man/systemd.service.xml

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   7   This file is part of systemd.
   8
   9   Copyright 2010 Lennart Poettering
  10
  11   systemd is free software; you can redistribute it and/or modify it
  12   under the terms of the GNU Lesser General Public License as published by
  13   the Free Software Foundation; either version 2.1 of the License, or
  14   (at your option) any later version.
  15
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  19   Lesser General Public License for more details.
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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>Service unit configuration</refpurpose>
  48         </refnamediv>
  49
  50         <refsynopsisdiv>
  51                 <para><filename><replaceable>service</replaceable>.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, and in
  76                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  77                 which define the way the processes of the service are
  78                 terminated, and in
  79                 <citerefentry><refentrytitle>systemd.cgroup</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  80                 which configure control group settings for the
  81                 processes of the service.</para>
  82
  83                 <para>Unless <varname>DefaultDependencies=</varname>
  84                 is set to <option>false</option>, service units will
  85                 implicitly have dependencies of type
  86                 <varname>Requires=</varname> and
  87                 <varname>After=</varname> on
  88                 <filename>basic.target</filename> as well as
  89                 dependencies of type <varname>Conflicts=</varname> and
  90                 <varname>Before=</varname> on
  91                 <filename>shutdown.target</filename>. These ensure
  92                 that normal service units pull in basic system
  93                 initialization, and are terminated cleanly prior to
  94                 system shutdown. Only services involved with early
  95                 boot or late system shutdown should disable this
  96                 option.</para>
  97
  98                 <para>If a service is requested under a certain name
  99                 but no unit configuration file is found, systemd looks
 100                 for a SysV init script by the same name (with the
 101                 <filename>.service</filename> suffix removed) and
 102                 dynamically creates a service unit from that
 103                 script. This is useful for compatibility with
 104                 SysV. Note that this compatibility is quite
 105                 comprehensive but not 100%. For details about the
 106                 incompatibilities see the <ulink
 107                 url="http://www.freedesktop.org/wiki/Software/systemd/Incompatibilities">Incompatibilities
 108                 with SysV</ulink> document.
 109                 </para>
 110         </refsect1>
 111
 112         <refsect1>
 113                 <title>Options</title>
 114
 115                 <para>Service files must include a
 116                 <literal>[Service]</literal> section, which carries
 117                 information about the service and the process it
 118                 supervises. A number of options that may be used in
 119                 this section are shared with other unit types. These
 120                 options are documented in
 121                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 122                 and
 123                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>. The
 124                 options specific to the <literal>[Service]</literal>
 125                 section of service units are the following:</para>
 126
 127                 <variablelist class='unit-directives'>
 128                         <varlistentry>
 129                                 <term><varname>Type=</varname></term>
 130
 131                                 <listitem><para>Configures the process
 132                                 start-up type for this service
 133                                 unit. One of <option>simple</option>,
 134                                 <option>forking</option>,
 135                                 <option>oneshot</option>,
 136                                 <option>dbus</option>,
 137                                 <option>notify</option> or
 138                                 <option>idle</option>.</para>
 139
 140                                 <para>If set to
 141                                 <option>simple</option> (the default
 142                                 value if <varname>BusName=</varname>
 143                                 is not specified) it is expected that
 144                                 the process configured with
 145                                 <varname>ExecStart=</varname> is the
 146                                 main process of the service. In this
 147                                 mode, if the process offers
 148                                 functionality to other processes on
 149                                 the system its communication channels
 150                                 should be installed before the daemon
 151                                 is started up (e.g. sockets set up by
 152                                 systemd, via socket activation), as
 153                                 systemd will immediately proceed
 154                                 starting follow-up units.</para>
 155
 156                                 <para>If set to
 157                                 <option>forking</option> it is
 158                                 expected that the process configured
 159                                 with <varname>ExecStart=</varname>
 160                                 will call <function>fork()</function>
 161                                 as part of its start-up. The parent process is
 162                                 expected to exit when start-up is
 163                                 complete and all communication
 164                                 channels set up. The child continues
 165                                 to run as the main daemon
 166                                 process. This is the behavior of
 167                                 traditional UNIX daemons. If this
 168                                 setting is used, it is recommended to
 169                                 also use the
 170                                 <varname>PIDFile=</varname> option, so
 171                                 that systemd can identify the main
 172                                 process of the daemon. systemd will
 173                                 proceed starting follow-up units as
 174                                 soon as the parent process
 175                                 exits.</para>
 176
 177                                 <para>Behavior of
 178                                 <option>oneshot</option> is similar
 179                                 to <option>simple</option>, however
 180                                 it is expected that the process has to
 181                                 exit before systemd starts follow-up
 182                                 units. <varname>RemainAfterExit=</varname>
 183                                 is particularly useful for this type
 184                                 of service.</para>
 185
 186                                 <para>Behavior of
 187                                 <option>dbus</option> is similar to
 188                                 <option>simple</option>, however it is
 189                                 expected that the daemon acquires a
 190                                 name on the D-Bus bus, as configured
 191                                 by
 192                                 <varname>BusName=</varname>. systemd
 193                                 will proceed starting follow-up units
 194                                 after the D-Bus bus name has been
