man page lists the configuration options
63                 specific to this unit type. See
64                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>
65                 for the common options of all unit configuration
66                 files. The common configuration items are configured
67                 in the generic <literal>[Unit]</literal> and
68                 <literal>[Install]</literal> sections. The service
69                 specific configuration options are configured in the
70                 <literal>[Service]</literal> section.</para>
71
72                 <para>Additional options are listed in
73                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
74                 which define the execution environment the commands
75                 are executed in.</para>
76
77                 <para>Unless <varname>DefaultDependencies=</varname>
78                 is set to <option>false</option>, service units will
79                 implicitly have dependencies of type
80                 <varname>Requires=</varname> and
81                 <varname>After=</varname> on
82                 <filename>basic.target</filename> as well as
83                 dependencies of type <varname>Conflicts=</varname> and
84                 <varname>Before=</varname> on
85                 <filename>shutdown.target</filename>. These ensure
86                 that normal service units pull in basic system
87                 initialization, and are terminated cleanly prior to
88                 system shutdown. Only services involved with early
89                 boot or late system shutdown should disable this
90                 option.</para>
91
92                 <para>If a service is requested under a certain name
93                 but no unit configuration file is found, systemd looks
94                 for a SysV init script by the same name (with the
95                 <filename>.service</filename> suffix removed) and
96                 dynamically creates a service unit from that
97                 script. This is useful for compatibility with
98                 SysV.</para>
99         </refsect1>
100
101         <refsect1>
102                 <title>Options</title>
103
104                 <para>Service files must include a
105                 <literal>[Service]</literal> section, which carries
106                 information about the service and the process it
107                 supervises. A number of options that may be used in
108                 this section are shared with other unit types. These
109                 options are documented in
110                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
111                 options specific to the <literal>[Service]</literal>
112                 section of service units are the following:</para>
113
114                 <variablelist>
115                         <varlistentry>
116                                 <term><varname>Type=</varname></term>
117
118                                 <listitem><para>Configures the process
119                                 start-up type for this service
120                                 unit. One of <option>simple</option>,
121                                 <option>forking</option>,
122                                 <option>oneshot</option>,
123                                 <option>dbus</option>,
124                                 <option>notify</option> or
125                                 <option>idle</option>.</para>
126
127                                 <para>If set to
128                                 <option>simple</option> (the default
129                                 value if <varname>BusName=</varname>
130                                 is not specified) it is expected that
131                                 the process configured with
132                                 <varname>ExecStart=</varname> is the
133                                 main process of the service. In this
134                                 mode, if the process offers
135                                 functionality to other processes on
136                                 the system its communication channels
137                                 should be installed before the daemon
138                                 is started up (e.g. sockets set up by
139                                 systemd, via socket activation), as
140                                 systemd will immediately proceed
141                                 starting follow-up units.</para>
142
143                                 <para>If set to
144                                 <option>forking</option> it is
145                                 expected that the process configured
146                                 with <varname>ExecStart=</varname>
147                                 will call <function>fork()</function>
148                                 as part of its start-up. The parent process is
149                                 expected to exit when start-up is
150                                 complete and all communication
151                                 channels set up. The child continues
152                                 to run as the main daemon
153                                 process. This is the behaviour of
154                                 traditional UNIX daemons. If this
155                                 setting is used, it is recommended to
156                                 also use the
157                                 <varname>PIDFile=</varname> option, so
158                                 that systemd can identify the main
159                                 process of the daemon. systemd will
160                                 proceed starting follow-up units as
161                                 soon as the parent process
162                                 exits.</para>
163
164                                 <para>Behaviour of
165                                 <option>oneshot</option> is similar
166                                 to <option>simple</option>, however
167                                 it is expected that the process has to
168                                 exit before systemd starts follow-up
169                                 units. <varname>RemainAfterExit=</varname>
170                                 is particularly useful for this type
171                                 of service.</para>
172
173                                 <para>Behaviour of
174                                 <option>dbus</option> is similar to
175                                 <option>simple</option>, however it is
176                                 expected that the daemon acquires a
177                                 name on the D-Bus bus, as configured
178                                 by
179                                 <varname>BusName=</varname>. systemd
180                                 will proceed starting follow-up units
181                                 after the D-Bus bus name has been
