man/systemd.service.xml

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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.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
  80                 which configure resource control 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                                 if neither
 143                                 <varname>Type=</varname> nor
 144                                 <varname>BusName=</varname>, but
 145                                 <varname>ExecStart=</varname> are
 146                                 specified), it is expected that the
 147                                 process configured with
 148                                 <varname>ExecStart=</varname> is the
 149                                 main process of the service. In this
 150                                 mode, if the process offers
 151                                 functionality to other processes on
 152                                 the system, its communication channels
 153                                 should be installed before the daemon
 154                                 is started up (e.g. sockets set up by
 155                                 systemd, via socket activation), as
 156                                 systemd will immediately proceed
 157                                 starting follow-up units.</para>
 158
 159                                 <para>If set to
 160                                 <option>forking</option>, it is
 161                                 expected that the process configured
 162                                 with <varname>ExecStart=</varname>
 163                                 will call <function>fork()</function>
 164                                 as part of its start-up. The parent process is
 165                                 expected to exit when start-up is
 166                                 complete and all communication
 167                                 channels are set up. The child continues
 168                                 to run as the main daemon
 169                                 process. This is the behavior of
 170                                 traditional UNIX daemons. If this
 171                                 setting is used, it is recommended to
 172                                 also use the
 173                                 <varname>PIDFile=</varname> option, so
 174                                 that systemd can identify the main
 175                                 process of the daemon. systemd will
 176                                 proceed with starting follow-up units
 177                                 as soon as the parent process
 178                                 exits.</para>
 179
 180                                 <para>Behavior of
 181                                 <option>oneshot</option> is similar to
 182                                 <option>simple</option>; however, it
 183                                 is expected that the process has to
 184                                 exit before systemd starts follow-up
 185                                 units. <varname>RemainAfterExit=</varname>
 186                                 is particularly useful for this type
 187                                 of service. This is the implied
 188                                 default if neither
 189                                 <varname>Type=</varname> or
 190                                 <varname>ExecStart=</varname> are
 191                                 specified.</para>
 192
 193                                 <para>Behavior of
 194                                 <option>dbus</option> is similar to
 195                                 <option>simple</option>; however, it is
 196                                 expected that the daemon acquires a
 197                                 name on the D-Bus bus, as configured
 198                                 by
 199                                 <varname>BusName=</varname>. systemd
 200                                 will proceed with starting follow-up
 201                                 units after the D-Bus bus name has been
 202                                 acquired. Service units with this
 203                                 option configured implicitly gain
 204                                 dependencies on the
 205                                 <filename>dbus.socket</filename>
 206                                 unit. This type is the default if
 207                                 <varname>BusName=</varname> is
 208                                 specified.</para>
 209
 210                                 <para>Behavior of
 211                                 <option>notify</option> is similar to
 212                                 <option>simple</option>; however, it is
 213                                 expected that the daemon sends a
 214                                 notification message via
 215                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 216                                 or an equivalent call when it has finished
 217                                 starting up. systemd will proceed with
 218                                 starting follow-up units after this
 219                                 notification message has been sent. If
 220                                 this option is used,
 221                                 <varname>NotifyAccess=</varname> (see
 222                                 below) should be set to open access to
 223                                 the notification socket provided by
 224                                 systemd. If
 225                                 <varname>NotifyAccess=</varname> is
 226                                 not set, it will be implicitly set to
 227                                 <option>main</option>. Note that
 228                                 currently
 229                                 <varname>Type=</varname><option>notify</option>
 230                                 will not work if used in combination with
 231                                 <varname>PrivateNetwork=</varname><option>yes</option>.</para>
 232
 233                                 <para>Behavior of
 234                                 <option>idle</option> is very similar
 235                                 to <option>simple</option>; however,
 236                                 actual execution of the service
 237                                 binary is delayed until all jobs are
 238                                 dispatched. This may be used to avoid
 239                                 interleaving of output of shell
 240                                 services with the status output on the
 241                                 console.</para>
 242                                 </listitem>
 243                         </varlistentry>
 244
 245                         <varlistentry>
 246                                 <term><varname>RemainAfterExit=</varname></term>
 247
 248                                 <listitem><para>Takes a boolean value
 249                                 that specifies whether the service
 250                                 shall be considered active even when
 251                                 all its processes exited. Defaults to
 252                                 <option>no</option>.</para>
 253                                 </listitem>
 254                         </varlistentry>
 255
 256                         <varlistentry>
 257                                 <term><varname>GuessMainPID=</varname></term>
 258
 259                                 <listitem><para>Takes a boolean value
 260                                 that specifies whether systemd should
 261                                 try to guess the main PID of a service
 262                                 if it cannot be determined
 263                                 reliably. This option is ignored
 264                                 unless <option>Type=forking</option>
 265                                 is set and <option>PIDFile=</option>
 266                                 is unset because for the other types
 267                                 or with an explicitly configured PID
 268                                 file, the main PID is always known. The
 269                                 guessing algorithm might come to
 270                                 incorrect conclusions if a daemon
 271                                 consists of more than one process. If
 272                                 the main PID cannot be determined,
 273                                 failure detection and automatic
 274                                 restarting of a service will not work
 275                                 reliably. Defaults to
 276                                 <option>yes</option>.</para>
 277                                 </listitem>
 278                         </varlistentry>
 279
 280                         <varlistentry>
 281                                 <term><varname>PIDFile=</varname></term>
 282
 283                                 <listitem><para>Takes an absolute file
 284                                 name pointing to the PID file of this
 285                                 daemon. Use of this option is
 286                                 recommended for services where
 287                                 <varname>Type=</varname> is set to
 288                                 <option>forking</option>. systemd will
 289                                 read the PID of the main process of
 290                                 the daemon after start-up of the
 291                                 service. systemd will not write to the
 292                                 file configured here.</para>
 293                                 </listitem>
 294                         </varlistentry>
 295
 296                         <varlistentry>
 297                                 <term><varname>BusName=</varname></term>
 298
 299                                 <listitem><para>Takes a D-Bus bus
 300                                 name that this service is reachable
 301                                 as. This option is mandatory for
 302                                 services where
 303                                 <varname>Type=</varname> is set to
 304                                 <option>dbus</option>.</para>
 305                                 </listitem>
 306                         </varlistentry>
 307
 308                         <varlistentry>
 309                                 <term><varname>BusPolicy=</varname></term>
 310
 311                                 <listitem><para>If specified, a custom
 312                                 <ulink url="https://code.google.com/p/d-bus/">kdbus</ulink>
 313                                 endpoint will be created and installed as the
 314                                 default bus node for the service. Such a custom
 315                                 endpoint can hold an own set of policy rules
 316                                 that are enforced on top of the bus-wide ones.
