systemd-system.conf, systemd-user.conf — System and session service manager configuration file
/etc/systemd/system.conf
/etc/systemd/user.conf
When run as system instance systemd reads the
configuration file system.conf
,
otherwise user.conf
. These
configuration files contain a few settings controlling
basic manager operations.
All options are configured in the
"[Manager]
" section:
LogLevel=
, LogTarget=
, LogColor=
, LogLocation=
, DumpCore=yes
, CrashShell=no
, ShowStatus=yes
, CrashChVT=1
, DefaultStandardOutput=journal
, DefaultStandardError=inherit
¶Configures various parameters of basic manager operation. These options may be overridden by the respective command line arguments. See systemd(1) for details about these command line arguments.
CPUAffinity=
¶Configures the initial CPU affinity for the init process. Takes a space-separated list of CPU indices.
JoinControllers=cpu,cpuacct net_cls,netprio
¶Configures controllers that shall be mounted in a single hierarchy. By default, systemd will mount all controllers which are enabled in the kernel in individual hierarchies, with the exception of those listed in this setting. Takes a space-separated list of comma-separated controller names, in order to allow multiple joined hierarchies. Defaults to 'cpu,cpuacct'. Pass an empty string to ensure that systemd mounts all controllers in separate hierarchies.
Note that this option is only applied once, at very early boot. If you use an initial RAM disk (initrd) that uses systemd, it might hence be necessary to rebuild the initrd if this option is changed, and make sure the new configuration file is included in it. Otherwise, the initrd might mount the controller hierarchies in a different configuration than intended, and the main system cannot remount them anymore.
RuntimeWatchdogSec=
, ShutdownWatchdogSec=
¶Configure the hardware
watchdog at runtime and at
reboot. Takes a timeout value in
seconds (or in other time units if
suffixed with "ms
",
"min
",
"h
",
"d
",
"w
"). If
RuntimeWatchdogSec=
is set to a non-zero value, the
watchdog hardware
(/dev/watchdog
)
will be programmed to automatically
reboot the system if it is not
contacted within the specified timeout
interval. The system manager will
ensure to contact it at least once in
half the specified timeout
interval. This feature requires a
hardware watchdog device to be
present, as it is commonly the case in
embedded and server systems. Not all
hardware watchdogs allow configuration
of the reboot timeout, in which case
the closest available timeout is
picked. ShutdownWatchdogSec=
may be used to configure the hardware
watchdog when the system is asked to
reboot. It works as a safety net to
ensure that the reboot takes place
even if a clean reboot attempt times
out. By default
RuntimeWatchdogSec=
defaults to 0 (off), and
ShutdownWatchdogSec=
to 10min. These settings have no
effect if a hardware watchdog is not
available.
CapabilityBoundingSet=
¶Controls which
capabilities to include in the
capability bounding set for PID 1 and
its children. See
capabilities(7)
for details. Takes a whitespace-separated
list of capability names as read by
cap_from_name(3).
Capabilities listed will be included
in the bounding set, all others are
removed. If the list of capabilities
is prefixed with ~, all but the listed
capabilities will be included, the
effect of the assignment
inverted. Note that this option also
affects the respective capabilities in
the effective, permitted and
inheritable capability sets. The
capability bounding set may also be
individually configured for units
using the
CapabilityBoundingSet=
directive for units, but note that
capabilities dropped for PID 1 cannot
be regained in individual units, they
are lost for good.
SystemCallArchitectures=
¶Takes a
space-separated list of architecture
identifiers. Selects from which
architectures system calls may be
invoked on this system. This may be
used as an effective way to disable
invocation of non-native binaries
system-wide, for example to prohibit
execution of 32-bit x86 binaries on
64-bit x86-64 systems. This option
operates system-wide, and acts
similar to the
SystemCallArchitectures=
setting of unit files, see
systemd.exec(5)
for details. This setting defaults to
the empty list, in which case no
filtering of system calls based on
architecture is applied. Known
architecture identifiers are
"x86
",
"x86-64
",
"x32
",
"arm
" and the special
identifier
"native
". The latter
implicitly maps to the native
architecture of the system (or more
specifically, the architecture the
system manager was compiled for). Set
this setting to
"native
" to prohibit
execution of any non-native
binaries. When a binary executes a
system call of an architecture that is
not listed in this setting, it will be
immediately terminated with the SIGSYS
signal.
TimerSlackNSec=
¶Sets the timer slack
in nanoseconds for PID 1, which is
inherited by all executed processes,
unless overridden individually, for
example with the
TimerSlackNSec=
setting in service units (for details
see
systemd.exec(5)). The
timer slack controls the accuracy of
wake-ups triggered by system
timers. See
prctl(2)
for more information. Note that in
contrast to most other time span
definitions this parameter takes an
integer value in nano-seconds if no
unit is specified. The usual time
units are understood
too.
DefaultTimerAccuracySec=
¶Sets the default
accuracy of timer units. This controls
the global default for the
AccuracySec=
setting of timer units, see
systemd.timer(5)
for
details. AccuracySec=
set in individual units override the
global default for the specific
unit. Defaults to 1min. Note that the
accuracy of timer units is also
affected by the configured timer slack
for PID 1, see
TimerSlackNSec=
above.
DefaultTimeoutStartSec=
, DefaultTimeoutStopSec=
, DefaultRestartSec=
¶Configures the default
timeouts for starting and stopping of
units, as well as the default time to
sleep between automatic restarts of
units, as configured per-unit in
TimeoutStartSec=
,
TimeoutStopSec=
and
RestartSec=
(for
services, see
systemd.service(5)
for details on the per-unit
settings). For non-service units,
DefaultTimeoutStartSec=
sets the default
TimeoutSec=
value.
DefaultStartLimitInterval=
, DefaultStartLimitBurst=
¶Configure the default
unit start rate limiting, as
configured per-service by
StartLimitInterval=
and
StartLimitBurst=
. See
systemd.service(5)
for details on the per-service
settings.
DefaultEnvironment=
¶Sets manager environment variables passed to all executed processes. Takes a space-separated list of variable assignments. See environ(7) for details about environment variables.
Example:
DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"
Sets three variables
"VAR1
",
"VAR2
",
"VAR3
".
DefaultCPUAccounting=
, DefaultBlockIOAccounting=
, DefaultMemoryAccounting=
¶Configure the default
resource accounting settings, as
configured per-unit by
CPUAccounting=
,
BlockIOAccounting=
and
MemoryAccounting=
. See
systemd.resource-control(5)
for details on the per-unit
settings.
DefaultLimitCPU=
, DefaultLimitFSIZE=
, DefaultLimitDATA=
, DefaultLimitSTACK=
, DefaultLimitCORE=
, DefaultLimitRSS=
, DefaultLimitNOFILE=
, DefaultLimitAS=
, DefaultLimitNPROC=
, DefaultLimitMEMLOCK=
, DefaultLimitLOCKS=
, DefaultLimitSIGPENDING=
, DefaultLimitMSGQUEUE=
, DefaultLimitNICE=
, DefaultLimitRTPRIO=
, DefaultLimitRTTIME=
¶These settings control
various default resource limits for
units. See
setrlimit(2)
for details. Use the string
infinity
to
configure no limit on a specific
resource. These settings may be
overridden in individual units
using the corresponding LimitXXX=
directives. Note that these resource
limits are only defaults for units,
they are not applied to PID 1
itself.