182                                 acquired. Service units with this
183                                 option configured implicitly gain
184                                 dependencies on the
185                                 <filename>dbus.socket</filename>
186                                 unit. This type is the default if
187                                 <varname>BusName=</varname> is
188                                 specified.</para>
189
190                                 <para>Behaviour of
191                                 <option>notify</option> is similar to
192                                 <option>simple</option>, however it is
193                                 expected that the daemon sends a
194                                 notification message via
195                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
196                                 or an equivalent call when it finished
197                                 starting up. systemd will proceed
198                                 starting follow-up units after this
199                                 notification message has been sent. If
200                                 this option is used
201                                 <varname>NotifyAccess=</varname> (see
202                                 below) should be set to open access to
203                                 the notification socket provided by
204                                 systemd. If
205                                 <varname>NotifyAccess=</varname> is
206                                 not set, it will be implicitly set to
207                                 <option>main</option>.</para>
208
209                                 <para>Behaviour of
210                                 <option>idle</option> is very similar
211                                 to <option>simple</option>, however
212                                 actual execution of a the service
213                                 binary is delayed until all jobs are
214                                 dispatched. This may be used to avoid
215                                 interleaving of output of shell
216                                 services with the status output on the
217                                 console.</para>
218                                 </listitem>
219                         </varlistentry>
220
221                         <varlistentry>
222                                 <term><varname>RemainAfterExit=</varname></term>
223
224                                 <listitem><para>Takes a boolean value
225                                 that specifies whether the service
226                                 shall be considered active even when
227                                 all its processes exited. Defaults to
228                                 <option>no</option>.</para>
229                                 </listitem>
230                         </varlistentry>
231
232                         <varlistentry>
233                                 <term><varname>GuessMainPID=</varname></term>
234
235                                 <listitem><para>Takes a boolean value
236                                 that specifies whether systemd should
237                                 try to guess the main PID of a service
238                                 should if it cannot be determined
239                                 reliably. This option is ignored
240                                 unless <option>Type=forking</option>
241                                 is set and <option>PIDFile=</option>
242                                 is unset because for the other types
243                                 or with an explicitly configured PID
244                                 file the main PID is always known. The
245                                 guessing algorithm might come to
246                                 incorrect conclusions if a daemon
247                                 consists of more than one process. If
248                                 the main PID cannot be determined
249                                 failure detection and automatic
250                                 restarting of a service will not work
251                                 reliably. Defaults to
252                                 <option>yes</option>.</para>
253                                 </listitem>
254                         </varlistentry>
255
256                         <varlistentry>
257                                 <term><varname>PIDFile=</varname></term>
258
259                                 <listitem><para>Takes an absolute file
260                                 name pointing to the PID file of this
261                                 daemon. Use of this option is
262                                 recommended for services where
263                                 <varname>Type=</varname> is set to
264                                 <option>forking</option>. systemd will
265                                 read the PID of the main process of
266                                 the daemon after start-up of the
267                                 service. systemd will not write to the
268                                 file configured here.</para>
269                                 </listitem>
270                         </varlistentry>
271
272                         <varlistentry>
273                                 <term><varname>BusName=</varname></term>
274
275                                 <listitem><para>Takes a D-Bus bus
276                                 name, where this service is reachable
277                                 as. This option is mandatory for
278                                 services where
279                                 <varname>Type=</varname> is set to
280                                 <option>dbus</option>, but its use
281                                 is otherwise recommended as well if
282                                 the process takes a name on the D-Bus
283                                 bus.</para>
284                                 </listitem>
285                         </varlistentry>
286
287                         <varlistentry>
288                                 <term><varname>ExecStart=</varname></term>
289                                 <listitem><para>Takes a command line
290                                 that is executed when this service
291                                 shall be started up. The first token
292                                 of the command line must be an
293                                 absolute file name, then followed by
294                                 arguments for the process. It is
295                                 mandatory to set this option for all
296                                 services. This option may not be
297                                 specified more than once, except when
298                                 <varname>Type=oneshot</varname> is