 195                                 acquired. Service units with this
 196                                 option configured implicitly gain
 197                                 dependencies on the
 198                                 <filename>dbus.socket</filename>
 199                                 unit. This type is the default if
 200                                 <varname>BusName=</varname> is
 201                                 specified.</para>
 202
 203                                 <para>Behavior of
 204                                 <option>notify</option> is similar to
 205                                 <option>simple</option>, however it is
 206                                 expected that the daemon sends a
 207                                 notification message via
 208                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 209                                 or an equivalent call when it finished
 210                                 starting up. systemd will proceed
 211                                 starting follow-up units after this
 212                                 notification message has been sent. If
 213                                 this option is used
 214                                 <varname>NotifyAccess=</varname> (see
 215                                 below) should be set to open access to
 216                                 the notification socket provided by
 217                                 systemd. If
 218                                 <varname>NotifyAccess=</varname> is
 219                                 not set, it will be implicitly set to
 220                                 <option>main</option>. Note that
 221                                 currently
 222                                 <varname>Type=</varname><option>notify</option>
 223                                 won't work if used in combination with
 224                                 <varname>PrivateNetwork=</varname><option>yes</option>.</para>
 225
 226                                 <para>Behavior of
 227                                 <option>idle</option> is very similar
 228                                 to <option>simple</option>, however
 229                                 actual execution of the service
 230                                 binary is delayed until all jobs are
 231                                 dispatched. This may be used to avoid
 232                                 interleaving of output of shell
 233                                 services with the status output on the
 234                                 console.</para>
 235                                 </listitem>
 236                         </varlistentry>
 237
 238                         <varlistentry>
 239                                 <term><varname>RemainAfterExit=</varname></term>
 240
 241                                 <listitem><para>Takes a boolean value
 242                                 that specifies whether the service
 243                                 shall be considered active even when
 244                                 all its processes exited. Defaults to
 245                                 <option>no</option>.</para>
 246                                 </listitem>
 247                         </varlistentry>
 248
 249                         <varlistentry>
 250                                 <term><varname>GuessMainPID=</varname></term>
 251
 252                                 <listitem><para>Takes a boolean value
 253                                 that specifies whether systemd should
 254                                 try to guess the main PID of a service
 255                                 if it cannot be determined
 256                                 reliably. This option is ignored
 257                                 unless <option>Type=forking</option>
 258                                 is set and <option>PIDFile=</option>
 259                                 is unset because for the other types
 260                                 or with an explicitly configured PID
 261                                 file the main PID is always known. The
 262                                 guessing algorithm might come to
 263                                 incorrect conclusions if a daemon
 264                                 consists of more than one process. If
 265                                 the main PID cannot be determined
 266                                 failure detection and automatic
 267                                 restarting of a service will not work
 268                                 reliably. Defaults to
 269                                 <option>yes</option>.</para>
 270                                 </listitem>
 271                         </varlistentry>
 272
 273                         <varlistentry>
 274                                 <term><varname>PIDFile=</varname></term>
 275
 276                                 <listitem><para>Takes an absolute file
 277                                 name pointing to the PID file of this
 278                                 daemon. Use of this option is
 279                                 recommended for services where
 280                                 <varname>Type=</varname> is set to
 281                                 <option>forking</option>. systemd will
 282                                 read the PID of the main process of
 283                                 the daemon after start-up of the
 284                                 service. systemd will not write to the
 285                                 file configured here.</para>
 286                                 </listitem>
 287                         </varlistentry>
 288
 289                         <varlistentry>
 290                                 <term><varname>BusName=</varname></term>
 291
 292                                 <listitem><para>Takes a D-Bus bus
 293                                 name, that this service is reachable
 294                                 as. This option is mandatory for
 295                                 services where
 296                                 <varname>Type=</varname> is set to
 297                                 <option>dbus</option>, but its use
 298                                 is otherwise recommended as well if
 299                                 the process takes a name on the D-Bus
 300                                 bus.</para>
 301                                 </listitem>
 302                         </varlistentry>
 303
 304                         <varlistentry>
 305                                 <term><varname>ExecStart=</varname></term>
 306                                 <listitem><para>Commands with their
 307                                 arguments that are executed when this
 308                                 service is started. The first
 309                                 argument must be an absolute path
 310                                 name.</para>
 311
 312                                 <para>When <varname>Type</varname> is
 313                                 not <option>oneshot</option>, only one
 314                                 command may be given. When
 315                                 <varname>Type=oneshot</varname> is
 316                                 used, more than one command may be
 317                                 specified. Multiple command lines may
 318                                 be concatenated in a single directive,
 319                                 by separating them with semicolons
 320                                 (these semicolons must be passed as
 321                                 separate words). Alternatively, this
 322                                 directive may be specified more than
 323                                 once with the same effect. However,
 324                                 the latter syntax is not recommended
 325                                 for compatibility with parsers
 326                                 suitable for XDG
 327                                 <filename>.desktop</filename> files.