 317                                 The custom endpoint is named after the service
 318                                 it was created for, and its node will be
 319                                 bind-mounted over the default bus node
 320                                 location, so the service can only access the
 321                                 bus through its own endpoint. Note that custom
 322                                 bus endpoints default to a 'deny all' policy.
 323                                 Hence, if at least one
 324                                 <varname>BusPolicy=</varname> directive is
 325                                 given, you have to make sure to add explicit
 326                                 rules for everything the service should be able
 327                                 to do.</para>
 328                                 <para>The value of this directive is comprised
 329                                 of two parts; the bus name, and a verb to
 330                                 specify to granted access, which is one of
 331                                 <option>see</option>,
 332                                 <option>talk</option>, or
 333                                 <option>own</option>.
 334                                 <option>talk</option> implies
 335                                 <option>see</option>, and <option>own</option>
 336                                 implies both <option>talk</option> and
 337                                 <option>see</option>.
 338                                 If multiple access levels are specified for the
 339                                 same bus name, the most powerful one takes
 340                                 effect.
 341                                 </para>
 342                                 <para>Examples:</para>
 343                                 <programlisting>BusPolicy=org.freedesktop.systemd1 talk</programlisting>
 344                                 <programlisting>BusPolicy=org.foo.bar see</programlisting>
 345                                 <para>This option is only available on kdbus enabled systems.</para>
 346                                 </listitem>
 347                         </varlistentry>
 348
 349                         <varlistentry>
 350                                 <term><varname>ExecStart=</varname></term>
 351                                 <listitem><para>Commands with their
 352                                 arguments that are executed when this
 353                                 service is started. The value is split
 354                                 into zero or more command lines is
 355                                 according to the rules described below
 356                                 (see section "Command Lines" below).
 357                                 </para>
 358
 359                                 <para>When <varname>Type</varname> is
 360                                 not <option>oneshot</option>, only one
 361                                 command may and must be given. When
 362                                 <varname>Type=oneshot</varname> is
 363                                 used, zero or more commands may be
 364                                 specified. This can be specified by
 365                                 providing multiple command lines in
 366                                 the same directive, or alternatively,
 367                                 this directive may be specified more
 368                                 than once with the same effect. If the
 369                                 empty string is assigned to this
 370                                 option, the list of commands to start
 371                                 is reset, prior assignments of this
 372                                 option will have no effect. If no
 373                                 <varname>ExecStart=</varname> is
 374                                 specified, then the service must have
 375                                 <varname>RemainAfterExit=yes</varname>
 376                                 set.</para>
 377
 378                                 <para>For each of the specified
 379                                 commands, the first argument must be
 380                                 an absolute and literal path to an
 381                                 executable. Optionally, if the
 382                                 absolute file name is prefixed with
 383                                 <literal>@</literal>, the second token
 384                                 will be passed as
 385                                 <literal>argv[0]</literal> to the
 386                                 executed process, followed by the
 387                                 further arguments specified. If the
 388                                 absolute filename is prefixed with
 389                                 <literal>-</literal>, an exit code of
 390                                 the command normally considered a
 391                                 failure (i.e. non-zero exit status or
 392                                 abnormal exit due to signal) is
 393                                 ignored and considered success. If
 394                                 both <literal>-</literal> and
 395                                 <literal>@</literal> are used, they
 396                                 can appear in either order.</para>
 397
 398                                 <para>If more than one command is
 399                                 specified, the commands are invoked
 400                                 sequentially in the order they appear
 401                                 in the unit file. If one of the
 402                                 commands fails (and is not prefixed
 403                                 with <literal>-</literal>), other
 404                                 lines are not executed, and the unit
 405                                 is considered failed.</para>
 406
 407                                 <para>Unless
 408                                 <varname>Type=forking</varname> is
 409                                 set, the process started via this
 410                                 command line will be considered the
 411                                 main process of the daemon.</para>
 412
 413                               </listitem>
 414                         </varlistentry>
 415
 416                         <varlistentry>
 417                                 <term><varname>ExecStartPre=</varname></term>
 418                                 <term><varname>ExecStartPost=</varname></term>
 419                                 <listitem><para>Additional commands
 420                                 that are executed before or after
 421                                 the command in
 422                                 <varname>ExecStart=</varname>, respectively.
