Ubuntu Manpage: Config::Model::models::Systemd::Section::Service - Configuration class Systemd::Section::Service

Provided by: libconfig-model-systemd-perl_0.236.1-1_all

NAME

       Config::Model::models::Systemd::Section::Service - Configuration class Systemd::Section::Service

DESCRIPTION

Configuration classes used by Config::Model

A unit configuration file whose name ends in .service encodes information about a process controlled and
supervised by systemd.

This man page lists the configuration options specific to this unit type. See systemd.unit(5) for the
common options of all unit configuration files. The common configuration items are configured in the
generic "[Unit]" and "[Install]" sections. The service specific configuration options are configured in
the "[Service]" section.

Additional options are listed in systemd.exec(5), which define the execution environment the commands are
executed in, and in systemd.kill(5), which define the way the processes of the service are terminated,
and in systemd.resource-control(5), which configure resource control settings for the processes of the
service.

If a service is requested under a certain name but no unit configuration file is found, systemd looks for
a SysV init script by the same name (with the .service suffix removed) and dynamically creates a service
unit from that script. This is useful for compatibility with SysV. Note that this compatibility is quite
comprehensive but not 100%. For details about the incompatibilities, see the Incompatibilities with SysV
document. This configuration class was generated from systemd documentation. by parse-man.pl
<https://github.com/dod38fr/config-model-systemd/contrib/parse-man.pl>

Elements

CPUAccounting
Turn on CPU usage accounting for this unit. Takes a boolean argument. Note that turning on CPU accounting
for one unit will also implicitly turn it on for all units contained in the same slice and for all its
parent slices and the units contained therein. The system default for this setting may be controlled with
"DefaultCPUAccounting" in systemd-system.conf(5). Optional. Type boolean.

CPUWeight
Assign the specified CPU time weight to the processes executed, if the unified control group hierarchy is
used on the system. These options take an integer value and control the "cpu.weight" control group
attribute. The allowed range is 1 to 10000. Defaults to 100. For details about this control group
attribute, see cgroup-v2.txt and sched-design-CFS.txt. The available CPU time is split up among all
units within one slice relative to their CPU time weight.

While "StartupCPUWeight" only applies to the startup phase of the system, "CPUWeight" applies to normal
runtime of the system, and if the former is not set also to the startup phase. Using "StartupCPUWeight"
allows prioritizing specific services at boot-up differently than during normal runtime.

Implies "CPUAccounting=true".

These settings replace "CPUShares" and "StartupCPUShares". Optional. Type integer.

upstream_default value :
100

StartupCPUWeight
Assign the specified CPU time weight to the processes executed, if the unified control group hierarchy is
used on the system. These options take an integer value and control the "cpu.weight" control group
attribute. The allowed range is 1 to 10000. Defaults to 100. For details about this control group
attribute, see cgroup-v2.txt and sched-design-CFS.txt. The available CPU time is split up among all
units within one slice relative to their CPU time weight.

Implies "CPUAccounting=true".

These settings replace "CPUShares" and "StartupCPUShares". Optional. Type integer.

upstream_default value :
100

CPUQuota
Assign the specified CPU time quota to the processes executed. Takes a percentage value, suffixed with
"%". The percentage specifies how much CPU time the unit shall get at maximum, relative to the total CPU
time available on one CPU. Use values > 100% for allotting CPU time on more than one CPU. This controls
the "cpu.max" attribute on the unified control group hierarchy and "cpu.cfs_quota_us" on legacy. For
details about these control group attributes, see cgroup-v2.txt and sched-design-CFS.txt.

Example: "CPUQuota=20%" ensures that the executed processes will never get more than 20% CPU time on one
CPU.

Implies "CPUAccounting=true". Optional. Type uniline.

MemoryAccounting
Turn on process and kernel memory accounting for this unit. Takes a boolean argument. Note that turning
on memory accounting for one unit will also implicitly turn it on for all units contained in the same
slice and for all its parent slices and the units contained therein. The system default for this setting
may be controlled with "DefaultMemoryAccounting" in systemd-system.conf(5). Optional. Type boolean.

