man/systemd-system.conf.xml

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  10   Copyright 2010 Lennart Poettering
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  25
  26 <refentry id="systemd-system.conf"
  27     xmlns:xi="http://www.w3.org/2001/XInclude">
  28   <refentryinfo>
  29     <title>systemd-system.conf</title>
  30     <productname>systemd</productname>
  31
  32     <authorgroup>
  33       <author>
  34         <contrib>Developer</contrib>
  35         <firstname>Lennart</firstname>
  36         <surname>Poettering</surname>
  37         <email>lennart@poettering.net</email>
  38       </author>
  39     </authorgroup>
  40   </refentryinfo>
  41
  42   <refmeta>
  43     <refentrytitle>systemd-system.conf</refentrytitle>
  44     <manvolnum>5</manvolnum>
  45   </refmeta>
  46
  47   <refnamediv>
  48     <refname>systemd-system.conf</refname>
  49     <refname>system.conf.d</refname>
  50     <refname>systemd-user.conf</refname>
  51     <refname>user.conf.d</refname>
  52     <refpurpose>System and session service manager configuration files</refpurpose>
  53   </refnamediv>
  54
  55   <refsynopsisdiv>
  56     <para><filename>/etc/systemd/system.conf</filename>,
  57     <filename>/etc/systemd/system.conf.d/*.conf</filename>,
  58     <filename>/run/systemd/system.conf.d/*.conf</filename>,
  59     <filename>/usr/lib/systemd/system.conf.d/*.conf</filename></para>
  60     <para><filename>/etc/systemd/user.conf</filename>,
  61     <filename>/etc/systemd/user.conf.d/*.conf</filename>,
  62     <filename>/run/systemd/user.conf.d/*.conf</filename>,
  63     <filename>/usr/lib/systemd/user.conf.d/*.conf</filename></para>
  64   </refsynopsisdiv>
  65
  66   <refsect1>
  67     <title>Description</title>
  68
  69     <para>When run as a system instance, systemd interprets the
  70     configuration file <filename>system.conf</filename> and the files
  71     in <filename>system.conf.d</filename> directories; when run as a
  72     user instance, systemd interprets the configuration file
  73     <filename>user.conf</filename> and the files in
  74     <filename>user.conf.d</filename> directories. These configuration
  75     files contain a few settings controlling basic manager
  76     operations.</para>
  77   </refsect1>
  78
  79   <xi:include href="standard-conf.xml" xpointer="main-conf" />
  80
  81   <refsect1>
  82     <title>Options</title>
  83
  84     <para>All options are configured in the
  85     <literal>[Manager]</literal> section:</para>
  86
  87     <variablelist class='systemd-directives'>
  88
  89       <varlistentry>
  90         <term><varname>LogLevel=</varname></term>
  91         <term><varname>LogTarget=</varname></term>
  92         <term><varname>LogColor=</varname></term>
  93         <term><varname>LogLocation=</varname></term>
  94         <term><varname>DumpCore=yes</varname></term>
  95         <term><varname>CrashChangeVT=no</varname></term>
  96         <term><varname>CrashShell=no</varname></term>
  97         <term><varname>CrashReboot=no</varname></term>
  98         <term><varname>ShowStatus=yes</varname></term>
  99         <term><varname>DefaultStandardOutput=journal</varname></term>
 100         <term><varname>DefaultStandardError=inherit</varname></term>
 101
 102         <listitem><para>Configures various parameters of basic manager operation. These options may be overridden by
 103         the respective process and kernel command line arguments. See
 104         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> for
 105         details.</para></listitem>
 106       </varlistentry>
 107
 108       <varlistentry>
 109         <term><varname>CtrlAltDelBurstAction=</varname></term>
 110
 111         <listitem><para>Defines what action will be performed
 112         if user presses Ctrl-Alt-Delete more than 7 times in 2s.
 113         Can be set to <literal>reboot-force</literal>, <literal>poweroff-force</literal>,
 114         <literal>reboot-immediate</literal>, <literal>poweroff-immediate</literal>
 115         or disabled with <literal>none</literal>. Defaults to
 116         <literal>reboot-force</literal>.