 423                                 Syntax is the same as for
 424                                 <varname>ExecStart=</varname>, except
 425                                 that multiple command lines are allowed
 426                                 and the commands are executed one
 427                                 after the other, serially.</para>
 428
 429                                 <para>If any of those commands (not
 430                                 prefixed with <literal>-</literal>)
 431                                 fail, the rest are not executed and
 432                                 the unit is considered failed.</para>
 433                                 </listitem>
 434                         </varlistentry>
 435
 436                         <varlistentry>
 437                                 <term><varname>ExecReload=</varname></term>
 438                                 <listitem><para>Commands to execute to
 439                                 trigger a configuration reload in the
 440                                 service. This argument takes multiple
 441                                 command lines, following the same
 442                                 scheme as described for
 443                                 <varname>ExecStart=</varname>
 444                                 above. Use of this setting is
 445                                 optional. Specifier and environment
 446                                 variable substitution is supported
 447                                 here following the same scheme as for
 448                                 <varname>ExecStart=</varname>.</para>
 449
 450                                 <para>One additional, special
 451                                 environment variable is set: if known,
 452                                 <varname>$MAINPID</varname> is set to
 453                                 the main process of the daemon, and
 454                                 may be used for command lines like the
 455                                 following:</para>
 456
 457                                 <programlisting>/bin/kill -HUP $MAINPID</programlisting>
 458
 459                                 <para>Note however that reloading a
 460                                 daemon by sending a signal (as with
 461                                 the example line above) is usually not
 462                                 a good choice, because this is an
 463                                 asynchronous operation and hence not
 464                                 suitable to order reloads of multiple
 465                                 services against each other. It is
 466                                 strongly recommended to set
 467                                 <varname>ExecReload=</varname> to a
 468                                 command that not only triggers a
 469                                 configuration reload of the daemon,
 470                                 but also synchronously waits for it to
 471                                 complete.</para>
 472                                 </listitem>
 473                         </varlistentry>
 474
 475                         <varlistentry>
 476                                 <term><varname>ExecStop=</varname></term>
 477                                 <listitem><para>Commands to execute to
 478                                 stop the service started via
 479                                 <varname>ExecStart=</varname>. This
 480                                 argument takes multiple command lines,
 481                                 following the same scheme as described
 482                                 for <varname>ExecStart=</varname>
 483                                 above. Use of this setting is
 484                                 optional. After the commands configured
 485                                 in this option are run, all processes
 486                                 remaining for a service are
 487                                 terminated according to the
 488                                 <varname>KillMode=</varname> setting
 489                                 (see
 490                                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>). If
 491                                 this option is not specified, the
 492                                 process is terminated immediately when
 493                                 service stop is requested. Specifier
 494                                 and environment variable substitution
 495                                 is supported (including
 496                                 <varname>$MAINPID</varname>, see
 497                                 above).</para></listitem>
 498                         </varlistentry>
 499
 500                         <varlistentry>
 501                                 <term><varname>ExecStopPost=</varname></term>
 502                                 <listitem><para>Additional commands
 503                                 that are executed after the service
 504                                 was stopped. This includes cases where
 505                                 the commands configured in
 506                                 <varname>ExecStop=</varname> were used,
 507                                 where the service does not have any
 508                                 <varname>ExecStop=</varname> defined, or
 509                                 where the service exited unexpectedly. This
 510                                 argument takes multiple command lines,
 511                                 following the same scheme as described
 512                                 for <varname>ExecStart</varname>. Use
 513                                 of these settings is
 514                                 optional. Specifier and environment
 515                                 variable substitution is
 516                                 supported.</para></listitem>
 517                         </varlistentry>
 518
 519                         <varlistentry>
 520                                 <term><varname>RestartSec=</varname></term>
 521                                 <listitem><para>Configures the time to
 522                                 sleep before restarting a service (as
 523                                 configured with
 524                                 <varname>Restart=</varname>). Takes a
 525                                 unit-less value in seconds, or a time
 526                                 span value such as "5min
 527                                 20s". Defaults to
 528                                 100ms.</para></listitem>
 529                         </varlistentry>
 530
 531                         <varlistentry>
 532                                 <term><varname>TimeoutStartSec=</varname></term>
 533                                 <listitem><para>Configures the time to
 534                                 wait for start-up. If a
 535                                 daemon service does not signal
 536                                 start-up completion within the
 537                                 configured time, the service will be
 538                                 considered failed and will be shut
 539                                 down again.
 540                                 Takes a unit-less value in seconds, or a
 541                                 time span value such as "5min
 542                                 20s". Pass <literal>0</literal> to
 543                                 disable the timeout logic. Defaults to
 544                                 <varname>DefaultTimeoutStartSec=</varname> from
 545                                 the manager configuration file, except
 546                                 when <varname>Type=oneshot</varname> is
 547                                 used, in which case the timeout
 548                                 is disabled by default
 549                                 (see <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 550                                 </para></listitem>
 551                         </varlistentry>
 552
 553                         <varlistentry>
 554                                 <term><varname>TimeoutStopSec=</varname></term>
 555                                 <listitem><para>Configures the time to
 556                                 wait for stop. If a service is asked
 557                                 to stop, but does not terminate in the
 558                                 specified time, it will be terminated
 559                                 forcibly via <constant>SIGTERM</constant>,
 560                                 and after another timeout of equal duration
 561                                 with <constant>SIGKILL</constant> (see
 562                                 <varname>KillMode=</varname>
 563                                 in <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 564                                 Takes a unit-less value in seconds, or a
 565                                 time span value such as "5min
 566                                 20s". Pass <literal>0</literal> to disable
 567                                 the timeout logic. Defaults to
 568                                 <varname>DefaultTimeoutStopSec=</varname> from the
 569                                 manager configuration file
 570                                 (see <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 571                                 </para></listitem>
 572                         </varlistentry>
 573
 574                         <varlistentry>
 575                                 <term><varname>TimeoutSec=</varname></term>
 576                                 <listitem><para>A shorthand for configuring
 577                                 both <varname>TimeoutStartSec=</varname>
 578                                 and <varname>TimeoutStopSec=</varname>
 579                                 to the specified value.