299                                 used in which case more than one
300                                 <varname>ExecStart=</varname> line is
301                                 accepted which are then invoked one by
302                                 one, sequentially in the order they
303                                 appear in the unit file.</para>
304
305                                 <para>Optionally, if the absolute file
306                                 name is prefixed with
307                                 <literal>@</literal>, the second token
308                                 will be passed as
309                                 <literal>argv[0]</literal> to the
310                                 executed process, followed by the
311                                 further arguments specified. If the
312                                 first token is prefixed with
313                                 <literal>-</literal> an exit code of
314                                 the command normally considered a
315                                 failure (i.e. non-zero exit status or
316                                 abnormal exit due to signal) is ignored
317                                 and considered success. If both
318                                 <literal>-</literal> and
319                                 <literal>@</literal> are used for the
320                                 same command the former must precede
321                                 the latter. Unless
322                                 <varname>Type=forking</varname> is
323                                 set, the process started via this
324                                 command line will be considered the
325                                 main process of the daemon. The
326                                 command line accepts % specifiers as
327                                 described in
328                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
329
330                                 <para>On top of that basic environment
331                                 variable substitution is
332                                 supported. Use
333                                 <literal>${FOO}</literal> as part of a
334                                 word, or as word of its own on the
335                                 command line, in which case it will be
336                                 replaced by the value of the
337                                 environment variable including all
338                                 whitespace it contains, resulting in a
339                                 single argument.  Use
340                                 <literal>$FOO</literal> as a separate
341                                 word on the command line, in which
342                                 case it will be replaced by the value
343                                 of the environment variable split up
344                                 at whitespace, resulting in no or more
345                                 arguments. Note that the first
346                                 argument (i.e. the program to execute)
347                                 may not be a variable, and must be a
348                                 literal and absolute path
349                                 name.</para></listitem>
350                         </varlistentry>
351
352                         <varlistentry>
353                                 <term><varname>ExecStartPre=</varname></term>
354                                 <term><varname>ExecStartPost=</varname></term>
355                                 <listitem><para>Additional commands
356                                 that are executed before (resp. after)
357                                 the command in
358                                 <varname>ExecStart=</varname>. Multiple
359                                 command lines may be concatenated in a
360                                 single directive, by separating them
361                                 by semicolons (these semicolons must
362                                 be passed as separate words). In that
363                                 case, the commands are executed one
364                                 after the other,
365                                 serially. Alternatively, these
366                                 directives may be specified more than
367                                 once with the same effect. However,
368                                 the latter syntax is not recommended
369                                 for compatibility with parsers
370                                 suitable for XDG
371                                 <filename>.desktop</filename> files.
372                                 Use of these settings is
373                                 optional. Specifier and environment
374                                 variable substitution is
375                                 supported.</para></listitem>
376                         </varlistentry>
377
378                         <varlistentry>
379                                 <term><varname>ExecReload=</varname></term>
380                                 <listitem><para>Commands to execute to
381                                 trigger a configuration reload in the
382                                 service. This argument takes multiple
383                                 command lines, following the same
384                                 scheme as pointed out for
385                                 <varname>ExecStartPre=</varname>
386                                 above. Use of this setting is
387                                 optional. Specifier and environment
388                                 variable substitution is supported
389                                 here following the same scheme as for
390                                 <varname>ExecStart=</varname>. One
391                                 special environment variable is set:
392                                 if known <literal>$MAINPID</literal> is
393                                 set to the main process of the
394                                 daemon, and may be used for command
395                                 lines like the following:
396                                 <command>/bin/kill -HUP
397                                 $MAINPID</command>.</para></listitem>
398                         </varlistentry>
399
400                         <varlistentry>
401                                 <term><varname>ExecStop=</varname></term>
402                                 <listitem><para>Commands to execute to
403                                 stop the service started via
404                                 <varname>ExecStart=</varname>. This
405                                 argument takes multiple command lines,
406                                 following the same scheme as pointed