MemoryLow
Specify the best-effort memory usage protection of the executed processes in this unit. If the memory
usages of this unit and all its ancestors are below their low boundaries, this unit's memory won't be
reclaimed as long as memory can be reclaimed from unprotected units.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is
parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively.
Alternatively, a percentage value may be specified, which is taken relative to the installed physical
memory on the system. This controls the "memory.low" control group attribute. For details about this
control group attribute, see cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables "MemoryLimit".
Optional. Type uniline.

MemoryHigh
Specify the high limit on memory usage of the executed processes in this unit. Memory usage may go above
the limit if unavoidable, but the processes are heavily slowed down and memory is taken away aggressively
in such cases. This is the main mechanism to control memory usage of a unit.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is
parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively.
Alternatively, a percentage value may be specified, which is taken relative to the installed physical
memory on the system. If assigned the special value "infinity", no memory limit is applied. This controls
the "memory.high" control group attribute. For details about this control group attribute, see
cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables "MemoryLimit".
Optional. Type uniline.

MemoryMax
Specify the absolute limit on memory usage of the executed processes in this unit. If memory usage cannot
be contained under the limit, out-of-memory killer is invoked inside the unit. It is recommended to use
"MemoryHigh" as the main control mechanism and use "MemoryMax" as the last line of defense.

Takes a memory size in bytes. If the value is suffixed with K, M, G or T, the specified memory size is
parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively.
Alternatively, a percentage value may be specified, which is taken relative to the installed physical
memory on the system. If assigned the special value "infinity", no memory limit is applied. This controls
the "memory.max" control group attribute. For details about this control group attribute, see
cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting replaces "MemoryLimit". Optional. Type uniline.

MemorySwapMax
Specify the absolute limit on swap usage of the executed processes in this unit.

Takes a swap size in bytes. If the value is suffixed with K, M, G or T, the specified swap size is parsed
as Kilobytes, Megabytes, Gigabytes, or Terabytes (with the base 1024), respectively. If assigned the
special value "infinity", no swap limit is applied. This controls the "memory.swap.max" control group
attribute. For details about this control group attribute, see cgroup-v2.txt.

Implies "MemoryAccounting=true".

This setting is supported only if the unified control group hierarchy is used and disables "MemoryLimit".
Optional. Type uniline.

TasksAccounting
Turn on task accounting for this unit. Takes a boolean argument. If enabled, the system manager will keep
track of the number of tasks in the unit. The number of tasks accounted this way includes both kernel
threads and userspace processes, with each thread counting individually. Note that turning on tasks
accounting for one unit will also implicitly turn it on for all units contained in the same slice and for
all its parent slices and the units contained therein. The system default for this setting may be
controlled with "DefaultTasksAccounting" in systemd-system.conf(5). Optional. Type boolean.

TasksMax
Specify the maximum number of tasks that may be created in the unit. This ensures that the number of
tasks accounted for the unit (see above) stays below a specific limit. This either takes an absolute
number of tasks or a percentage value that is taken relative to the configured maximum number of tasks on
the system. If assigned the special value "infinity", no tasks limit is applied. This controls the
"pids.max" control group attribute. For details about this control group attribute, see pids.txt.

Implies "TasksAccounting=true". The system default for this setting may be controlled with
"DefaultTasksMax" in systemd-system.conf(5). Optional. Type uniline.

IOAccounting
Turn on Block I/O accounting for this unit, if the unified control group hierarchy is used on the system.
Takes a boolean argument. Note that turning on block I/O accounting for one unit will also implicitly
turn it on for all units contained in the same slice and all for its parent slices and the units
contained therein. The system default for this setting may be controlled with "DefaultIOAccounting" in
systemd-system.conf(5).

This setting replaces "BlockIOAccounting" and disables settings prefixed with "BlockIO" or
"StartupBlockIO". Optional. Type boolean.

IOWeight
Set the default overall block I/O weight for the executed processes, if the unified control group
hierarchy is used on the system. Takes a single weight value (between 1 and 10000) to set the default
block I/O weight. This controls the "io.weight" control group attribute, which defaults to 100. For
details about this control group attribute, see cgroup-v2.txt. The available I/O bandwidth is split up
among all units within one slice relative to their block I/O weight.