 580                                 </para></listitem>
 581                         </varlistentry>
 582
 583                         <varlistentry>
 584                                 <term><varname>WatchdogSec=</varname></term>
 585                                 <listitem><para>Configures the
 586                                 watchdog timeout for a service. The
 587                                 watchdog is activated when the start-up is
 588                                 completed. The service must call
 589                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 590                                 regularly with <literal>WATCHDOG=1</literal>
 591                                 (i.e. the "keep-alive ping"). If the time
 592                                 between two such calls is larger than
 593                                 the configured time, then the service
 594                                 is placed in a failed state and it will
 595                                 be terminated with <varname>SIGABRT</varname>.
 596                                 By setting <varname>Restart=</varname> to
 597                                 <option>on-failure</option> or
 598                                 <option>always</option>, the service
 599                                 will be automatically restarted. The
 600                                 time configured here will be passed to
 601                                 the executed service process in the
 602                                 <varname>WATCHDOG_USEC=</varname>
 603                                 environment variable. This allows
 604                                 daemons to automatically enable the
 605                                 keep-alive pinging logic if watchdog
 606                                 support is enabled for the service. If
 607                                 this option is used,
 608                                 <varname>NotifyAccess=</varname> (see
 609                                 below) should be set to open access to
 610                                 the notification socket provided by
 611                                 systemd. If
 612                                 <varname>NotifyAccess=</varname> is
 613                                 not set, it will be implicitly set to
 614                                 <option>main</option>. Defaults to 0,
 615                                 which disables this
 616                                 feature.</para></listitem>
 617                         </varlistentry>
 618
 619                         <varlistentry>
 620                                 <term><varname>Restart=</varname></term>
 621                                 <listitem><para>Configures whether the
 622                                 service shall be restarted when the
 623                                 service process exits, is killed,
 624                                 or a timeout is reached. The service
 625                                 process may be the main service
 626                                 process, but it may also be one of the
 627                                 processes specified with
 628                                 <varname>ExecStartPre=</varname>,
 629                                 <varname>ExecStartPost=</varname>,
 630                                 <varname>ExecStop=</varname>,
 631                                 <varname>ExecStopPost=</varname>, or
 632                                 <varname>ExecReload=</varname>.
 633                                 When the death of the process is a
 634                                 result of systemd operation (e.g. service
 635                                 stop or restart), the service will not be
 636                                 restarted. Timeouts include missing
 637                                 the watchdog "keep-alive ping"
 638                                 deadline and a service start, reload,
 639                                 and stop operation timeouts.</para>
 640
 641                                 <para>Takes one of
 642                                 <option>no</option>,
 643                                 <option>on-success</option>,
 644                                 <option>on-failure</option>,
 645                                 <option>on-abnormal</option>,
 646                                 <option>on-watchdog</option>,
 647                                 <option>on-abort</option>, or
 648                                 <option>always</option>. If set to
 649                                 <option>no</option> (the default), the
 650                                 service will not be restarted. If set
 651                                 to <option>on-success</option>, it
 652                                 will be restarted only when the
 653                                 service process exits cleanly.  In
 654                                 this context, a clean exit means an
 655                                 exit code of 0, or one of the signals
 656                                 <constant>SIGHUP</constant>,
 657                                 <constant>SIGINT</constant>,
 658                                 <constant>SIGTERM</constant> or
 659                                 <constant>SIGPIPE</constant>, and
 660                                 additionally, exit statuses and
 661                                 signals specified in
 662                                 <varname>SuccessExitStatus=</varname>.
 663                                 If set to <option>on-failure</option>,
 664                                 the service will be restarted when the
 665                                 process exits with a non-zero exit
 666                                 code, is terminated by a signal
 667                                 (including on core dump, but excluding
 668                                 the aforementiond four signals), when
 669                                 an operation (such as service reload)
 670                                 times out, and when the configured
 671                                 watchdog timeout is triggered.  If set
 672                                 to <option>on-abnormal</option>, the
 673                                 service will be restarted when the
 674                                 process is terminated by a signal
 675                                 (including on core dump, excluding the
 676                                 aforementioned four signals), when an
 677                                 operation times out, or when the
 678                                 watchdog timeout is triggered. If set
 679                                 to <option>on-abort</option>, the
 680                                 service will be restarted only if the
 681                                 service process exits due to an
 682                                 uncaught signal not specified as a
 683                                 clean exit status.  If set to
 684                                 <option>on-watchdog</option>, the
 685                                 service will be restarted only if the
 686                                 watchdog timeout for the service
 687                                 expires.  If set to
 688                                 <option>always</option>, the service
 689                                 will be restarted regardless of
 690                                 whether it exited cleanly or not, got
 691                                 terminated abnormally by a signal, or
 692                                 hit a timeout.</para>
 693
 694                                 <table>
 695                                         <title>Exit causes and the effect of the <varname>Restart=</varname> settings on them</title>
 696
 697                                         <tgroup cols='2'>
 698                                                 <colspec colname='path' />
 699                                                 <colspec colname='expl' />
 700                                                 <thead>
 701                                                         <row>
 702                                                                 <entry>Restart settings/Exit causes</entry>
 703                                                                 <entry><option>no</option></entry>