407                                 out for
408                                 <varname>ExecStartPre=</varname>
409                                 above. Use of this setting is
410                                 optional. All processes remaining for
411                                 a service after the commands
412                                 configured in this option are run are
413                                 terminated according to the
414                                 <varname>KillMode=</varname> setting
415                                 (see below). If this option is not
416                                 specified the process is terminated
417                                 right-away when service stop is
418                                 requested. Specifier and environment
419                                 variable substitution is supported
420                                 (including
421                                 <literal>$MAINPID</literal>, see
422                                 above).</para></listitem>
423                         </varlistentry>
424
425                         <varlistentry>
426                                 <term><varname>ExecStopPost=</varname></term>
427                                 <listitem><para>Additional commands
428                                 that are executed after the service
429                                 was stopped using the commands
430                                 configured in
431                                 <varname>ExecStop=</varname>. This
432                                 argument takes multiple command lines,
433                                 following the same scheme as pointed
434                                 out for
435                                 <varname>ExecStartPre</varname>. Use
436                                 of these settings is
437                                 optional. Specifier and environment
438                                 variable substitution is
439                                 supported.</para></listitem>
440                         </varlistentry>
441
442                         <varlistentry>
443                                 <term><varname>RestartSec=</varname></term>
444                                 <listitem><para>Configures the time to
445                                 sleep before restarting a service (as
446                                 configured with
447                                 <varname>Restart=</varname>). Takes a
448                                 unit-less value in seconds, or a time
449                                 span value such as "5min
450                                 20s". Defaults to
451                                 100ms.</para></listitem>
452                         </varlistentry>
453
454                         <varlistentry>
455                                 <term><varname>TimeoutSec=</varname></term>
456                                 <listitem><para>Configures the time to
457                                 wait for start-up and stop. If a
458                                 daemon service does not signal
459                                 start-up completion within the
460                                 configured time the service will be
461                                 considered failed and be shut down
462                                 again. If a service is asked to stop
463                                 but does not terminate in the
464                                 specified time it will be terminated
465                                 forcibly via SIGTERM, and after
466                                 another delay of this time with
467                                 SIGKILL. (See
468                                 <varname>KillMode=</varname>
469                                 below.) Takes a unit-less value in seconds, or a
470                                 time span value such as "5min
471                                 20s". Pass 0 to disable the timeout
472                                 logic. Defaults to
473                                 90s.</para></listitem>
474                         </varlistentry>
475
476                         <varlistentry>
477                                 <term><varname>WatchdogSec=</varname></term>
478                                 <listitem><para>Configures the
479                                 watchdog timeout for a service. This
480                                 is activated when the start-up is
481                                 completed. The service must call
482                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
483                                 regularly with "WATCHDOG=1". If the
484                                 time between two such calls is larger
485                                 than the configured time then the
486                                 service is placed in a failure
487                                 state. By setting
488                                 <varname>Restart=</varname>
489                                 to <option>on-failure</option> or
490                                 <option>always</option> the service
491                                 will be automatically restarted. The
492                                 time configured here will be passed to
493                                 the executed service process in the
494                                 <varname>WATCHDOG_USEC=</varname>
495                                 environment variable. If
496                                 this option is used
497                                 <varname>NotifyAccess=</varname> (see
498                                 below) should be set to open access to
499                                 the notification socket provided by
500                                 systemd. If
501                                 <varname>NotifyAccess=</varname> is not
502                                 set, it will be implicitly set to
503                                 <option>main</option>. Defaults to 0,
504                                 which disables this
505                                 feature.</para></listitem>
506                         </varlistentry>
507
508                         <varlistentry>
509                                 <term><varname>Restart=</varname></term>
510                                 <listitem><para>Configures whether the
511                                 main service process shall be
512                                 restarted when it exits. Takes one of
513                                 <option>no</option>,
514                                 <option>on-success</option>,
515                                 <option>on-failure</option>,
516                                 <option>on-abort</option> or
517                                 <option>always</option>. If set to
518                                 <option>no</option> (the default) the
519                                 service will not be restarted when it