 328                                 Lone semicolons may be escaped as
 329                                 <literal>\;</literal>. If the empty
 330                                 string is assigned to this option the
 331                                 list of commands to start is reset,
 332                                 prior assignments of this option will
 333                                 have no effect.</para>
 334
 335                                 <para>If more than one command is
 336                                 specified, the commands are invoked
 337                                 one by one sequentially in the order
 338                                 they appear in the unit file. If one
 339                                 of the commands fails (and is not
 340                                 prefixed with <literal>-</literal>),
 341                                 other lines are not executed and the
 342                                 unit is considered failed.</para>
 343
 344                                 <para>Unless
 345                                 <varname>Type=forking</varname> is
 346                                 set, the process started via this
 347                                 command line will be considered the
 348                                 main process of the daemon.</para>
 349
 350                                 <para>The command line accepts
 351                                 <literal>%</literal> specifiers as
 352                                 described in
 353                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Note
 354                                 that the first argument of the command
 355                                 line (i.e. the program to execute) may
 356                                 not include specifiers.</para>
 357
 358                                 <para>Basic environment variable
 359                                 substitution is supported. Use
 360                                 <literal>${FOO}</literal> as part of a
 361                                 word, or as a word of its own on the
 362                                 command line, in which case it will be
 363                                 replaced by the value of the
 364                                 environment variable including all
 365                                 whitespace it contains, resulting in a
 366                                 single argument.  Use
 367                                 <literal>$FOO</literal> as a separate
 368                                 word on the command line, in which
 369                                 case it will be replaced by the value
 370                                 of the environment variable split up
 371                                 at whitespace, resulting in zero or
 372                                 more arguments. Note that the first
 373                                 argument (i.e. the program to execute)
 374                                 may not be a variable, since it must
 375                                 be a literal and absolute path
 376                                 name.</para>
 377
 378                                 <para>Optionally, if the absolute file
 379                                 name is prefixed with
 380                                 <literal>@</literal>, the second token
 381                                 will be passed as
 382                                 <literal>argv[0]</literal> to the
 383                                 executed process, followed by the
 384                                 further arguments specified. If the
 385                                 absolute filename is prefixed with
 386                                 <literal>-</literal> an exit code of
 387                                 the command normally considered a
 388                                 failure (i.e. non-zero exit status or
 389                                 abnormal exit due to signal) is ignored
 390                                 and considered success. If both
 391                                 <literal>-</literal> and
 392                                 <literal>@</literal> are used they
 393                                 can appear in either order.</para>
 394
 395                                 <para>Note that this setting does not
 396                                 directly support shell command
 397                                 lines. If shell command lines are to
 398                                 be used they need to be passed
 399                                 explicitly to a shell implementation
 400                                 of some kind. Example:</para>
 401                                 <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'
 402                                 </programlisting>
 403
 404                                 <para>For services run by a user
 405                                 instance of systemd the special
 406                                 environment variable
 407                                 <varname>$MANAGERPID</varname> is set
 408                                 to the PID of the systemd
 409                                 instance.</para>
 410                                 </listitem>
 411                         </varlistentry>
 412
 413                         <varlistentry>
 414                                 <term><varname>ExecStartPre=</varname></term>
 415                                 <term><varname>ExecStartPost=</varname></term>
 416                                 <listitem><para>Additional commands
 417                                 that are executed before or after
 418                                 the command in
 419                                 <varname>ExecStart=</varname>, respectively.