 704                                                                 <entry><option>always</option></entry>
 705                                                                 <entry><option>on-success</option></entry>
 706                                                                 <entry><option>on-failure</option></entry>
 707                                                                 <entry><option>on-abnormal</option></entry>
 708                                                                 <entry><option>on-abort</option></entry>
 709                                                                 <entry><option>on-watchdog</option></entry>
 710                                                         </row>
 711                                                 </thead>
 712                                                 <tbody>
 713                                                         <row>
 714                                                                 <entry>Clean exit code or signal</entry>
 715                                                                 <entry/>
 716                                                                 <entry>X</entry>
 717                                                                 <entry>X</entry>
 718                                                                 <entry/>
 719                                                                 <entry/>
 720                                                                 <entry/>
 721                                                                 <entry/>
 722                                                         </row>
 723                                                         <row>
 724                                                                 <entry>Unclean exit code</entry>
 725                                                                 <entry/>
 726                                                                 <entry>X</entry>
 727                                                                 <entry/>
 728                                                                 <entry>X</entry>
 729                                                                 <entry/>
 730                                                                 <entry/>
 731                                                                 <entry/>
 732                                                         </row>
 733                                                         <row>
 734                                                                 <entry>Unclean signal</entry>
 735                                                                 <entry/>
 736                                                                 <entry>X</entry>
 737                                                                 <entry/>
 738                                                                 <entry>X</entry>
 739                                                                 <entry>X</entry>
 740                                                                 <entry>X</entry>
 741                                                                 <entry/>
 742                                                         </row>
 743                                                         <row>
 744                                                                 <entry>Timeout</entry>
 745                                                                 <entry/>
 746                                                                 <entry>X</entry>
 747                                                                 <entry/>
 748                                                                 <entry>X</entry>
 749                                                                 <entry>X</entry>
 750                                                                 <entry/>
 751                                                                 <entry/>
 752                                                         </row>
 753                                                         <row>
 754                                                                 <entry>Watchdog</entry>
 755                                                                 <entry/>
 756                                                                 <entry>X</entry>
 757                                                                 <entry/>
 758                                                                 <entry>X</entry>
 759                                                                 <entry>X</entry>
 760                                                                 <entry/>
 761                                                                 <entry>X</entry>
 762                                                         </row>
 763                                                 </tbody>
 764                                         </tgroup>
 765                                 </table>
 766
 767                                 <para>As exceptions to the setting
 768                                 above the service will not be
 769                                 restarted if the exit code or signal
 770                                 is specified in
 771                                 <varname>RestartPreventExitStatus=</varname>
 772                                 (see below). Also, the services will
 773                                 always be restarted if the exit code
 774                                 or signal is specified in
 775                                 <varname>RestartForceExitStatus=</varname>
 776                                 (see below).</para>
 777
 778                                 <para>Setting this to
 779                                 <option>on-failure</option> is the
 780                                 recommended choice for long-running
 781                                 services, in order to increase
 782                                 reliability by attempting automatic
 783                                 recovery from errors. For services
 784                                 that shall be able to terminate on
 785                                 their own choice (and avoid
 786                                 immediate restarting),
 787                                 <option>on-abnormal</option> is an
 788                                 alternative choice.</para>
 789                                 </listitem>
 790                         </varlistentry>
 791
 792                         <varlistentry>
 793                                 <term><varname>SuccessExitStatus=</varname></term>
 794                                 <listitem><para>Takes a list of exit
 795                                 status definitions that when returned
 796                                 by the main service process will be
 797                                 considered successful termination, in
 798                                 addition to the normal successful exit
 799                                 code 0 and the signals <constant>SIGHUP</constant>, <constant>SIGINT</constant>,
 800                                 <constant>SIGTERM</constant>, and <constant>SIGPIPE</constant>. Exit status
 801                                 definitions can either be numeric exit
 802                                 codes or termination signal names,
 803                                 separated by spaces. For example:
 804                                 <programlisting>SuccessExitStatus=1 2 8 SIGKILL</programlisting>
 805                                 ensures that exit codes 1, 2, 8 and
 806                                 the termination signal
 807                                 <constant>SIGKILL</constant> are
 808                                 considered clean service terminations.
 809                                 </para>
 810
 811                                 <para>Note that if a process has a
 812                                 signal handler installed and exits by
 813                                 calling
 814                                 <citerefentry><refentrytitle>_exit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 815                                 in response to a signal, the
 816                                 information about the signal is lost.