520                                 exits. If set to
521                                 <option>on-success</option> it will be
522                                 restarted only when it exited cleanly,
523                                 i.e. terminated with an exit code of
524                                 0. If set to
525                                 <option>on-failure</option> it will be
526                                 restarted only when it exited with an
527                                 exit code not equalling 0, when
528                                 terminated by a signal, when an
529                                 operation times out or when the
530                                 configured watchdog timeout is
531                                 triggered. If set to
532                                 <option>on-abort</option> it will be
533                                 restarted only if it exits due to
534                                 reception of an uncaught signal. If
535                                 set to <option>always</option> the
536                                 service will be restarted regardless
537                                 whether it exited cleanly or not,
538                                 got terminated abnormally by a
539                                 signal or hit a timeout.</para></listitem>
540                         </varlistentry>
541
542                         <varlistentry>
543                                 <term><varname>PermissionsStartOnly=</varname></term>
544                                 <listitem><para>Takes a boolean
545                                 argument. If true, the permission
546                                 related execution options as
547                                 configured with
548                                 <varname>User=</varname> and similar
549                                 options (see
550                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
551                                 for more information) are only applied
552                                 to the process started with
553                                 <varname>ExecStart=</varname>, and not
554                                 to the various other
555                                 <varname>ExecStartPre=</varname>,
556                                 <varname>ExecStartPost=</varname>,
557                                 <varname>ExecReload=</varname>,
558                                 <varname>ExecStop=</varname>,
559                                 <varname>ExecStopPost=</varname>
560                                 commands. If false, the setting is
561                                 applied to all configured commands the
562                                 same way. Defaults to
563                                 false.</para></listitem>
564                         </varlistentry>
565
566                         <varlistentry>
567                                 <term><varname>RootDirectoryStartOnly=</varname></term>
568                                 <listitem><para>Takes a boolean
569                                 argument. If true, the root directory
570                                 as configured with the
571                                 <varname>RootDirectory=</varname>
572                                 option (see
573                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
574                                 for more information) is only applied
575                                 to the process started with
576                                 <varname>ExecStart=</varname>, and not
577                                 to the various other
578                                 <varname>ExecStartPre=</varname>,
579                                 <varname>ExecStartPost=</varname>,
580                                 <varname>ExecReload=</varname>,
581                                 <varname>ExecStop=</varname>,
582                                 <varname>ExecStopPost=</varname>
583                                 commands. If false, the setting is
584                                 applied to all configured commands the
585                                 same way. Defaults to
586                                 false.</para></listitem>
587                         </varlistentry>
588
589                         <varlistentry>
590                                 <term><varname>SysVStartPriority=</varname></term>
591                                 <listitem><para>Set the SysV start
592                                 priority to use to order this service
593                                 in relation to SysV services lacking
594                                 LSB headers. This option is only
595                                 necessary to fix ordering in relation
596                                 to legacy SysV services, that have no
597                                 ordering information encoded in the
598                                 script headers. As such it should only
599                                 be used as temporary compatibility
600                                 option, and not be used in new unit
601                                 files. Almost always it is a better
602                                 choice to add explicit ordering
603                                 directives via
604                                 <varname>After=</varname> or
605                                 <varname>Before=</varname>,
606                                 instead. For more details see
607                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
608                                 used, pass an integer value in the
609                                 range 0-99.</para></listitem>
610                         </varlistentry>
611
612                         <varlistentry>
613                                 <term><varname>KillMode=</varname></term>
614                                 <listitem><para>Specifies how
615                                 processes of this service shall be
616                                 killed. One of
617                                 <option>control-group</option>,
618                                 <option>process</option>,
619                                 <option>none</option>.</para>
620
621                                 <para>If set to
622                                 <option>control-group</option> all
623                                 remaining processes in the control
624                                 group of this service will be
625                                 terminated on service stop, after the
626                                 stop command (as configured with
627                                 <varname>ExecStop=</varname>) is
628                                 executed. If set to
629                                 <option>process</option> only the main
630                                 process itself is killed. If set to