 420                                 Syntax is the same as for
 421                                 <varname>ExecStart=</varname>, except
 422                                 that multiple command lines are allowed
 423                                 and the commands are executed one
 424                                 after the other, serially.</para>
 425
 426                                 <para>If any of those commands (not
 427                                 prefixed with <literal>-</literal>)
 428                                 fail, the rest are not executed and
 429                                 the unit is considered failed.</para>
 430                                 </listitem>
 431                         </varlistentry>
 432
 433                         <varlistentry>
 434                                 <term><varname>ExecReload=</varname></term>
 435                                 <listitem><para>Commands to execute to
 436                                 trigger a configuration reload in the
 437                                 service. This argument takes multiple
 438                                 command lines, following the same
 439                                 scheme as described for
 440                                 <varname>ExecStart=</varname>
 441                                 above. Use of this setting is
 442                                 optional. Specifier and environment
 443                                 variable substitution is supported
 444                                 here following the same scheme as for
 445                                 <varname>ExecStart=</varname>.</para>
 446
 447                                 <para>One additional special
 448                                 environment variables is set: if known
 449                                 <varname>$MAINPID</varname> is set to
 450                                 the main process of the daemon, and
 451                                 may be used for command lines like the
 452                                 following:</para>
 453
 454                                 <programlisting>/bin/kill -HUP $MAINPID</programlisting>
 455                                 </listitem>
 456                         </varlistentry>
 457
 458                         <varlistentry>
 459                                 <term><varname>ExecStop=</varname></term>
 460                                 <listitem><para>Commands to execute to
 461                                 stop the service started via
 462                                 <varname>ExecStart=</varname>. This
 463                                 argument takes multiple command lines,
 464                                 following the same scheme as described
 465                                 for <varname>ExecStart=</varname>
 466                                 above. Use of this setting is
 467                                 optional. All processes remaining for
 468                                 a service after the commands
 469                                 configured in this option are run are
 470                                 terminated according to the
 471                                 <varname>KillMode=</varname> setting
 472                                 (see
 473                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
 474                                 this option is not specified the
 475                                 process is terminated right-away when
 476                                 service stop is requested. Specifier
 477                                 and environment variable substitution
 478                                 is supported (including
 479                                 <varname>$MAINPID</varname>, see
 480                                 above).</para></listitem>
 481                         </varlistentry>
 482
 483                         <varlistentry>
 484                                 <term><varname>ExecStopPost=</varname></term>
 485                                 <listitem><para>Additional commands
 486                                 that are executed after the service
 487                                 was stopped. This includes cases where
 488                                 the commands configured in
 489                                 <varname>ExecStop=</varname> were used,
 490                                 where the service does not have any
 491                                 <varname>ExecStop=</varname> defined, or
 492                                 where the service exited unexpectedly. This
 493                                 argument takes multiple command lines,
 494                                 following the same scheme as described
 495                                 for <varname>ExecStart</varname>. Use
 496                                 of these settings is
 497                                 optional. Specifier and environment
 498                                 variable substitution is
 499                                 supported.</para></listitem>
 500                         </varlistentry>
 501
 502                         <varlistentry>
 503                                 <term><varname>RestartSec=</varname></term>
 504                                 <listitem><para>Configures the time to
 505                                 sleep before restarting a service (as
 506                                 configured with
 507                                 <varname>Restart=</varname>). Takes a
 508                                 unit-less value in seconds, or a time
 509                                 span value such as "5min
 510                                 20s". Defaults to
 511                                 100ms.</para></listitem>
 512                         </varlistentry>
 513
 514                         <varlistentry>
 515                                 <term><varname>TimeoutStartSec=</varname></term>
 516                                 <listitem><para>Configures the time to
 517                                 wait for start-up. If a
 518                                 daemon service does not signal
 519                                 start-up completion within the
 520                                 configured time, the service will be
 521                                 considered failed and be shut down
 522                                 again.
 523                                 Takes a unit-less value in seconds, or a
 524                                 time span value such as "5min
 525                                 20s". Pass 0 to disable the timeout
 526                                 logic. Defaults to 90s, except when
 527                                 <varname>Type=oneshot</varname> is
 528                                 used in which case the timeout
 529                                 is disabled by default.
 530                                 </para></listitem>
 531                         </varlistentry>
 532
 533                         <varlistentry>
 534                                 <term><varname>TimeoutStopSec=</varname></term>
 535                                 <listitem><para>Configures the time to
 536                                 wait for stop. If a service is asked
 537                                 to stop but does not terminate in the
 538                                 specified time, it will be terminated
 539                                 forcibly via <constant>SIGTERM</constant>, and after
 540                                 another delay of this time with
 541                                 <constant>SIGKILL</constant> (See
 542                                 <varname>KillMode=</varname>
 543                                 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 544                                 Takes a unit-less value in seconds, or a
 545                                 time span value such as "5min
 546                                 20s". Pass 0 to disable the timeout
 547                                 logic. Defaults to 90s.
