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