 117         </para></listitem>
 118       </varlistentry>
 119
 120       <varlistentry>
 121         <term><varname>CPUAffinity=</varname></term>
 122
 123         <listitem><para>Configures the initial CPU affinity for the
 124         init process. Takes a list of CPU indices or ranges separated
 125         by either whitespace or commas. CPU ranges are specified by
 126         the lower and upper CPU indices separated by a
 127         dash.</para></listitem>
 128       </varlistentry>
 129
 130       <varlistentry>
 131         <term><varname>JoinControllers=cpu,cpuacct net_cls,netprio</varname></term>
 132
 133         <listitem><para>Configures controllers that shall be mounted
 134         in a single hierarchy. By default, systemd will mount all
 135         controllers which are enabled in the kernel in individual
 136         hierarchies, with the exception of those listed in this
 137         setting. Takes a space-separated list of comma-separated
 138         controller names, in order to allow multiple joined
 139         hierarchies. Defaults to 'cpu,cpuacct'. Pass an empty string
 140         to ensure that systemd mounts all controllers in separate
 141         hierarchies.</para>
 142
 143         <para>Note that this option is only applied once, at very
 144         early boot. If you use an initial RAM disk (initrd) that uses
 145         systemd, it might hence be necessary to rebuild the initrd if
 146         this option is changed, and make sure the new configuration
 147         file is included in it. Otherwise, the initrd might mount the
 148         controller hierarchies in a different configuration than
 149         intended, and the main system cannot remount them
 150         anymore.</para></listitem>
 151       </varlistentry>
 152
 153       <varlistentry>
 154         <term><varname>RuntimeWatchdogSec=</varname></term>
 155         <term><varname>ShutdownWatchdogSec=</varname></term>
 156
 157         <listitem><para>Configure the hardware watchdog at runtime and
 158         at reboot. Takes a timeout value in seconds (or in other time
 159         units if suffixed with <literal>ms</literal>,
 160         <literal>min</literal>, <literal>h</literal>,
 161         <literal>d</literal>, <literal>w</literal>). If
 162         <varname>RuntimeWatchdogSec=</varname> is set to a non-zero
 163         value, the watchdog hardware
 164         (<filename>/dev/watchdog</filename> or the path specified with
 165         <varname>WatchdogDevice=</varname> or the kernel option
 166         <varname>systemd.watchdog-device=</varname>) will be programmed
 167         to automatically reboot the system if it is not contacted within
 168         the specified timeout interval. The system manager will ensure
 169         to contact it at least once in half the specified timeout
 170         interval. This feature requires a hardware watchdog device to
 171         be present, as it is commonly the case in embedded and server
 172         systems. Not all hardware watchdogs allow configuration of the
 173         reboot timeout, in which case the closest available timeout is
 174         picked. <varname>ShutdownWatchdogSec=</varname> may be used to
 175         configure the hardware watchdog when the system is asked to
 176         reboot. It works as a safety net to ensure that the reboot
 177         takes place even if a clean reboot attempt times out. By
 178         default <varname>RuntimeWatchdogSec=</varname> defaults to 0
 179         (off), and <varname>ShutdownWatchdogSec=</varname> to 10min.
 180         These settings have no effect if a hardware watchdog is not
 181         available.</para></listitem>
 182       </varlistentry>
 183
 184       <varlistentry>
 185         <term><varname>WatchdogDevice=</varname></term>
 186
 187         <listitem><para>Configure the hardware watchdog device that the
 188         runtime and shutdown watchdog timers will open and use. Defaults
 189         to <filename>/dev/watchdog</filename>. This setting has no
 190         effect if a hardware watchdog is not available.</para></listitem>
 191       </varlistentry>
 192
 193       <varlistentry>
 194         <term><varname>CapabilityBoundingSet=</varname></term>
 195
 196         <listitem><para>Controls which capabilities to include in the
 197         capability bounding set for PID 1 and its children. See
 198         <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 199         for details. Takes a whitespace-separated list of capability
 200         names as read by
 201         <citerefentry project='mankier'><refentrytitle>cap_from_name</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 202         Capabilities listed will be included in the bounding set, all
 203         others are removed. If the list of capabilities is prefixed
 204         with ~, all but the listed capabilities will be included, the
 205         effect of the assignment inverted. Note that this option also
 206         affects the respective capabilities in the effective,
 207         permitted and inheritable capability sets. The capability
 208         bounding set may also be individually configured for units
 209         using the <varname>CapabilityBoundingSet=</varname> directive