While "StartupIOWeight" only applies to the startup phase of the system, "IOWeight" applies to the later
runtime of the system, and if the former is not set also to the startup phase. This allows prioritizing
specific services at boot-up differently than during runtime.

Implies "IOAccounting=true".

These settings replace "BlockIOWeight" and "StartupBlockIOWeight" and disable settings prefixed with
"BlockIO" or "StartupBlockIO". Optional. Type uniline.

StartupIOWeight
Set the default overall block I/O weight for the executed processes, if the unified control group
hierarchy is used on the system. Takes a single weight value (between 1 and 10000) to set the default
block I/O weight. This controls the "io.weight" control group attribute, which defaults to 100. For
details about this control group attribute, see cgroup-v2.txt. The available I/O bandwidth is split up
among all units within one slice relative to their block I/O weight.

Implies "IOAccounting=true".

These settings replace "BlockIOWeight" and "StartupBlockIOWeight" and disable settings prefixed with
"BlockIO" or "StartupBlockIO". Optional. Type uniline.

IODeviceWeight
Set the per-device overall block I/O weight for the executed processes, if the unified control group
hierarchy is used on the system. Takes a space-separated pair of a file path and a weight value to
specify the device specific weight value, between 1 and 10000. (Example: "/dev/sda 1000"). The file path
may be specified as path to a block device node or as any other file, in which case the backing block
device of the file system of the file is determined. This controls the "io.weight" control group
attribute, which defaults to 100. Use this option multiple times to set weights for multiple devices. For
details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

This setting replaces "BlockIODeviceWeight" and disables settings prefixed with "BlockIO" or
"StartupBlockIO". Optional. Type uniline.

IOReadBandwidthMax
Set the per-device overall block I/O bandwidth maximum limit for the executed processes, if the unified
control group hierarchy is used on the system. This limit is not work-conserving and the executed
processes are not allowed to use more even if the device has idle capacity. Takes a space-separated pair
of a file path and a bandwidth value (in bytes per second) to specify the device specific bandwidth. The
file path may be a path to a block device node, or as any other file in which case the backing block
device of the file system of the file is used. If the bandwidth is suffixed with K, M, G, or T, the
specified bandwidth is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes, respectively, to the base
of 1000. (Example: "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "io.max"
control group attributes. Use this option multiple times to set bandwidth limits for multiple devices.
For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings replace "BlockIOReadBandwidth" and "BlockIOWriteBandwidth" and disable settings prefixed
with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOWriteBandwidthMax
Set the per-device overall block I/O bandwidth maximum limit for the executed processes, if the unified
control group hierarchy is used on the system. This limit is not work-conserving and the executed
processes are not allowed to use more even if the device has idle capacity. Takes a space-separated pair
of a file path and a bandwidth value (in bytes per second) to specify the device specific bandwidth. The
file path may be a path to a block device node, or as any other file in which case the backing block
device of the file system of the file is used. If the bandwidth is suffixed with K, M, G, or T, the
specified bandwidth is parsed as Kilobytes, Megabytes, Gigabytes, or Terabytes, respectively, to the base
of 1000. (Example: "/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "io.max"
control group attributes. Use this option multiple times to set bandwidth limits for multiple devices.
For details about this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings replace "BlockIOReadBandwidth" and "BlockIOWriteBandwidth" and disable settings prefixed
with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOReadIOPSMax
Set the per-device overall block I/O IOs-Per-Second maximum limit for the executed processes, if the
unified control group hierarchy is used on the system. This limit is not work-conserving and the executed
processes are not allowed to use more even if the device has idle capacity. Takes a space-separated pair
of a file path and an IOPS value to specify the device specific IOPS. The file path may be a path to a
block device node, or as any other file in which case the backing block device of the file system of the
file is used. If the IOPS is suffixed with K, M, G, or T, the specified IOPS is parsed as KiloIOPS,
MegaIOPS, GigaIOPS, or TeraIOPS, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 1K"). This controls the "io.max" control group
attributes. Use this option multiple times to set IOPS limits for multiple devices. For details about
this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings are supported only if the unified control group hierarchy is used and disable settings
prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IOWriteIOPSMax
Set the per-device overall block I/O IOs-Per-Second maximum limit for the executed processes, if the
unified control group hierarchy is used on the system. This limit is not work-conserving and the executed
processes are not allowed to use more even if the device has idle capacity. Takes a space-separated pair
of a file path and an IOPS value to specify the device specific IOPS. The file path may be a path to a
block device node, or as any other file in which case the backing block device of the file system of the
file is used. If the IOPS is suffixed with K, M, G, or T, the specified IOPS is parsed as KiloIOPS,
MegaIOPS, GigaIOPS, or TeraIOPS, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 1K"). This controls the "io.max" control group
attributes. Use this option multiple times to set IOPS limits for multiple devices. For details about
this control group attribute, see cgroup-v2.txt.