631                                 <option>none</option> no process is
632                                 killed. In this case only the stop
633                                 command will be executed on service
634                                 stop, but no process be killed
635                                 otherwise. Processes remaining alive
636                                 after stop are left in their control
637                                 group and the control group continues
638                                 to exist after stop unless it is
639                                 empty. Defaults to
640                                 <option>control-group</option>.</para>
641
642                                 <para>Processes will first be
643                                 terminated via SIGTERM (unless the
644                                 signal to send is changed via
645                                 <varname>KillSignal=</varname>). If
646                                 then after a delay (configured via the
647                                 <varname>TimeoutSec=</varname> option)
648                                 processes still remain, the
649                                 termination request is repeated with
650                                 the SIGKILL signal (unless this is
651                                 disabled via the
652                                 <varname>SendSIGKILL=</varname>
653                                 option). See
654                                 <citerefentry><refentrytitle>kill</refentrytitle><manvolnum>2</manvolnum></citerefentry>
655                                 for more
656                                 information.</para></listitem>
657                         </varlistentry>
658
659                         <varlistentry>
660                                 <term><varname>KillSignal=</varname></term>
661                                 <listitem><para>Specifies which signal
662                                 to use when killing a
663                                 service. Defaults to SIGTERM.
664                                 </para></listitem>
665                         </varlistentry>
666
667                         <varlistentry>
668                                 <term><varname>SendSIGKILL=</varname></term>
669                                 <listitem><para>Specifies whether to
670                                 send SIGKILL to remaining processes
671                                 after a timeout, if the normal
672                                 shutdown procedure left processes of
673                                 the service around. Takes a boolean
674                                 value. Defaults to "yes".
675                                 </para></listitem>
676                         </varlistentry>
677
678                         <varlistentry>
679                                 <term><varname>NonBlocking=</varname></term>
680                                 <listitem><para>Set O_NONBLOCK flag
681                                 for all file descriptors passed via
682                                 socket-based activation. If true, all
683                                 file descriptors >= 3 (i.e. all except
684                                 STDIN/STDOUT/STDERR) will have
685                                 the O_NONBLOCK flag set and hence are in
686                                 non-blocking mode. This option is only
687                                 useful in conjunction with a socket
688                                 unit, as described in
689                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
690                                 to false.</para></listitem>
691                         </varlistentry>
692
693                         <varlistentry>
694                                 <term><varname>NotifyAccess=</varname></term>
695                                 <listitem><para>Controls access to the
696                                 service status notification socket, as
697                                 accessible via the
698                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
699                                 call. Takes one of
700                                 <option>none</option> (the default),
701                                 <option>main</option> or
702                                 <option>all</option>. If
703                                 <option>none</option> no daemon status
704                                 updates are accepted from the service
705                                 processes, all status update messages
706                                 are ignored. If <option>main</option>
707                                 only service updates sent from the
708                                 main process of the service are
709                                 accepted. If <option>all</option> all
710                                 services updates from all members of
711                                 the service's control group are
712                                 accepted. This option should be set to
713                                 open access to the notification socket
714                                 when using
715                                 <varname>Type=notify</varname> or
716                                 <varname>WatchdogUsec=</varname> (see
717                                 above). If those options are used but
718                                 <varname>NotifyAccess=</varname> not
719                                 configured it will be implicitly set
720                                 to
721                                 <option>main</option>.</para></listitem>
722                         </varlistentry>
723
724                         <varlistentry>
725                                 <term><varname>Sockets=</varname></term>
726                                 <listitem><para>Specifies the name of
727                                 the socket units this service shall
728                                 inherit the sockets from when the
729                                 service is started. Normally it
730                                 should not be necessary to use this
731                                 setting as all sockets whose unit
732                                 shares the same name as the service
733                                 (ignoring the different suffix of course)
734                                 are passed to the spawned
735                                 process.</para>
736
737                                 <para>Note that the same socket may be
738                                 passed to multiple processes at the
739                                 same time. Also note that a different
740                                 service may be activated on incoming
741                                 traffic than inherits the sockets. Or
742                                 in other words: The