 210         for units, but note that capabilities dropped for PID 1 cannot
 211         be regained in individual units, they are lost for
 212         good.</para></listitem>
 213       </varlistentry>
 214
 215       <varlistentry>
 216         <term><varname>SystemCallArchitectures=</varname></term>
 217
 218         <listitem><para>Takes a space-separated list of architecture
 219         identifiers. Selects from which architectures system calls may
 220         be invoked on this system. This may be used as an effective
 221         way to disable invocation of non-native binaries system-wide,
 222         for example to prohibit execution of 32-bit x86 binaries on
 223         64-bit x86-64 systems. This option operates system-wide, and
 224         acts similar to the
 225         <varname>SystemCallArchitectures=</varname> setting of unit
 226         files, see
 227         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 228         for details. This setting defaults to the empty list, in which
 229         case no filtering of system calls based on architecture is
 230         applied. Known architecture identifiers are
 231         <literal>x86</literal>, <literal>x86-64</literal>,
 232         <literal>x32</literal>, <literal>arm</literal> and the special
 233         identifier <literal>native</literal>. The latter implicitly
 234         maps to the native architecture of the system (or more
 235         specifically, the architecture the system manager was compiled
 236         for). Set this setting to <literal>native</literal> to
 237         prohibit execution of any non-native binaries. When a binary
 238         executes a system call of an architecture that is not listed
 239         in this setting, it will be immediately terminated with the
 240         SIGSYS signal.</para></listitem>
 241       </varlistentry>
 242
 243       <varlistentry>
 244         <term><varname>TimerSlackNSec=</varname></term>
 245
 246         <listitem><para>Sets the timer slack in nanoseconds for PID 1,
 247         which is inherited by all executed processes, unless
 248         overridden individually, for example with the
 249         <varname>TimerSlackNSec=</varname> setting in service units
 250         (for details see
 251         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>).
 252         The timer slack controls the accuracy of wake-ups triggered by
 253         system timers. See
 254         <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 255         for more information. Note that in contrast to most other time
 256         span definitions this parameter takes an integer value in
 257         nano-seconds if no unit is specified. The usual time units are
 258         understood too.</para></listitem>
 259       </varlistentry>
 260
 261       <varlistentry>
 262         <term><varname>DefaultTimerAccuracySec=</varname></term>
 263
 264         <listitem><para>Sets the default accuracy of timer units. This
 265         controls the global default for the
 266         <varname>AccuracySec=</varname> setting of timer units, see
 267         <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 268         for details. <varname>AccuracySec=</varname> set in individual
 269         units override the global default for the specific unit.
 270         Defaults to 1min. Note that the accuracy of timer units is
 271         also affected by the configured timer slack for PID 1, see
 272         <varname>TimerSlackNSec=</varname> above.</para></listitem>
 273       </varlistentry>
 274
 275       <varlistentry>
 276         <term><varname>DefaultTimeoutStartSec=</varname></term>
 277         <term><varname>DefaultTimeoutStopSec=</varname></term>
 278         <term><varname>DefaultRestartSec=</varname></term>
 279
 280         <listitem><para>Configures the default timeouts for starting
 281         and stopping of units, as well as the default time to sleep
 282         between automatic restarts of units, as configured per-unit in
 283         <varname>TimeoutStartSec=</varname>,
 284         <varname>TimeoutStopSec=</varname> and
 285         <varname>RestartSec=</varname> (for services, see
 286         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 287         for details on the per-unit settings). For non-service units,
 288         <varname>DefaultTimeoutStartSec=</varname> sets the default
 289         <varname>TimeoutSec=</varname>
 290         value. <varname>DefaultTimeoutStartSec=</varname> and
 291         <varname>DefaultTimeoutStopSec=</varname> default to
 292         90s. <varname>DefaultRestartSec=</varname> defaults to
 293         100ms.</para></listitem>
 294       </varlistentry>
 295
 296       <varlistentry>
 297         <term><varname>DefaultStartLimitIntervalSec=</varname></term>
 298         <term><varname>DefaultStartLimitBurst=</varname></term>
 299
 300         <listitem><para>Configure the default unit start rate
 301         limiting, as configured per-service by
 302         <varname>StartLimitIntervalSec=</varname> and
 303         <varname>StartLimitBurst=</varname>. See
 304         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 305         for details on the per-service settings.