 548                                 </para></listitem>
 549                         </varlistentry>
 550
 551                         <varlistentry>
 552                                 <term><varname>TimeoutSec=</varname></term>
 553                                 <listitem><para>A shorthand for configuring
 554                                 both <varname>TimeoutStartSec=</varname>
 555                                 and <varname>TimeoutStopSec=</varname>
 556                                 to the specified value.
 557                                 </para></listitem>
 558                         </varlistentry>
 559
 560                         <varlistentry>
 561                                 <term><varname>WatchdogSec=</varname></term>
 562                                 <listitem><para>Configures the
 563                                 watchdog timeout for a service. The
 564                                 watchdog is activated when the start-up is
 565                                 completed. The service must call
 566                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 567                                 regularly with "WATCHDOG=1" (i.e. the
 568                                 "keep-alive ping"). If the time
 569                                 between two such calls is larger than
 570                                 the configured time then the service
 571                                 is placed in a failure state. By
 572                                 setting <varname>Restart=</varname> to
 573                                 <option>on-failure</option> or
 574                                 <option>always</option> the service
 575                                 will be automatically restarted. The
 576                                 time configured here will be passed to
 577                                 the executed service process in the
 578                                 <varname>WATCHDOG_USEC=</varname>
 579                                 environment variable. This allows
 580                                 daemons to automatically enable the
 581                                 keep-alive pinging logic if watchdog
 582                                 support is enabled for the service. If
 583                                 this option is used
 584                                 <varname>NotifyAccess=</varname> (see
 585                                 below) should be set to open access to
 586                                 the notification socket provided by
 587                                 systemd. If
 588                                 <varname>NotifyAccess=</varname> is
 589                                 not set, it will be implicitly set to
 590                                 <option>main</option>. Defaults to 0,
 591                                 which disables this
 592                                 feature.</para></listitem>
 593                         </varlistentry>
 594
 595                         <varlistentry>
 596                                 <term><varname>Restart=</varname></term>
 597                                 <listitem><para>Configures whether the
 598                                 service shall be restarted when the
 599                                 service process exits, is killed,
 600                                 or a timeout is reached. The service
 601                                 process may be the main service
 602                                 process, but also one of the processes
 603                                 specified with
 604                                 <varname>ExecStartPre=</varname>,
 605                                 <varname>ExecStartPost=</varname>,
 606                                 <varname>ExecStopPre=</varname>,
 607                                 <varname>ExecStopPost=</varname>, or
 608                                 <varname>ExecReload=</varname>.
 609                                 When the death of the process is a
 610                                 result of systemd operation (e.g. service
 611                                 stop or restart), the service will not be
 612                                 restarted. Timeouts include missing
 613                                 the watchdog "keep-alive ping"
 614                                 deadline and a service start, reload,
 615                                 and stop operation timeouts.</para>
 616
 617                                 <para>Takes one of
 618                                 <option>no</option>,
 619                                 <option>on-success</option>,
 620                                 <option>on-failure</option>,
 621                                 <option>on-abort</option>, or
 622                                 <option>always</option>. If set to
 623                                 <option>no</option> (the default) the
 624                                 service will not be restarted. If set to
 625                                 <option>on-success</option> it will be
 626                                 restarted only when the service process
 627                                 exits cleanly.
 628                                 In this context, a clean exit means
 629                                 an exit code of 0, or one of the signals
 630                                 <constant>SIGHUP</constant>, <constant>SIGINT</constant>, <constant>SIGTERM</constant>, or <constant>SIGPIPE</constant>, and
 631                                 additionally, exit statuses and signals
 632                                 specified in <varname>SuccessExitStatus=</varname>.
 633                                 If set to <option>on-failure</option>
 634                                 the service will be restarted when the
 635                                 process exits with an nonzero exit code,
 636                                 is terminated by a signal (including on
 637                                 core dump), when an operation (such as
 638                                 service reload) times out, and when the
 639                                 configured watchdog timeout is triggered.
 640                                 If set to
 641                                 <option>on-abort</option> the service
 642                                 will be restarted only if the service
 643                                 process exits due to an uncaught
 644                                 signal not specified as a clean exit
 645                                 status.
