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NAME | SYNOPSIS | DESCRIPTION | CONFIGURATION DIRECTORIES AND PRECEDENCE | OPTIONS | SPECIFIERS | HISTORY | SEE ALSO | NOTES | COLOPHON |
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SYSTEMD-SYSTEM.CONF(5) systemd-system.conf SYSTEMD-SYSTEM.CONF(5)
systemd-system.conf, system.conf.d, systemd-user.conf,
user.conf.d - System and session service manager configuration
files
/etc/systemd/system.conf, /run/systemd/system.conf,
/usr/lib/systemd/system.conf, /etc/systemd/system.conf.d/*.conf,
/run/systemd/system.conf.d/*.conf,
/usr/lib/systemd/system.conf.d/*.conf
~/.config/systemd/user.conf, /etc/systemd/user.conf,
/run/systemd/user.conf, /usr/lib/systemd/user.conf,
/etc/systemd/user.conf.d/*.conf, /run/systemd/user.conf.d/*.conf,
/usr/lib/systemd/user.conf.d/*.conf
When run as a system instance, systemd interprets the
configuration file system.conf and the files in system.conf.d
directories; when run as a user instance, it interprets the
configuration file user.conf (in order of priority, in the home
directory of the user and under /etc/systemd/, /run/systemd/, and
/usr/lib/systemd/) and the files in user.conf.d directories.
These configuration files contain a few settings controlling
basic manager operations.
See systemd.syntax(7) for a general description of the syntax.
The default configuration is set during compilation, so
configuration is only needed when it is necessary to deviate from
those defaults. The main configuration file is loaded from one of
the listed directories in order of priority, only the first file
found is used: /etc/systemd/, /run/systemd/,
/usr/local/lib/systemd/ [1], /usr/lib/systemd/. The vendor
version of the file contains commented out entries showing the
defaults as a guide to the administrator. Local overrides can
also be created by creating drop-ins, as described below. The
main configuration file can also be edited for this purpose (or a
copy in /etc/ if it's shipped under /usr/), however using
drop-ins for local configuration is recommended over
modifications to the main configuration file.
In addition to the main configuration file, drop-in configuration
snippets are read from /usr/lib/systemd/*.conf.d/,
/usr/local/lib/systemd/*.conf.d/, and /etc/systemd/*.conf.d/.
Those drop-ins have higher precedence and override the main
configuration file. Files in the *.conf.d/ configuration
subdirectories are sorted by their filename in lexicographic
order, regardless of in which of the subdirectories they reside.
When multiple files specify the same option, for options which
accept just a single value, the entry in the file sorted last
takes precedence, and for options which accept a list of values,
entries are collected as they occur in the sorted files.
When packages need to customize the configuration, they can
install drop-ins under /usr/. Files in /etc/ are reserved for the
local administrator, who may use this logic to override the
configuration files installed by vendor packages. Drop-ins have
to be used to override package drop-ins, since the main
configuration file has lower precedence. It is recommended to
prefix all filenames in those subdirectories with a two-digit
number and a dash, to simplify the ordering. This also defines a
concept of drop-in priorities to allow OS vendors to ship
drop-ins within a specific range lower than the range used by
users. This should lower the risk of package drop-ins overriding
accidentally drop-ins defined by users. It is recommended to use
the range 10-40 for drop-ins in /usr/ and the range 60-90 for
drop-ins in /etc/ and /run/, to make sure that local and
transient drop-ins take priority over drop-ins shipped by the OS
vendor.
To disable a configuration file supplied by the vendor, the
recommended way is to place a symlink to /dev/null in the
configuration directory in /etc/, with the same filename as the
vendor configuration file.
All options are configured in the [Manager] section:
LogColor=, LogLevel=, LogLocation=, LogTarget=, LogTime=,
DumpCore=yes, CrashChangeVT=no, CrashShell=no,
CrashAction=freeze, ShowStatus=yes,
DefaultStandardOutput=journal, DefaultStandardError=inherit
Configures various parameters of basic manager operation.
These options may be overridden by the respective process and
kernel command line arguments. See systemd(1) for details.
Added in version 198.