 306         <varname>DefaultStartLimitIntervalSec=</varname> defaults to
 307         10s. <varname>DefaultStartLimitBurst=</varname> defaults to
 308         5.</para></listitem>
 309       </varlistentry>
 310
 311       <varlistentry>
 312         <term><varname>DefaultEnvironment=</varname></term>
 313
 314         <listitem><para>Sets manager environment variables passed to
 315         all executed processes. Takes a space-separated list of
 316         variable assignments. See
 317         <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 318         for details about environment variables.</para>
 319
 320         <para>Example:
 321
 322         <programlisting>DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"</programlisting>
 323
 324         Sets three variables
 325         <literal>VAR1</literal>,
 326         <literal>VAR2</literal>,
 327         <literal>VAR3</literal>.</para></listitem>
 328       </varlistentry>
 329
 330       <varlistentry>
 331         <term><varname>DefaultCPUAccounting=</varname></term>
 332         <term><varname>DefaultBlockIOAccounting=</varname></term>
 333         <term><varname>DefaultMemoryAccounting=</varname></term>
 334         <term><varname>DefaultTasksAccounting=</varname></term>
 335         <term><varname>DefaultIPAccounting=</varname></term>
 336
 337         <listitem><para>Configure the default resource accounting settings, as configured per-unit by
 338         <varname>CPUAccounting=</varname>, <varname>BlockIOAccounting=</varname>, <varname>MemoryAccounting=</varname>,
 339         <varname>TasksAccounting=</varname> and <varname>IPAccounting=</varname>. See
 340         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 341         for details on the per-unit settings. <varname>DefaultTasksAccounting=</varname> defaults to on, the other
 342         four settings to off.</para></listitem>
 343       </varlistentry>
 344
 345       <varlistentry>
 346         <term><varname>DefaultTasksMax=</varname></term>
 347
 348         <listitem><para>Configure the default value for the per-unit <varname>TasksMax=</varname> setting. See
 349         <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
 350         for details. This setting applies to all unit types that support resource control settings, with the exception
 351         of slice units. Defaults to 15%, which equals 4915 with the kernel's defaults on the host, but might be smaller
 352         in OS containers.</para></listitem>
 353       </varlistentry>
 354
 355       <varlistentry>
 356         <term><varname>DefaultLimitCPU=</varname></term>
 357         <term><varname>DefaultLimitFSIZE=</varname></term>
 358         <term><varname>DefaultLimitDATA=</varname></term>
 359         <term><varname>DefaultLimitSTACK=</varname></term>
 360         <term><varname>DefaultLimitCORE=</varname></term>
 361         <term><varname>DefaultLimitRSS=</varname></term>
 362         <term><varname>DefaultLimitNOFILE=</varname></term>
 363         <term><varname>DefaultLimitAS=</varname></term>
 364         <term><varname>DefaultLimitNPROC=</varname></term>
 365         <term><varname>DefaultLimitMEMLOCK=</varname></term>
 366         <term><varname>DefaultLimitLOCKS=</varname></term>
 367         <term><varname>DefaultLimitSIGPENDING=</varname></term>
 368         <term><varname>DefaultLimitMSGQUEUE=</varname></term>
 369         <term><varname>DefaultLimitNICE=</varname></term>
 370         <term><varname>DefaultLimitRTPRIO=</varname></term>
 371         <term><varname>DefaultLimitRTTIME=</varname></term>
 372
 373         <listitem><para>These settings control various default
 374         resource limits for units. See
 375         <citerefentry><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>
 376         for details. The resource limit is possible to specify in two formats,
 377         <option>value</option> to set soft and hard limits to the same value,
 378         or <option>soft:hard</option> to set both limits individually (e.g. DefaultLimitAS=4G:16G).
 379         Use the string <varname>infinity</varname> to
 380         configure no limit on a specific resource. The multiplicative
 381         suffixes K (=1024), M (=1024*1024) and so on for G, T, P and E
 382         may be used for resource limits measured in bytes
 383         (e.g. DefaultLimitAS=16G). For the limits referring to time values,
 384         the usual time units ms, s, min, h and so on may be used (see
 385         <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 386         for details). Note that if no time unit is specified for
 387         <varname>DefaultLimitCPU=</varname> the default unit of seconds is
 388         implied, while for <varname>DefaultLimitRTTIME=</varname> the default
 389         unit of microseconds is implied. Also, note that the effective
 390         granularity of the limits might influence their
 391         enforcement. For example, time limits specified for
 392         <varname>DefaultLimitCPU=</varname> will be rounded up implicitly to
 393         multiples of 1s. These  settings may be overridden in individual units
 394         using the corresponding LimitXXX= directives. Note that these resource
 395         limits are only defaults for units, they are not applied to PID 1
 396         itself.</para></listitem>
 397       </varlistentry>
 398     </variablelist>
 399   </refsect1>
 400
 401   <refsect1>
 402       <title>See Also</title>
 403       <para>
 404         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 405         <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 406         <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 407         <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 408         <citerefentry project='man-pages'><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
 409         <citerefentry project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
 410       </para>
 411   </refsect1>
 412
 413 </refentry>