 646                                 If set to
 647                                 <option>always</option> the service
 648                                 will be restarted regardless whether
 649                                 it exited cleanly or not, got
 650                                 terminated abnormally by a signal or
 651                                 hit a timeout.</para>
 652
 653                                 <para>In addition to the above settings,
 654                                 the service will not be restarted if the
 655                                 exit code or signal is specified in
 656                                 <varname>RestartPreventExitStatus=</varname>
 657                                 (see below).</para></listitem>
 658                         </varlistentry>
 659
 660                         <varlistentry>
 661                                 <term><varname>SuccessExitStatus=</varname></term>
 662                                 <listitem><para>Takes a list of exit
 663                                 status definitions that when returned
 664                                 by the main service process will be
 665                                 considered successful termination, in
 666                                 addition to the normal successful exit
 667                                 code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
 668                                 <constant>SIGTERM</constant> and <constant>SIGPIPE</constant>. Exit status
 669                                 definitions can either be numeric exit
 670                                 codes or termination signal names,
 671                                 separated by spaces. Example:
 672                                 <literal>SuccessExitStatus=1 2 8
 673                                 <constant>SIGKILL</constant></literal>, ensures that exit
 674                                 codes 1, 2, 8 and the termination
 675                                 signal <constant>SIGKILL</constant> are considered clean
 676                                 service terminations. This option may
 677                                 appear more than once in which case
 678                                 the list of successful exit statuses
 679                                 is merged. If the empty string is
 680                                 assigned to this option the list is
 681                                 reset, all prior assignments of this
 682                                 option will have no
 683                                 effect.</para></listitem>
 684                         </varlistentry>
 685
 686                         <varlistentry>
 687                                 <term><varname>RestartPreventExitStatus=</varname></term>
 688                                 <listitem><para>Takes a list of exit
 689                                 status definitions that when returned
 690                                 by the main service process will
 691                                 prevent automatic service restarts
 692                                 regardless of the restart setting
 693                                 configured with
 694                                 <varname>Restart=</varname>. Exit
 695                                 status definitions can either be
 696                                 numeric exit codes or termination
 697                                 signal names, and are separated by
 698                                 spaces. Defaults to the empty list, so
 699                                 that by default no exit status is
 700                                 excluded from the configured restart
 701                                 logic. Example:
 702                                 <literal>RestartPreventExitStatus=1 6
 703                                 SIGABRT</literal>, ensures that exit
 704                                 codes 1 and 6 and the termination
 705                                 signal SIGABRT will not result in
 706                                 automatic service restarting. This
 707                                 option may appear more than once in
 708                                 which case the list of restart preventing
 709                                 statuses is merged. If the empty
 710                                 string is assigned to this option the
 711                                 list is reset, all prior assignments
 712                                 of this option will have no
 713                                 effect.</para></listitem>
 714                         </varlistentry>
 715
 716                         <varlistentry>
 717                                 <term><varname>PermissionsStartOnly=</varname></term>
 718                                 <listitem><para>Takes a boolean
 719                                 argument. If true, the permission
 720                                 related execution options as
 721                                 configured with
 722                                 <varname>User=</varname> and similar
 723                                 options (see
 724                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 725                                 for more information) are only applied
 726                                 to the process started with
 727                                 <varname>ExecStart=</varname>, and not
 728                                 to the various other
 729                                 <varname>ExecStartPre=</varname>,
 730                                 <varname>ExecStartPost=</varname>,
 731                                 <varname>ExecReload=</varname>,
 732                                 <varname>ExecStop=</varname>,
 733                                 <varname>ExecStopPost=</varname>
 734                                 commands. If false, the setting is
 735                                 applied to all configured commands the
 736                                 same way. Defaults to
 737                                 false.</para></listitem>
 738                         </varlistentry>
 739
 740                         <varlistentry>
 741                                 <term><varname>RootDirectoryStartOnly=</varname></term>
 742                                 <listitem><para>Takes a boolean
 743                                 argument. If true, the root directory
 744                                 as configured with the
 745                                 <varname>RootDirectory=</varname>
 746                                 option (see
 747                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 748                                 for more information) is only applied
 749                                 to the process started with
 750                                 <varname>ExecStart=</varname>, and not
 751                                 to the various other
 752                                 <varname>ExecStartPre=</varname>,
 753                                 <varname>ExecStartPost=</varname>,
 754                                 <varname>ExecReload=</varname>,
 755                                 <varname>ExecStop=</varname>,
 756                                 <varname>ExecStopPost=</varname>