Implies "IOAccounting=true".

These settings are supported only if the unified control group hierarchy is used and disable settings
prefixed with "BlockIO" or "StartupBlockIO". Optional. Type uniline.

IPAccounting
Takes a boolean argument. If true, turns on IPv4 and IPv6 network traffic accounting for packets sent or
received by the unit. When this option is turned on, all IPv4 and IPv6 sockets created by any process of
the unit are accounted for. When this option is used in socket units, it applies to all IPv4 and IPv6
sockets associated with it (including both listening and connection sockets where this applies). Note
that for socket-activated services, this configuration setting and the accounting data of the service
unit and the socket unit are kept separate, and displayed separately. No propagation of the setting and
the collected statistics is done, in either direction. Moreover, any traffic sent or received on any of
the socket unit's sockets is accounted to the socket unit X and never to the service unit it might have
activated, even if the socket is used by it. Note that IP accounting is currently not supported for slice
units, and enabling this option for them has no effect. The system default for this setting may be
controlled with "DefaultIPAccounting" in systemd-system.conf(5). Optional. Type boolean.

IPAddressAllow
Turn on address range network traffic filtering for packets sent and received over AF_INET and AF_INET6
sockets. Both directives take a space separated list of IPv4 or IPv6 addresses, each optionally suffixed
with an address prefix length (separated by a "/" character). If the latter is omitted, the address is
considered a host address, i.e. the prefix covers the whole address (32 for IPv4, 128 for IPv6).

The access lists configured with this option are applied to all sockets created by processes of this unit
(or in the case of socket units, associated with it). The lists are implicitly combined with any lists
configured for any of the parent slice units this unit might be a member of. By default all access lists
are empty. When configured the lists are enforced as follows:

In order to implement a whitelisting IP firewall, it is recommended to use a "IPAddressDeny""any" setting
on an upper-level slice unit (such as the root slice -.slice or the slice containing all system services
system.slice X see systemd.special(7) for details on these slice units), plus individual per-service
"IPAddressAllow" lines permitting network access to relevant services, and only them.

Note that for socket-activated services, the IP access list configured on the socket unit applies to all
sockets associated with it directly, but not to any sockets created by the ultimately activated services
for it. Conversely, the IP access list configured for the service is not applied to any sockets passed
into the service via socket activation. Thus, it is usually a good idea, to replicate the IP access lists
on both the socket and the service unit, however it often makes sense to maintain one list more open and
the other one more restricted, depending on the usecase.

If these settings are used multiple times in the same unit the specified lists are combined. If an empty
string is assigned to these settings the specific access list is reset and all previous settings undone.

In place of explicit IPv4 or IPv6 address and prefix length specifications a small set of symbolic names
may be used. The following names are defined:

Note that these settings might not be supported on some systems (for example if eBPF control group
support is not enabled in the underlying kernel or container manager). These settings will have no effect
in that case. If compatibility with such systems is desired it is hence recommended to not exclusively
rely on them for IP security. Optional. Type uniline.

IPAddressDeny
Turn on address range network traffic filtering for packets sent and received over AF_INET and AF_INET6
sockets. Both directives take a space separated list of IPv4 or IPv6 addresses, each optionally suffixed
with an address prefix length (separated by a "/" character). If the latter is omitted, the address is
considered a host address, i.e. the prefix covers the whole address (32 for IPv4, 128 for IPv6).