CtrlAltDelBurstAction=
Defines what action will be performed if user presses
Ctrl-Alt-Delete more than 7 times in 2s. Can be set to
"reboot-force", "poweroff-force", "reboot-immediate",
"poweroff-immediate" or disabled with "none". Defaults to
"reboot-force".
Added in version 232.
CPUAffinity=
Configures the CPU affinity for the service manager as well
as the default CPU affinity for all forked off processes.
Takes a list of CPU indices or ranges separated by either
whitespace or commas. CPU ranges are specified by the lower
and upper CPU indices separated by a dash. This option may be
specified more than once, in which case the specified CPU
affinity masks are merged. If the empty string is assigned,
the mask is reset, all assignments prior to this will have no
effect. Individual services may override the CPU affinity for
their processes with the CPUAffinity= setting in unit files,
see systemd.exec(5).
Added in version 198.
NUMAPolicy=
Configures the NUMA memory policy for the service manager and
the default NUMA memory policy for all forked off processes.
Individual services may override the default policy with the
NUMAPolicy= setting in unit files, see systemd.exec(5).
Added in version 243.
NUMAMask=
Configures the NUMA node mask that will be associated with
the selected NUMA policy. Note that default and local NUMA
policies don't require explicit NUMA node mask and value of
the option can be empty. Similarly to NUMAPolicy=, value can
be overridden by individual services in unit files, see
systemd.exec(5).
Added in version 243.
RuntimeWatchdogSec=, RebootWatchdogSec=, KExecWatchdogSec=
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"), or the special
strings "off" or "default". If set to "off" (alternatively:
"0") the watchdog logic is disabled: no watchdog device is
opened, configured, or pinged. If set to the special string
"default" the watchdog is opened and pinged in regular
intervals, but the timeout is not changed from the default.
If set to any other time value the watchdog timeout is
configured to the specified value (or a value close to it,
depending on hardware capabilities).
If RuntimeWatchdogSec= is set to a non-zero value, the
watchdog hardware (/dev/watchdog0 or the path specified with
WatchdogDevice= or the kernel option
systemd.watchdog-device=) 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 all possible
reboot timeout values, in which case the closest available
timeout is picked.
RebootWatchdogSec= 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. Note that the
RebootWatchdogSec= timeout applies only to the second phase
of the reboot, i.e. after all regular services are already
terminated, and after the system and service manager process
(PID 1) got replaced by the systemd-shutdown binary, see
system bootup(7) for details. During the first phase of the
shutdown operation the system and service manager remains
running and hence RuntimeWatchdogSec= is still honoured. In
order to define a timeout on this first phase of system
shutdown, configure JobTimeoutSec= and JobTimeoutAction= in
the [Unit] section of the shutdown.target unit. By default
RuntimeWatchdogSec= defaults to 0 (off), and
RebootWatchdogSec= to 10min.
KExecWatchdogSec= may be used to additionally enable the
watchdog when kexec is being executed rather than when
rebooting. Note that if the kernel does not reset the
watchdog on kexec (depending on the specific hardware and/or
driver), in this case the watchdog might not get disabled
after kexec succeeds and thus the system might get rebooted,
unless RuntimeWatchdogSec= is also enabled at the same time.
For this reason it is recommended to enable KExecWatchdogSec=
only if RuntimeWatchdogSec= is also enabled.
These settings have no effect if a hardware watchdog is not
available.
Added in version 198.
RuntimeWatchdogPreSec=
Configure the hardware watchdog device pre-timeout value.
Takes a timeout value in seconds (or in other time units
similar to RuntimeWatchdogSec=). A watchdog pre-timeout is a
notification generated by the watchdog before the watchdog
reset might occur in the event the watchdog has not been
serviced. This notification is handled by the kernel and can
be configured to take an action (i.e. generate a kernel
panic) using RuntimeWatchdogPreGovernor=. Not all watchdog
hardware or drivers support generating a pre-timeout and
depending on the state of the system, the kernel may be
unable to take the configured action before the watchdog
reboot. The watchdog will be configured to generate the
pre-timeout event at the amount of time specified by
RuntimeWatchdogPreSec= before the runtime watchdog timeout
(set by RuntimeWatchdogSec=). For example, if the we have
RuntimeWatchdogSec=30 and RuntimeWatchdogPreSec=10, then the
pre-timeout event will occur if the watchdog has not pinged
for 20s (10s before the watchdog would fire). By default,
RuntimeWatchdogPreSec= defaults to 0 (off). The value set for
RuntimeWatchdogPreSec= must be smaller than the timeout value
for RuntimeWatchdogSec=. This setting has no effect if a
hardware watchdog is not available or the hardware watchdog
does not support a pre-timeout and will be ignored by the
kernel if the setting is greater than the actual watchdog
timeout.