 757                                 commands. If false, the setting is
 758                                 applied to all configured commands the
 759                                 same way. Defaults to
 760                                 false.</para></listitem>
 761                         </varlistentry>
 762
 763                         <varlistentry>
 764                                 <term><varname>NonBlocking=</varname></term>
 765                                 <listitem><para>Set O_NONBLOCK flag
 766                                 for all file descriptors passed via
 767                                 socket-based activation. If true, all
 768                                 file descriptors >= 3 (i.e. all except
 769                                 STDIN/STDOUT/STDERR) will have
 770                                 the O_NONBLOCK flag set and hence are in
 771                                 non-blocking mode. This option is only
 772                                 useful in conjunction with a socket
 773                                 unit, as described in
 774                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
 775                                 to false.</para></listitem>
 776                         </varlistentry>
 777
 778                         <varlistentry>
 779                                 <term><varname>NotifyAccess=</varname></term>
 780                                 <listitem><para>Controls access to the
 781                                 service status notification socket, as
 782                                 accessible via the
 783                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 784                                 call. Takes one of
 785                                 <option>none</option> (the default),
 786                                 <option>main</option> or
 787                                 <option>all</option>. If
 788                                 <option>none</option> no daemon status
 789                                 updates are accepted from the service
 790                                 processes, all status update messages
 791                                 are ignored. If <option>main</option>
 792                                 only service updates sent from the
 793                                 main process of the service are
 794                                 accepted. If <option>all</option> all
 795                                 services updates from all members of
 796                                 the service's control group are
 797                                 accepted. This option should be set to
 798                                 open access to the notification socket
 799                                 when using
 800                                 <varname>Type=notify</varname> or
 801                                 <varname>WatchdogSec=</varname> (see
 802                                 above). If those options are used but
 803                                 <varname>NotifyAccess=</varname> not
 804                                 configured it will be implicitly set
 805                                 to
 806                                 <option>main</option>.</para></listitem>
 807                         </varlistentry>
 808
 809                         <varlistentry>
 810                                 <term><varname>Sockets=</varname></term>
 811                                 <listitem><para>Specifies the name of
 812                                 the socket units this service shall
 813                                 inherit the sockets from when the
 814                                 service is started. Normally it
 815                                 should not be necessary to use this
 816                                 setting as all sockets whose unit
 817                                 shares the same name as the service
 818                                 (ignoring the different suffix of course)
 819                                 are passed to the spawned
 820                                 process.</para>
 821
 822                                 <para>Note that the same socket may be
 823                                 passed to multiple processes at the
 824                                 same time. Also note that a different
 825                                 service may be activated on incoming
 826                                 traffic than inherits the sockets. Or
 827                                 in other words: the
 828                                 <varname>Service=</varname> setting of
 829                                 <filename>.socket</filename> units
 830                                 does not have to match the inverse of
 831                                 the <varname>Sockets=</varname>
 832                                 setting of the
 833                                 <filename>.service</filename> it
 834                                 refers to.</para>
 835
 836                                 <para>This option may appear more than
 837                                 once, in which case the list of socket
 838                                 units is merged. If the empty string
 839                                 is assigned to this option the list of
 840                                 sockets is reset, all prior uses of
 841                                 this setting will have no
 842                                 effect.</para></listitem>
 843                         </varlistentry>
 844
 845                         <varlistentry>
 846                                 <term><varname>StartLimitInterval=</varname></term>
 847                                 <term><varname>StartLimitBurst=</varname></term>
 848
 849                                 <listitem><para>Configure service
 850                                 start rate limiting. By default
 851                                 services which are started more often
 852                                 than 5 times within 10s are not
 853                                 permitted to start any more times
 854                                 until the 10s interval ends. With
 855                                 these two options this rate limiting
 856                                 may be modified. Use
 857                                 <varname>StartLimitInterval=</varname>
 858                                 to configure the checking interval
 859                                 (defaults to 10s, set to 0 to disable
 860                                 any kind of rate limiting). Use
 861                                 <varname>StartLimitBurst=</varname> to
 862                                 configure how many starts per interval
 863                                 are allowed (defaults to 5). These
 864                                 configuration options are particularly
 865                                 useful in conjunction with
 866                                 <varname>Restart=</varname>, however
 867                                 apply to all kinds of starts
 868                                 (including manual), not just those
 869                                 triggered by the
 870                                 <varname>Restart=</varname> logic.