In place of explicit IPv4 or IPv6 address and prefix length specifications a small set of symbolic names
may be used. The following names are defined:

DeviceAllow
Control access to specific device nodes by the executed processes. Takes two space-separated strings: a
device node specifier followed by a combination of "r", "w", "m" to control reading, writing, or creation
of the specific device node(s) by the unit (mknod), respectively. This controls the "devices.allow" and
"devices.deny" control group attributes. For details about these control group attributes, see
devices.txt.

The device node specifier is either a path to a device node in the file system, starting with /dev/, or a
string starting with either "char-" or "block-" followed by a device group name, as listed in
/proc/devices. The latter is useful to whitelist all current and future devices belonging to a specific
device group at once. The device group is matched according to filename globbing rules, you may hence use
the "*" and "?" wildcards. Examples: /dev/sda5 is a path to a device node, referring to an ATA or SCSI
block device. "char-pts" and "char-alsa" are specifiers for all pseudo TTYs and all ALSA sound devices,
respectively. "char-cpu/*" is a specifier matching all CPU related device groups. Optional. Type list of
uniline.

DevicePolicy
Control the policy for allowing device access: Optional. Type enum. choice: 'auto', 'closed', 'strict'.

Slice
The name of the slice unit to place the unit in. Defaults to system.slice for all non-instantiated units
of all unit types (except for slice units themselves see below). Instance units are by default placed in
a subslice of system.slice that is named after the template name.

This option may be used to arrange systemd units in a hierarchy of slices each of which might have
resource settings applied.

For units of type slice, the only accepted value for this setting is the parent slice. Since the name of
a slice unit implies the parent slice, it is hence redundant to ever set this parameter directly for
slice units.

Special care should be taken when relying on the default slice assignment in templated service units that
have "DefaultDependencies=no" set, see systemd.service(5), section "Default Dependencies" for details.
Optional. Type uniline.

Delegate
Turns on delegation of further resource control partitioning to processes of the unit. Units where this
is enabled may create and manage their own private subhierarchy of control groups below the control group
of the unit itself. For unprivileged services (i.e. those using the "User" setting) the unit's control
group will be made accessible to the relevant user. When enabled the service manager will refrain from
manipulating control groups or moving processes below the unit's control group, so that a clear concept
of ownership is established: the control group tree above the unit's control group (i.e. towards the root
control group) is owned and managed by the service manager of the host, while the control group tree
below the unit's control group is owned and managed by the unit itself. Takes either a boolean argument
or a list of control group controller names. If true, delegation is turned on, and all supported
controllers are enabled for the unit, making them available to the unit's processes for management. If
false, delegation is turned off entirely (and no additional controllers are enabled). If set to a list of
controllers, delegation is turned on, and the specified controllers are enabled for the unit. Note that
additional controllers than the ones specified might be made available as well, depending on
configuration of the containing slice unit or other units contained in it. Note that assigning the empty
string will enable delegation, but reset the list of controllers, all assignments prior to this will have
no effect. Defaults to false.

Note that controller delegation to less privileged code is only safe on the unified control group
hierarchy. Accordingly, access to the specified controllers will not be granted to unprivileged services
on the legacy hierarchy, even when requested.

The following controller names may be specified: "cpu", "cpuacct", "io", "blkio", "memory", "devices",
"pids". Not all of these controllers are available on all kernels however, and some are specific to the
unified hierarchy while others are specific to the legacy hierarchy. Also note that the kernel might
support further controllers, which aren't covered here yet as delegation is either not supported at all
for them or not defined cleanly. Optional. Type uniline.

CPUShares
Assign the specified CPU time share weight to the processes executed. These options take an integer value
and control the "cpu.shares" control group attribute. The allowed range is 2 to 262144. Defaults to 1024.
For details about this control group attribute, see sched-design-CFS.txt. The available CPU time is
split up among all units within one slice relative to their CPU time share weight.

While "StartupCPUShares" only applies to the startup phase of the system, "CPUShares" applies to normal
runtime of the system, and if the former is not set also to the startup phase. Using "StartupCPUShares"
allows prioritizing specific services at boot-up differently than during normal runtime.

Implies "CPUAccounting=true".