Added in version 251.
RuntimeWatchdogPreGovernor=
Configure the action taken by the hardware watchdog device
when the pre-timeout expires. The default action for the
pre-timeout event depends on the kernel configuration, but it
is usually to log a kernel message. For a list of valid
actions available for a given watchdog device, check the
content of the
/sys/class/watchdog/watchdogX/pretimeout_available_governors
file. Typically, available governor types are noop and panic.
Availability, names and functionality might vary depending on
the specific device driver in use. If the
pretimeout_available_governors sysfs file is empty, the
governor might be built as a kernel module and might need to
be manually loaded (e.g. pretimeout_noop.ko), or the
watchdog device might not support pre-timeouts.
Added in version 251.
WatchdogDevice=
Configure the hardware watchdog device that the runtime and
shutdown watchdog timers will open and use. Defaults to
/dev/watchdog0. This setting has no effect if a hardware
watchdog is not available.
Added in version 236.
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.
Added in version 198.
NoNewPrivileges=
Takes a boolean argument. If true, ensures that PID 1 and all
its children can never gain new privileges through execve(2)
(e.g. via setuid or setgid bits, or filesystem capabilities).
Defaults to false. General purpose distributions commonly
rely on executables with setuid or setgid bits and will thus
not function properly with this option enabled. Individual
units cannot disable this option. Also see No New Privileges
Flag[2].
Added in version 239.
ProtectSystem=
Takes a boolean argument or the string "auto". If set to true
this will remount /usr/ read-only. If set to "auto" (the
default) and running in an initrd equivalent to true,
otherwise false. This implements a restricted subset of the
per-unit setting of the same name, see systemd.exec(5) for
details: currently, the "full" or "struct" values are not
supported.
Added in version 256.
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.
Added in version 209.
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.
Added in version 198.
StatusUnitFormat=
Takes name, description or combined as the value. If name,
the system manager will use unit names in status messages
(e.g. "systemd-journald.service"), instead of the longer and
more informative descriptions set with Description= (e.g.
"Journal Logging Service"). If combined, the system manager
will use both unit names and descriptions in status messages
(e.g. "systemd-journald.service - Journal Logging Service").
See systemd.unit(5) for details about unit names and
Description=.
Added in version 243.
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.
Added in version 212.
DefaultTimeoutStartSec=, DefaultTimeoutStopSec=,
DefaultTimeoutAbortSec=, DefaultRestartSec=
Configures the default timeouts for starting, stopping and
aborting of units, as well as the default time to sleep
between automatic restarts of units, as configured per-unit
in TimeoutStartSec=, TimeoutStopSec=, TimeoutAbortSec= 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.
DefaultTimeoutStartSec= and DefaultTimeoutStopSec= default to
90 s in the system manager and 90 s in the user manager.
DefaultTimeoutAbortSec= is not set by default so that all
units fall back to TimeoutStopSec=. DefaultRestartSec=
defaults to 100 ms.
Added in version 209.
DefaultDeviceTimeoutSec=
Configures the default timeout for waiting for devices. It
can be changed per device via the x-systemd.device-timeout=
option in /etc/fstab and /etc/crypttab (see systemd.mount(5),
crypttab(5)). Defaults to 90 s in the system manager and 90 s
in the user manager.
Added in version 252.
DefaultStartLimitIntervalSec=, DefaultStartLimitBurst=
Configure the default unit start rate limiting, as configured
per-service by StartLimitIntervalSec= and StartLimitBurst=.
See systemd.service(5) for details on the per-service
settings. DefaultStartLimitIntervalSec= defaults to 10s.
DefaultStartLimitBurst= defaults to 5.