743                                 <varname>Service=</varname> setting of
744                                 <filename>.socket</filename> units
745                                 doesn't have to match the inverse of the
746                                 <varname>Sockets=</varname> setting of
747                                 the <filename>.service</filename> it
748                                 refers to.</para></listitem>
749                         </varlistentry>
750
751                         <varlistentry>
752                                 <term><varname>FsckPassNo=</varname></term>
753                                 <listitem><para>Set the fsck passno
754                                 priority to use to order this service
755                                 in relation to other file system
756                                 checking services. This option is only
757                                 necessary to fix ordering in relation
758                                 to fsck jobs automatically created for
759                                 all <filename>/etc/fstab</filename>
760                                 entries with a value in the fs_passno
761                                 column > 0. As such it should only be
762                                 used as option for fsck
763                                 services. Almost always it is a better
764                                 choice to add explicit ordering
765                                 directives via
766                                 <varname>After=</varname> or
767                                 <varname>Before=</varname>,
768                                 instead. For more details see
769                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
770                                 used, pass an integer value in the
771                                 same range as
772                                 <filename>/etc/fstab</filename>'s
773                                 fs_passno column. See
774                                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
775                                 for details.</para></listitem>
776                         </varlistentry>
777
778                         <varlistentry>
779                                 <term><varname>StartLimitInterval=</varname></term>
780                                 <term><varname>StartLimitBurst=</varname></term>
781
782                                 <listitem><para>Configure service
783                                 start rate limiting. By default
784                                 services which are started more often
785                                 than 5 times within 10s are not
786                                 permitted to start any more times
787                                 until the 10s interval ends. With
788                                 these two options this rate limiting
789                                 may be modified. Use
790                                 <varname>StartLimitInterval=</varname>
791                                 to configure the checking interval
792                                 (defaults to 10s, set to 0 to disable
793                                 any kind of rate limiting). Use
794                                 <varname>StartLimitBurst=</varname> to
795                                 configure how many starts per interval
796                                 are allowed (defaults to 5). These
797                                 configuration options are particularly
798                                 useful in conjunction with
799                                 <varname>Restart=</varname>.</para></listitem>
800                         </varlistentry>
801
802                         <varlistentry>
803                                 <term><varname>StartLimitAction=</varname></term>
804
805                                 <listitem><para>Configure the action
806                                 to take if the rate limit configured
807                                 with
808                                 <varname>StartLimitInterval=</varname>
809                                 and
810                                 <varname>StartLimitBurst=</varname> is
811                                 hit. Takes one of
812                                 <option>none</option>,
813                                 <option>reboot</option>,
814                                 <option>reboot-force</option> or
815                                 <option>reboot-immediate</option>. If
816                                 <option>none</option> is set,
817                                 hitting the rate limit will trigger no
818                                 action besides that the start will not
819                                 be
820                                 permitted. <option>reboot</option>
821                                 causes a reboot following the normal
822                                 shutdown procedure (i.e. equivalent to
823                                 <command>systemctl reboot</command>),
824                                 <option>reboot-force</option> causes
825                                 an forced reboot which will terminate
826                                 all processes forcibly but should
827                                 cause no dirty file systems on reboot
828                                 (i.e. equivalent to <command>systemctl
829                                 reboot -f</command>) and
830                                 <option>reboot-immediate</option>
831                                 causes immediate execution of the
832                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
833                                 system call, which might result in
834                                 data loss.  Defaults to
835                                 <option>none</option>.</para></listitem>
836                         </varlistentry>
837
838                         <varlistentry>
839                                 <term><varname>FsckPassNo=</varname></term>
840
841                                 <listitem><para>If this is an file
842                                 system checking service specify the
843                                 pass number. This should not be used
844                                 for normal services.</para></listitem>
845                         </varlistentry>
846
847                 </variablelist>
848         </refsect1>
849
850         <refsect1>
851                   <title>See Also</title>
852                   <para>
853                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
854                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
855                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
856                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
857                   </para>
858         </refsect1>
859
860 </refentry>