 817                                 Programs should instead perform cleanup and kill themselves with the same signal instead. See
 818                                 <ulink url="http://www.cons.org/cracauer/sigint.html">Proper handling of SIGINT/SIGQUIT — How to be a proper program</ulink>.</para>
 819
 820                                 <para>This option may appear more than once,
 821                                 in which case the list of successful
 822                                 exit statuses is merged. If the empty
 823                                 string is assigned to this option, the
 824                                 list is reset, all prior assignments
 825                                 of this option will have no
 826                                 effect.</para></listitem>
 827                         </varlistentry>
 828
 829                         <varlistentry>
 830                                 <term><varname>RestartPreventExitStatus=</varname></term>
 831                                 <listitem><para>Takes a list of exit
 832                                 status definitions that when returned
 833                                 by the main service process will
 834                                 prevent automatic service restarts,
 835                                 regardless of the restart setting
 836                                 configured with
 837                                 <varname>Restart=</varname>. Exit
 838                                 status definitions can either be
 839                                 numeric exit codes or termination
 840                                 signal names, and are separated by
 841                                 spaces. Defaults to the empty list, so
 842                                 that, by default, no exit status is
 843                                 excluded from the configured restart
 844                                 logic. For example:
 845                                 <programlisting>RestartPreventExitStatus=1 6 SIGABRT</programlisting> ensures that exit
 846                                 codes 1 and 6 and the termination
 847                                 signal <constant>SIGABRT</constant> will
 848                                 not result in automatic service
 849                                 restarting. This
 850                                 option may appear more than once, in
 851                                 which case the list of restart-preventing
 852                                 statuses is merged. If the empty
 853                                 string is assigned to this option, the
 854                                 list is reset and all prior assignments
 855                                 of this option will have no
 856                                 effect.</para></listitem>
 857                         </varlistentry>
 858
 859                         <varlistentry>
 860                                 <term><varname>RestartForceExitStatus=</varname></term>
 861                                 <listitem><para>Takes a list of exit
 862                                 status definitions that when returned
 863                                 by the main service process will force
 864                                 automatic service restarts, regardless
 865                                 of the restart setting configured with
 866                                 <varname>Restart=</varname>. The
 867                                 argument format is similar to
 868                                 <varname>RestartPreventExitStatus=</varname>.</para></listitem>
 869                         </varlistentry>
 870
 871                         <varlistentry>
 872                                 <term><varname>PermissionsStartOnly=</varname></term>
 873                                 <listitem><para>Takes a boolean
 874                                 argument. If true, the permission-related
 875                                 execution options, as
 876                                 configured with
 877                                 <varname>User=</varname> and similar
 878                                 options (see
 879                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 880                                 for more information), are only applied
 881                                 to the process started with
 882                                 <varname>ExecStart=</varname>, and not
 883                                 to the various other
 884                                 <varname>ExecStartPre=</varname>,
 885                                 <varname>ExecStartPost=</varname>,
 886                                 <varname>ExecReload=</varname>,
 887                                 <varname>ExecStop=</varname>, and
 888                                 <varname>ExecStopPost=</varname>
 889                                 commands. If false, the setting is
 890                                 applied to all configured commands the
 891                                 same way. Defaults to
 892                                 false.</para></listitem>
 893                         </varlistentry>
 894
 895                         <varlistentry>
 896                                 <term><varname>RootDirectoryStartOnly=</varname></term>
 897                                 <listitem><para>Takes a boolean
 898                                 argument. If true, the root directory,
 899                                 as configured with the
 900                                 <varname>RootDirectory=</varname>
 901                                 option (see
 902                                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 903                                 for more information), is only applied
 904                                 to the process started with
 905                                 <varname>ExecStart=</varname>, and not
 906                                 to the various other
 907                                 <varname>ExecStartPre=</varname>,
 908                                 <varname>ExecStartPost=</varname>,
 909                                 <varname>ExecReload=</varname>,
 910                                 <varname>ExecStop=</varname>, and
 911                                 <varname>ExecStopPost=</varname>
 912                                 commands. If false, the setting is
 913                                 applied to all configured commands the
 914                                 same way. Defaults to
 915                                 false.</para></listitem>
 916                         </varlistentry>
 917
 918                         <varlistentry>
 919                                 <term><varname>NonBlocking=</varname></term>
 920                                 <listitem><para>Set the
 921                                 <constant>O_NONBLOCK</constant> flag
 922                                 for all file descriptors passed via
 923                                 socket-based activation. If true, all
 924                                 file descriptors >= 3 (i.e. all except
 925                                 stdin, stdout, and stderr) will have
 926                                 the <constant>O_NONBLOCK</constant> flag
 927                                 set and hence are in
 928                                 non-blocking mode. This option is only
 929                                 useful in conjunction with a socket
 930                                 unit, as described in
 931                                 <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Defaults
 932                                 to false.</para></listitem>
 933                         </varlistentry>
 934
 935                         <varlistentry>
 936                                 <term><varname>NotifyAccess=</varname></term>
 937                                 <listitem><para>Controls access to the
 938                                 service status notification socket, as
 939                                 accessible via the
 940                                 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 941                                 call. Takes one of
 942                                 <option>none</option> (the default),
 943                                 <option>main</option> or
 944                                 <option>all</option>. If
 945                                 <option>none</option>, no daemon status
 946                                 updates are accepted from the service
 947                                 processes, all status update messages
 948                                 are ignored. If <option>main</option>,
 949                                 only service updates sent from the
 950                                 main process of the service are
 951                                 accepted. If <option>all</option>, all
 952                                 services updates from all members of
 953                                 the service's control group are
 954                                 accepted. This option should be set to
 955                                 open access to the notification socket
 956                                 when using
 957                                 <varname>Type=notify</varname> or
 958                                 <varname>WatchdogSec=</varname> (see
 959                                 above). If those options are used but
 960                                 <varname>NotifyAccess=</varname> is not
 961                                 configured, it will be implicitly set
 962                                 to
 963                                 <option>main</option>.</para></listitem>
 964                         </varlistentry>
 965
 966                         <varlistentry>
 967                                 <term><varname>Sockets=</varname></term>
 968                                 <listitem><para>Specifies the name of
 969                                 the socket units this service shall
 970                                 inherit socket file descriptors
 971                                 from when the service is
 972                                 started. Normally it should not be
 973                                 necessary to use this setting as all
 974                                 socket file descriptors whose unit