 871                                 Note that units which are configured
 872                                 for <varname>Restart=</varname> and
 873                                 which reach the start limit are not
 874                                 attempted to be restarted anymore,
 875                                 however they may still be restarted
 876                                 manually at a later point from which
 877                                 point on the restart logic is again
 878                                 activated. Note that
 879                                 <command>systemctl
 880                                 reset-failed</command> will cause the
 881                                 restart rate counter for a service to
 882                                 be flushed, which is useful if the
 883                                 administrator wants to manually start
 884                                 a service and the start limit
 885                                 interferes with
 886                                 that.</para></listitem>
 887                         </varlistentry>
 888
 889                         <varlistentry>
 890                                 <term><varname>StartLimitAction=</varname></term>
 891
 892                                 <listitem><para>Configure the action
 893                                 to take if the rate limit configured
 894                                 with
 895                                 <varname>StartLimitInterval=</varname>
 896                                 and
 897                                 <varname>StartLimitBurst=</varname> is
 898                                 hit. Takes one of
 899                                 <option>none</option>,
 900                                 <option>reboot</option>,
 901                                 <option>reboot-force</option> or
 902                                 <option>reboot-immediate</option>. If
 903                                 <option>none</option> is set,
 904                                 hitting the rate limit will trigger no
 905                                 action besides that the start will not
 906                                 be
 907                                 permitted. <option>reboot</option>
 908                                 causes a reboot following the normal
 909                                 shutdown procedure (i.e. equivalent to
 910                                 <command>systemctl reboot</command>),
 911                                 <option>reboot-force</option> causes
 912                                 an forced reboot which will terminate
 913                                 all processes forcibly but should
 914                                 cause no dirty file systems on reboot
 915                                 (i.e. equivalent to <command>systemctl
 916                                 reboot -f</command>) and
 917                                 <option>reboot-immediate</option>
 918                                 causes immediate execution of the
 919                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 920                                 system call, which might result in
 921                                 data loss.  Defaults to
 922                                 <option>none</option>.</para></listitem>
 923                         </varlistentry>
 924
 925                 </variablelist>
 926
 927                 <para>Check
 928                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 929                 and
 930                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 931                 for more settings.</para>
 932
 933         </refsect1>
 934
 935         <refsect1>
 936                 <title>Compatibility Options</title>
 937
 938                 <para>The following options are also available in the
 939                 <literal>[Service]</literal> section, but exist purely
 940                 for compatibility reasons and should not be used in
 941                 newly written service files.</para>
 942
 943                 <variablelist class='unit-directives'>
 944                         <varlistentry>
 945                                 <term><varname>SysVStartPriority=</varname></term>
 946                                 <listitem><para>Set the SysV start
 947                                 priority to use to order this service
 948                                 in relation to SysV services lacking
 949                                 LSB headers. This option is only
 950                                 necessary to fix ordering in relation
 951                                 to legacy SysV services, that have no
 952                                 ordering information encoded in the
 953                                 script headers. As such it should only
 954                                 be used as temporary compatibility
 955                                 option, and not be used in new unit
 956                                 files. Almost always it is a better
 957                                 choice to add explicit ordering
 958                                 directives via
 959                                 <varname>After=</varname> or
 960                                 <varname>Before=</varname>,
 961                                 instead. For more details see
 962                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
 963                                 used, pass an integer value in the
 964                                 range 0-99.</para></listitem>
 965                         </varlistentry>
 966
 967                         <varlistentry>
 968                                 <term><varname>FsckPassNo=</varname></term>
 969                                 <listitem><para>Set the fsck passno
 970                                 priority to use to order this service
 971                                 in relation to other file system
 972                                 checking services. This option is only
 973                                 necessary to fix ordering in relation
 974                                 to fsck jobs automatically created for
 975                                 all <filename>/etc/fstab</filename>
 976                                 entries with a value in the fs_passno
 977                                 column > 0. As such it should only be
 978                                 used as option for fsck
 979                                 services. Almost always it is a better
 980                                 choice to add explicit ordering
 981                                 directives via
 982                                 <varname>After=</varname> or
 983                                 <varname>Before=</varname>,
 984                                 instead. For more details see
 985                                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. If
 986                                 used, pass an integer value in the
 987                                 same range as
 988                                 <filename>/etc/fstab</filename>'s
 989                                 fs_passno column. See
 990                                 <citerefentry><refentrytitle>fstab</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 991                                 for details.</para></listitem>
 992                         </varlistentry>
 993
 994                 </variablelist>
 995         </refsect1>
 996
 997         <refsect1>
 998                   <title>See Also</title>
 999                   <para>
1000                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1001                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
1002                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1003                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1004                           <citerefentry><refentrytitle>systemd.cgroup</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1005                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1006                           <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1007                   </para>
1008         </refsect1>
1009
1010 </refentry>