Added in version 209.
DefaultEnvironment=
Configures environment variables passed to all executed
processes. Takes a space-separated list of variable
assignments. See environ(7) for details about environment
variables.
Simple "%"-specifier expansion is supported, see below for a
list of supported specifiers.
Example:
DefaultEnvironment="VAR1=word1 word2" VAR2=word3 "VAR3=word 5 6"
Sets three variables "VAR1", "VAR2", "VAR3".
Added in version 205.
ManagerEnvironment=
Takes the same arguments as DefaultEnvironment=, see above.
Sets environment variables just for the manager process
itself. In contrast to user managers, these variables are not
inherited by processes spawned by the system manager, use
DefaultEnvironment= for that. Note that these variables are
merged into the existing environment block. In particular, in
case of the system manager, this includes variables set by
the kernel based on the kernel command line.
Setting environment variables for the manager process may be
useful to modify its behaviour. See Known Environment
Variables[3] for a descriptions of some variables understood
by systemd.
Simple "%"-specifier expansion is supported, see below for a
list of supported specifiers.
Added in version 248.
DefaultCPUAccounting=, DefaultMemoryAccounting=,
DefaultTasksAccounting=, DefaultIOAccounting=,
DefaultIPAccounting=
Configure the default resource accounting settings, as
configured per-unit by CPUAccounting=, MemoryAccounting=,
TasksAccounting=, IOAccounting= and IPAccounting=. See
systemd.resource-control(5) for details on the per-unit
settings.
DefaultCPUAccounting= defaults to yes when running on kernel
≥4.15, and no on older versions. DefaultMemoryAccounting=
defaults to yes. DefaultTasksAccounting= defaults to yes.
The other settings default to no.
Added in version 211.
DefaultTasksMax=
Configure the default value for the per-unit TasksMax=
setting. See systemd.resource-control(5) for details. This
setting applies to all unit types that support resource
control settings, with the exception of slice units. Defaults
to 15% of the minimum of kernel.pid_max=, kernel.threads-max=
and root cgroup pids.max. Kernel has a default value for
kernel.pid_max= and an algorithm of counting in case of more
than 32 cores. For example, with the default kernel.pid_max=,
DefaultTasksMax= defaults to 4915, but might be greater in
other systems or smaller in OS containers.
Added in version 228.
DefaultLimitCPU=, DefaultLimitFSIZE=, DefaultLimitDATA=,
DefaultLimitSTACK=, DefaultLimitCORE=, DefaultLimitRSS=,
DefaultLimitNOFILE=, DefaultLimitAS=, DefaultLimitNPROC=,
DefaultLimitMEMLOCK=, DefaultLimitLOCKS=,
DefaultLimitSIGPENDING=, DefaultLimitMSGQUEUE=,
DefaultLimitNICE=, DefaultLimitRTPRIO=, DefaultLimitRTTIME=
These settings control various default resource limits for
processes executed by units. See setrlimit(2) for details.
These settings may be overridden in individual units using
the corresponding LimitXXX= directives and they accept the
same parameter syntax, see systemd.exec(5) for details. Note
that these resource limits are only defaults for units, they
are not applied to the service manager process (i.e. PID 1)
itself.
Most of these settings are unset, which means the resource
limits are inherited from the kernel or, if invoked in a
container, from the container manager. However, the following
have defaults:
• DefaultLimitNOFILE= defaults to 1024:524288.
• DefaultLimitMEMLOCK= defaults to 8M.
• DefaultLimitCORE= does not have a default but it is worth
mentioning that RLIMIT_CORE is set to "infinity" by PID 1
which is inherited by its children.
Note that the service manager internally in PID 1 bumps
RLIMIT_NOFILE and RLIMIT_MEMLOCK to higher values, however
the limit is reverted to the mentioned defaults for all child
processes forked off.
Added in version 198.
DefaultOOMPolicy=
Configure the default policy for reacting to processes being
killed by the Linux Out-Of-Memory (OOM) killer or
systemd-oomd. This may be used to pick a global default for
the per-unit OOMPolicy= setting. See systemd.service(5) for
details. Note that this default is not used for services that
have Delegate= turned on.
Added in version 243.