 975                                 shares the same name as the service
 976                                 (subject to the different unit name
 977                                 suffix of course) are passed to the
 978                                 spawned process.</para>
 979
 980                                 <para>Note that the same socket file
 981                                 descriptors may be passed to multiple
 982                                 processes simultaneously. Also note
 983                                 that a different service may be
 984                                 activated on incoming socket traffic
 985                                 than the one which is ultimately
 986                                 configured to inherit the socket file
 987                                 descriptors. Or in other words: the
 988                                 <varname>Service=</varname> setting of
 989                                 <filename>.socket</filename> units
 990                                 does not have to match the inverse of
 991                                 the <varname>Sockets=</varname>
 992                                 setting of the
 993                                 <filename>.service</filename> it
 994                                 refers to.</para>
 995
 996                                 <para>This option may appear more than
 997                                 once, in which case the list of socket
 998                                 units is merged. If the empty string
 999                                 is assigned to this option, the list of
1000                                 sockets is reset, and all prior uses of
1001                                 this setting will have no
1002                                 effect.</para></listitem>
1003                         </varlistentry>
1004
1005                         <varlistentry>
1006                                 <term><varname>StartLimitInterval=</varname></term>
1007                                 <term><varname>StartLimitBurst=</varname></term>
1008
1009                                 <listitem><para>Configure service
1010                                 start rate limiting. By default,
1011                                 services which are started more
1012                                 than 5 times within 10 seconds are not
1013                                 permitted to start any more times
1014                                 until the 10 second interval ends. With
1015                                 these two options, this rate limiting
1016                                 may be modified. Use
1017                                 <varname>StartLimitInterval=</varname>
1018                                 to configure the checking interval (defaults to
1019                                 <varname>DefaultStartLimitInterval=</varname> in
1020                                 manager configuration file, set to 0 to disable
1021                                 any kind of rate limiting). Use
1022                                 <varname>StartLimitBurst=</varname> to
1023                                 configure how many starts per interval
1024                                 are allowed (defaults to
1025                                 <varname>DefaultStartLimitBurst=</varname> in
1026                                 manager configuration file). These
1027                                 configuration options are particularly
1028                                 useful in conjunction with
1029                                 <varname>Restart=</varname>; however,
1030                                 they apply to all kinds of starts
1031                                 (including manual), not just those
1032                                 triggered by the
1033                                 <varname>Restart=</varname> logic.
1034                                 Note that units which are configured
1035                                 for <varname>Restart=</varname> and
1036                                 which reach the start limit are not
1037                                 attempted to be restarted anymore;
1038                                 however, they may still be restarted
1039                                 manually at a later point, from which
1040                                 point on, the restart logic is again
1041                                 activated. Note that
1042                                 <command>systemctl
1043                                 reset-failed</command> will cause the
1044                                 restart rate counter for a service to
1045                                 be flushed, which is useful if the
1046                                 administrator wants to manually start
1047                                 a service and the start limit
1048                                 interferes with
1049                                 that.</para></listitem>
1050                         </varlistentry>
1051
1052                         <varlistentry>
1053                                 <term><varname>StartLimitAction=</varname></term>
1054
1055                                 <listitem><para>Configure the action
1056                                 to take if the rate limit configured
1057                                 with
1058                                 <varname>StartLimitInterval=</varname>
1059                                 and
1060                                 <varname>StartLimitBurst=</varname> is
1061                                 hit. Takes one of
1062                                 <option>none</option>,
1063                                 <option>reboot</option>,
1064                                 <option>reboot-force</option>,
1065                                 <option>reboot-immediate</option>,
1066                                 <option>poweroff</option>,
1067                                 <option>poweroff-force</option> or
1068                                 <option>poweroff-immediate</option>. If
1069                                 <option>none</option> is set, hitting
1070                                 the rate limit will trigger no action
1071                                 besides that the start will not be
1072                                 permitted. <option>reboot</option>
1073                                 causes a reboot following the normal
1074                                 shutdown procedure (i.e. equivalent to
1075                                 <command>systemctl reboot</command>).
1076                                 <option>reboot-force</option> causes a
1077                                 forced reboot which will terminate all
1078                                 processes forcibly but should cause no
1079                                 dirty file systems on reboot
1080                                 (i.e. equivalent to <command>systemctl
1081                                 reboot -f</command>) and
1082                                 <option>reboot-immediate</option>
1083                                 causes immediate execution of the
1084                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1085                                 system call, which might result in
1086                                 data loss. Similar,
1087                                 <option>poweroff</option>,
1088                                 <option>poweroff-force</option>,
1089                                 <option>poweroff-immediate</option>
1090                                 have the effect of powering down the
1091                                 system with similar
1092                                 semantics. Defaults to
1093                                 <option>none</option>.</para></listitem>
1094                         </varlistentry>
1095
1096                         <varlistentry>
1097                                 <term><varname>FailureAction=</varname></term>
1098                                 <listitem><para>Configure the action
1099                                 to take when the service enters a failed
1100                                 state. Takes the same values as
1101                                 <varname>StartLimitAction=</varname>
1102                                 and executes the same actions.
1103                                 Defaults to <option>none</option>.
1104                                 </para></listitem>
1105                         </varlistentry>
1106
1107                         <varlistentry>
1108                                 <term><varname>RebootArgument=</varname></term>
1109                                 <listitem><para>Configure the optional
1110                                 argument for the
1111                                 <citerefentry><refentrytitle>reboot</refentrytitle><manvolnum>2</manvolnum></citerefentry>
1112                                 system call if
1113                                 <varname>StartLimitAction=</varname>
1114                                 or <varname>FailureAction=</varname>
1115                                 is a reboot action. This works just
1116                                 like the optional argument to
1117                                 <command>systemctl reboot</command>
1118                                 command.</para></listitem>
1119                         </varlistentry>
1120
1121                 </variablelist>
1122
1123                 <para>Check
1124                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1125                 and
1126                 <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>
1127                 for more settings.</para>
1128
1129         </refsect1>
1130
1131         <refsect1>
1132                 <title>Command lines</title>
1133
1134                 <para>This section describes command line parsing and
1135                 variable and specifier substitions for
1136                 <varname>ExecStart=</varname>,
1137                 <varname>ExecStartPre=</varname>,
1138                 <varname>ExecStartPost=</varname>,
1139                 <varname>ExecReload=</varname>,
1140                 <varname>ExecStop=</varname>, and
1141                 <varname>ExecStopPost=</varname> options.</para>
1142
1143                 <para>Multiple command lines may be concatenated in a
1144                 single directive by separating them with semicolons
1145                 (these semicolons must be passed as separate words).