These settings are deprecated. Use "CPUWeight" and "StartupCPUWeight" instead. Optional. Type integer.

upstream_default value :
1024

StartupCPUShares
Assign the specified CPU time share weight to the processes executed. These options take an integer value
and control the "cpu.shares" control group attribute. The allowed range is 2 to 262144. Defaults to 1024.
For details about this control group attribute, see sched-design-CFS.txt. The available CPU time is
split up among all units within one slice relative to their CPU time share weight.

Implies "CPUAccounting=true".

These settings are deprecated. Use "CPUWeight" and "StartupCPUWeight" instead. Optional. Type integer.

upstream_default value :
1024

MemoryLimit
Specify the limit on maximum memory usage of the executed processes. The limit specifies how much process
and kernel memory can be used by tasks in this unit. Takes a memory size in bytes. If the value is
suffixed with K, M, G or T, the specified memory size is parsed as Kilobytes, Megabytes, Gigabytes, or
Terabytes (with the base 1024), respectively. Alternatively, a percentage value may be specified, which
is taken relative to the installed physical memory on the system. If assigned the special value
"infinity", no memory limit is applied. This controls the "memory.limit_in_bytes" control group
attribute. For details about this control group attribute, see memory.txt.

Implies "MemoryAccounting=true".

This setting is deprecated. Use "MemoryMax" instead. Optional. Type uniline.

BlockIOAccounting
Turn on Block I/O accounting for this unit, if the legacy control group hierarchy is used on the system.
Takes a boolean argument. Note that turning on block I/O accounting for one unit will also implicitly
turn it on for all units contained in the same slice and all for its parent slices and the units
contained therein. The system default for this setting may be controlled with "DefaultBlockIOAccounting"
in systemd-system.conf(5).

This setting is deprecated. Use "IOAccounting" instead. Optional. Type boolean.

BlockIOWeight
Set the default overall block I/O weight for the executed processes, if the legacy control group
hierarchy is used on the system. Takes a single weight value (between 10 and 1000) to set the default
block I/O weight. This controls the "blkio.weight" control group attribute, which defaults to 500. For
details about this control group attribute, see blkio-controller.txt. The available I/O bandwidth is
split up among all units within one slice relative to their block I/O weight.

While "StartupBlockIOWeight" only applies to the startup phase of the system, "BlockIOWeight" applies to
the later runtime of the system, and if the former is not set also to the startup phase. This allows
prioritizing specific services at boot-up differently than during runtime.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOWeight" and "StartupIOWeight" instead. Optional. Type uniline.

StartupBlockIOWeight
Set the default overall block I/O weight for the executed processes, if the legacy control group
hierarchy is used on the system. Takes a single weight value (between 10 and 1000) to set the default
block I/O weight. This controls the "blkio.weight" control group attribute, which defaults to 500. For
details about this control group attribute, see blkio-controller.txt. The available I/O bandwidth is
split up among all units within one slice relative to their block I/O weight.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOWeight" and "StartupIOWeight" instead. Optional. Type uniline.

BlockIODeviceWeight
Set the per-device overall block I/O weight for the executed processes, if the legacy control group
hierarchy is used on the system. Takes a space-separated pair of a file path and a weight value to
specify the device specific weight value, between 10 and 1000. (Example: "/dev/sda 500"). The file path
may be specified as path to a block device node or as any other file, in which case the backing block
device of the file system of the file is determined. This controls the "blkio.weight_device" control
group attribute, which defaults to 1000. Use this option multiple times to set weights for multiple
devices. For details about this control group attribute, see blkio-controller.txt.

Implies "BlockIOAccounting=true".

This setting is deprecated. Use "IODeviceWeight" instead. Optional. Type uniline.

BlockIOReadBandwidth
Set the per-device overall block I/O bandwidth limit for the executed processes, if the legacy control
group hierarchy is used on the system. Takes a space-separated pair of a file path and a bandwidth value
(in bytes per second) to specify the device specific bandwidth. The file path may be a path to a block
device node, or as any other file in which case the backing block device of the file system of the file
is used. If the bandwidth is suffixed with K, M, G, or T, the specified bandwidth is parsed as Kilobytes,
Megabytes, Gigabytes, or Terabytes, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "blkio.throttle.read_bps_device"
and "blkio.throttle.write_bps_device" control group attributes. Use this option multiple times to set
bandwidth limits for multiple devices. For details about these control group attributes, see
blkio-controller.txt.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOReadBandwidthMax" and "IOWriteBandwidthMax" instead. Optional.
Type uniline.