DefaultOOMScoreAdjust=
Configures the default OOM score adjustments of processes run
by the service manager. This defaults to unset (meaning the
forked off processes inherit the service manager's OOM score
adjustment value), except if the service manager is run for
an unprivileged user, in which case this defaults to the
service manager's OOM adjustment value plus 100 (this makes
service processes slightly more likely to be killed under
memory pressure than the manager itself). This may be used to
pick a global default for the per-unit OOMScoreAdjust=
setting. See systemd.exec(5) for details. Note that this
setting has no effect on the OOM score adjustment value of
the service manager process itself, it retains the original
value set during its invocation.
Added in version 250.
DefaultSmackProcessLabel=
Takes a SMACK64 security label as the argument. The process
executed by a unit will be started under this label if
SmackProcessLabel= is not set in the unit. See
systemd.exec(5) for the details.
If the value is "/", only labels specified with
SmackProcessLabel= are assigned and the compile-time default
is ignored.
Added in version 252.
ReloadLimitIntervalSec=, ReloadLimitBurst=
Rate limiting for daemon-reload and (since v256)
daemon-reexec requests. The setting applies to both
operations, but the rate limits are tracked separately.
Defaults to unset, and any number of operations can be
requested at any time. ReloadLimitIntervalSec= takes a value
in seconds to configure the rate limit window, and
ReloadLimitBurst= takes a positive integer to configure the
maximum allowed number of operations within the configured
time window.
Added in version 253.
DefaultMemoryPressureWatch=, DefaultMemoryPressureThresholdSec=
Configures the default settings for the per-unit
MemoryPressureWatch= and MemoryPressureThresholdSec=
settings. See systemd.resource-control(5) for details.
Defaults to "auto" and "200ms", respectively. This also sets
the memory pressure monitoring threshold for the service
manager itself.
Added in version 254.
Specifiers may be used in the DefaultEnvironment= and
ManagerEnvironment= settings. The following expansions are
understood:
Table 1. Specifiers available
┌───────────┬──────────────────┬────────────────────────┐
│ Specifier │ Meaning │ Details │
├───────────┼──────────────────┼────────────────────────┤
│ "%a" │ Architecture │ A short string │
│ │ │ identifying the │
│ │ │ architecture of │
│ │ │ the local system. │
│ │ │ A string such as │
│ │ │ x86, x86-64 or │
│ │ │ arm64. See the │
│ │ │ architectures │
│ │ │ defined for │
│ │ │ ConditionArchitecture= │
│ │ │ in systemd.unit(5) │
│ │ │ for a full list. │
├───────────┼──────────────────┼────────────────────────┤
│ "%A" │ Operating system │ The operating system │
│ │ image version │ image version │
│ │ │ identifier of the │
│ │ │ running system, as │
│ │ │ read from the │
│ │ │ IMAGE_VERSION= field │
│ │ │ of /etc/os-release. If │
│ │ │ not set, resolves to │
│ │ │ an empty string. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%b" │ Boot ID │ The boot ID of the │
│ │ │ running system, │
│ │ │ formatted as string. │
│ │ │ See random(4) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%B" │ Operating system │ The operating system │
│ │ build ID │ build identifier of │
│ │ │ the running system, as │
│ │ │ read from the │
│ │ │ BUILD_ID= field of │
│ │ │ /etc/os-release. If │
│ │ │ not set, resolves to │
│ │ │ an empty string. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%H" │ Host name │ The hostname of the │
│ │ │ running system. │
├───────────┼──────────────────┼────────────────────────┤
│ "%l" │ Short host name │ The hostname of the │
│ │ │ running system, │
│ │ │ truncated at the first │
│ │ │ dot to remove any │
│ │ │ domain component. │
├───────────┼──────────────────┼────────────────────────┤
│ "%m" │ Machine ID │ The machine ID of the │
│ │ │ running system, │
│ │ │ formatted as string. │
│ │ │ See machine-id(5) for │
│ │ │ more information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%M" │ Operating system │ The operating system │
│ │ image identifier │ image identifier of │
│ │ │ the running system, as │
│ │ │ read from the │
│ │ │ IMAGE_ID= field of │