1146                 Lone semicolons may be escaped as
1147                 <literal>\;</literal>.</para>
1148
1149                 <para>Each command line is split on whitespace, with
1150                 the first item being the command to execute, and the
1151                 subsequent items being the arguments.  Double quotes
1152                 ("...") and single quotes ('...') may be used, in
1153                 which case everything until the next matching quote
1154                 becomes part of the same argument. Quotes themselves
1155                 are removed after parsing. In addition, a trailing
1156                 backslash (<literal>\</literal>) may be used to merge
1157                 lines. </para>
1158
1159                 <para>This syntax is intended to be very similar to
1160                 shell syntax, but only the meta-characters and
1161                 expansions described in the following paragraphs are
1162                 understood.  Specifically, redirection using
1163                 <literal>&lt;</literal>, <literal>&lt;&lt;</literal>,
1164                 <literal>&gt;</literal>, and
1165                 <literal>&gt;&gt;</literal>, pipes using
1166                 <literal>|</literal>, running programs in the
1167                 background using <literal>&amp;</literal>, and
1168                 <emphasis>other elements of shell syntax are not
1169                 supported</emphasis>.</para>
1170
1171                 <para>The command line accepts <literal>%</literal>
1172                 specifiers as described in
1173                 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
1174                 Note that the first argument of the command line
1175                 (i.e. the program to execute) may not include
1176                 specifiers.</para>
1177
1178                 <para>Basic environment variable substitution is
1179                 supported. Use <literal>${FOO}</literal> as part of a
1180                 word, or as a word of its own, on the command line, in
1181                 which case it will be replaced by the value of the
1182                 environment variable including all whitespace it
1183                 contains, resulting in a single argument. Use
1184                 <literal>$FOO</literal> as a separate word on the
1185                 command line, in which case it will be replaced by the
1186                 value of the environment variable split at whitespace
1187                 resulting in zero or more arguments. For this type of
1188                 expansion, quotes and respected when splitting into
1189                 words, and afterwards removed.</para>
1190
1191                 <para>Example:</para>
1192
1193                 <programlisting>Environment="ONE=one" 'TWO=two two'
1194 ExecStart=/bin/echo $ONE $TWO ${TWO}</programlisting>
1195
1196                 <para>This will execute <command>/bin/echo</command>
1197                 with four arguments: <literal>one</literal>,
1198                 <literal>two</literal>, <literal>two</literal>, and
1199                 <literal>two two</literal>.</para>
1200
1201                 <para>Example:</para>
1202                 <programlisting>Environment=ONE='one' "TWO='two two' too" THREE=
1203 ExecStart=/bin/echo ${ONE} ${TWO} ${THREE}
1204 ExecStart=/bin/echo $ONE $TWO $THREE</programlisting>
1205                 <para>This results in <filename>echo</filename> being
1206                 called twice, the first time with arguments
1207                 <literal>'one'</literal>,
1208                 <literal>'two two' too</literal>, <literal></literal>,
1209                 and the second time with arguments
1210                 <literal>one</literal>, <literal>two two</literal>,
1211                 <literal>too</literal>.
1212                 </para>
1213
1214                 <para>To pass a literal dollar sign, use
1215                 <literal>$$</literal>. Variables whose value is not
1216                 known at expansion time are treated as empty
1217                 strings. Note that the first argument (i.e. the
1218                 program to execute) may not be a variable.</para>
1219
1220                 <para>Variables to be used in this fashion may be
1221                 defined through <varname>Environment=</varname> and
1222                 <varname>EnvironmentFile=</varname>.  In addition,
1223                 variables listed in the section "Environment variables
1224                 in spawned processes" in
1225                 <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1226                 which are considered "static configuration", may be
1227                 used (this includes e.g. <varname>$USER</varname>, but
1228                 not <varname>$TERM</varname>).</para>
1229
1230                 <para>Note that shell command lines are not directly
1231                 supported. If shell command lines are to be used, they
1232                 need to be passed explicitly to a shell implementation
1233                 of some kind. Example:</para>
1234                 <programlisting>ExecStart=/bin/sh -c 'dmesg | tac'</programlisting>
1235
1236                 <para>Example:</para>
1237
1238                 <programlisting>ExecStart=/bin/echo one ; /bin/echo "two two"</programlisting>
1239
1240                 <para>This will execute <command>/bin/echo</command>
1241                 two times, each time with one argument:
1242                 <literal>one</literal> and <literal>two two</literal>,
1243                 respectively. Because two commands are specified,
1244                 <varname>Type=oneshot</varname> must be used.</para>
1245
1246                 <para>Example:</para>
1247
1248                 <programlisting>ExecStart=/bin/echo / &gt;/dev/null &amp; \; \
1249 /bin/ls</programlisting>
1250
1251                 <para>This will execute <command>/bin/echo</command>
1252                 with five arguments: <literal>/</literal>,
1253                 <literal>&gt;/dev/null</literal>,
1254                 <literal>&amp;</literal>, <literal>;</literal>, and
1255                 <literal>/bin/ls</literal>.</para>
1256         </refsect1>
1257
1258         <refsect1>
1259                   <title>See Also</title>
1260                   <para>
1261                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1262                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
1263                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1264                           <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1265                           <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1266                           <citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
1267                           <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
1268                   </para>
1269         </refsect1>
1270
1271 </refentry>