BlockIOWriteBandwidth
Set the per-device overall block I/O bandwidth limit for the executed processes, if the legacy control
group hierarchy is used on the system. Takes a space-separated pair of a file path and a bandwidth value
(in bytes per second) to specify the device specific bandwidth. The file path may be a path to a block
device node, or as any other file in which case the backing block device of the file system of the file
is used. If the bandwidth is suffixed with K, M, G, or T, the specified bandwidth is parsed as Kilobytes,
Megabytes, Gigabytes, or Terabytes, respectively, to the base of 1000. (Example:
"/dev/disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0 5M"). This controls the "blkio.throttle.read_bps_device"
and "blkio.throttle.write_bps_device" control group attributes. Use this option multiple times to set
bandwidth limits for multiple devices. For details about these control group attributes, see
blkio-controller.txt.

Implies "BlockIOAccounting=true".

These settings are deprecated. Use "IOReadBandwidthMax" and "IOWriteBandwidthMax" instead. Optional.
Type uniline.

WorkingDirectory
Takes a directory path relative to the service's root directory specified by "RootDirectory", or the
special value "~". Sets the working directory for executed processes. If set to "~", the home directory
of the user specified in "User" is used. If not set, defaults to the root directory when systemd is
running as a system instance and the respective user's home directory if run as user. If the setting is
prefixed with the "-" character, a missing working directory is not considered fatal. If
"RootDirectory"/"RootImage" is not set, then "WorkingDirectory" is relative to the root of the system
running the service manager. Note that setting this parameter might result in additional dependencies to
be added to the unit (see above). Optional. Type uniline.

RootDirectory
Takes a directory path relative to the host's root directory (i.e. the root of the system running the
service manager). Sets the root directory for executed processes, with the chroot(2) system call. If this
is used, it must be ensured that the process binary and all its auxiliary files are available in the
chroot() jail. Note that setting this parameter might result in additional dependencies to be added to
the unit (see above).

The "MountAPIVFS" and "PrivateUsers" settings are particularly useful in conjunction with
"RootDirectory". For details, see below. Optional. Type uniline.

RootImage
Takes a path to a block device node or regular file as argument. This call is similar to "RootDirectory"
however mounts a file system hierarchy from a block device node or loopback file instead of a directory.
The device node or file system image file needs to contain a file system without a partition table, or a
file system within an MBR/MS-DOS or GPT partition table with only a single Linux-compatible partition, or
a set of file systems within a GPT partition table that follows the Discoverable Partitions
Specification. Optional. Type uniline.

MountAPIVFS
Takes a boolean argument. If on, a private mount namespace for the unit's processes is created and the
API file systems /proc, /sys, and /dev are mounted inside of it, unless they are already mounted. Note
that this option has no effect unless used in conjunction with "RootDirectory"/"RootImage" as these three
mounts are generally mounted in the host anyway, and unless the root directory is changed, the private
mount namespace will be a 1:1 copy of the host's, and include these three mounts. Note that the /dev file
system of the host is bind mounted if this option is used without "PrivateDevices". To run the service
with a private, minimal version of /dev/, combine this option with "PrivateDevices". Optional. Type
boolean.

BindPaths
Configures unit-specific bind mounts. A bind mount makes a particular file or directory available at an
additional place in the unit's view of the file system. Any bind mounts created with this option are
specific to the unit, and are not visible in the host's mount table. This option expects a whitespace
separated list of bind mount definitions. Each definition consists of a colon-separated triple of source
path, destination path and option string, where the latter two are optional. If only a source path is
specified the source and destination is taken to be the same. The option string may be either "rbind" or
"norbind" for configuring a recursive or non-recursive bind mount. If the destination path is omitted,
the option string must be omitted too.