│ │ │ /etc/os-release. If │
│ │ │ not set, resolves to │
│ │ │ an empty string. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%o" │ Operating system │ The operating system │
│ │ ID │ identifier of the │
│ │ │ running system, as │
│ │ │ read from the ID= │
│ │ │ field of │
│ │ │ /etc/os-release. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%v" │ Kernel release │ Identical to uname -r │
│ │ │ output. │
├───────────┼──────────────────┼────────────────────────┤
│ "%w" │ Operating system │ The operating system │
│ │ version ID │ version identifier of │
│ │ │ the running system, as │
│ │ │ read from the │
│ │ │ VERSION_ID= field of │
│ │ │ /etc/os-release. If │
│ │ │ not set, resolves to │
│ │ │ an empty string. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%W" │ Operating system │ The operating system │
│ │ variant ID │ variant identifier of │
│ │ │ the running system, as │
│ │ │ read from the │
│ │ │ VARIANT_ID= field of │
│ │ │ /etc/os-release. If │
│ │ │ not set, resolves to │
│ │ │ an empty string. See │
│ │ │ os-release(5) for more │
│ │ │ information. │
├───────────┼──────────────────┼────────────────────────┤
│ "%T" │ Directory for │ This is either /tmp or │
│ │ temporary files │ the path "$TMPDIR", │
│ │ │ "$TEMP" or "$TMP" are │
│ │ │ set to. (Note that the │
│ │ │ directory may be │
│ │ │ specified without a │
│ │ │ trailing slash.) │
├───────────┼──────────────────┼────────────────────────┤
│ "%V" │ Directory for │ This is either │
│ │ larger and │ /var/tmp or the path │
│ │ persistent │ "$TMPDIR", "$TEMP" or │
│ │ temporary files │ "$TMP" are set to. │
│ │ │ (Note that the │
│ │ │ directory may be │
│ │ │ specified without a │
│ │ │ trailing slash.) │
├───────────┼──────────────────┼────────────────────────┤
│ "%h" │ User home │ This is the home │
│ │ directory │ directory of the user │
│ │ │ running the service │
│ │ │ manager instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%u" │ Username │ This is the username │
│ │ │ of the user running │
│ │ │ the service manager │
│ │ │ instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%U" │ User id │ This is the user id of │
│ │ │ the user running the │
│ │ │ service manager │
│ │ │ instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%g" │ Primary group │ This is the primary │
│ │ │ group of the user │
│ │ │ running the service │
│ │ │ manager instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%G" │ Primary group id │ This is the primary │
│ │ │ group id of the user │
│ │ │ running the service │
│ │ │ manager instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%s" │ User shell │ This is the shell of │
│ │ │ the user running the │
│ │ │ service manager │
│ │ │ instance. │
├───────────┼──────────────────┼────────────────────────┤
│ "%%" │ Single percent │ Use "%%" in place of │
│ │ sign │ "%" to specify a │
│ │ │ single percent sign. │
└───────────┴──────────────────┴────────────────────────┘
systemd 252
Option DefaultBlockIOAccounting= was deprecated. Please
switch to the unified cgroup hierarchy.
Added in version 252.
systemd(1), systemd.directives(7), systemd.exec(5),
systemd.service(5), environ(7), capabilities(7)
1. 💣💥🧨💥💥💣 Please note that those configuration files must
be available at all times. If /usr/local/ is a separate
partition, it may not be available during early boot, and
must not be used for configuration.
2. No New Privileges Flag
https://docs.kernel.org/userspace-api/no_new_privs.html
3. Known Environment Variables
https://systemd.io/ENVIRONMENT
This page is part of the systemd (systemd system and service
manager) project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have
a bug report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
systemd 257~devel SYSTEMD-SYSTEM.CONF(5)
Pages that refer to this page: run0(1), systemctl(1), systemd(1), journald.conf(5), logind.conf(5), systemd.exec(5), systemd.mount(5), systemd.resource-control(5), systemd.scope(5), systemd.service(5), systemd.socket(5), systemd.swap(5), systemd.timer(5), systemd.unit(5), kernel-command-line(7), systemd.directives(7), systemd.index(7), systemd.syntax(7), systemd-oomd.service(8)
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