"BindPaths" creates regular writable bind mounts (unless the source file system mount is already marked
read-only), while "BindReadOnlyPaths" creates read-only bind mounts. These settings may be used more than
once, each usage appends to the unit's list of bind mounts. If the empty string is assigned to either of
these two options the entire list of bind mounts defined prior to this is reset. Note that in this case
both read-only and regular bind mounts are reset, regardless which of the two settings is used.

This option is particularly useful when "RootDirectory"/"RootImage" is used. In this case the source path
refers to a path on the host file system, while the destination path refers to a path below the root
directory of the unit. Optional. Type list of uniline.

BindReadOnlyPaths
Configures unit-specific bind mounts. A bind mount makes a particular file or directory available at an
additional place in the unit's view of the file system. Any bind mounts created with this option are
specific to the unit, and are not visible in the host's mount table. This option expects a whitespace
separated list of bind mount definitions. Each definition consists of a colon-separated triple of source
path, destination path and option string, where the latter two are optional. If only a source path is
specified the source and destination is taken to be the same. The option string may be either "rbind" or
"norbind" for configuring a recursive or non-recursive bind mount. If the destination path is omitted,
the option string must be omitted too.

User
Set the UNIX user or group that the processes are executed as, respectively. Takes a single user or group
name, or a numeric ID as argument. For system services (services run by the system service manager, i.e.
managed by PID 1) and for user services of the root user (services managed by root's instance of systemd
--user), the default is "root", but "User" may be used to specify a different user. For user services of
any other user, switching user identity is not permitted, hence the only valid setting is the same user
the user's service manager is running as. If no group is set, the default group of the user is used. This
setting does not affect commands whose command line is prefixed with "+".

Note that restrictions on the user/group name syntax are enforced: the specified name must consist only
of the characters a-z, A-Z, 0-9, "_" and "-", except for the first character which must be one of a-z,
A-Z or "_" (i.e. numbers and "-" are not permitted as first character). The user/group name must have at
least one character, and at most 31. These restrictions are enforced in order to avoid ambiguities and to
ensure user/group names and unit files remain portable among Linux systems.

When used in conjunction with "DynamicUser" the user/group name specified is dynamically allocated at the
time the service is started, and released at the time the service is stopped X unless it is already
allocated statically (see below). If "DynamicUser" is not used the specified user and group must have
been created statically in the user database no later than the moment the service is started, for example
using the sysusers.d(5) facility, which is applied at boot or package install time. Optional. Type
uniline.

Group
Set the UNIX user or group that the processes are executed as, respectively. Takes a single user or group
name, or a numeric ID as argument. For system services (services run by the system service manager, i.e.
managed by PID 1) and for user services of the root user (services managed by root's instance of systemd
--user), the default is "root", but "User" may be used to specify a different user. For user services of
any other user, switching user identity is not permitted, hence the only valid setting is the same user
the user's service manager is running as. If no group is set, the default group of the user is used. This
setting does not affect commands whose command line is prefixed with "+".

DynamicUser
Takes a boolean parameter. If set, a UNIX user and group pair is allocated dynamically when the unit is
started, and released as soon as it is stopped. The user and group will not be added to /etc/passwd or
/etc/group, but are managed transiently during runtime. The nss-systemd(8) glibc NSS module provides
integration of these dynamic users/groups into the system's user and group databases. The user and group
name to use may be configured via "User" and "Group" (see above). If these options are not used and
dynamic user/group allocation is enabled for a unit, the name of the dynamic user/group is implicitly
derived from the unit name. If the unit name without the type suffix qualifies as valid user name it is
used directly, otherwise a name incorporating a hash of it is used. If a statically allocated user or
group of the configured name already exists, it is used and no dynamic user/group is allocated. Note that
if "User" is specified and the static group with the name exists, then it is required that the static
user with the name already exists. Similarly, if "Group" is specified and the static user with the name
exists, then it is required that the static group with the name already exists. Dynamic users/groups are
allocated from the UID/GID range 61184X65519. It is recommended to avoid this range for regular system or
login users. At any point in time each UID/GID from this range is only assigned to zero or one
dynamically allocated users/groups in use. However, UID/GIDs are recycled after a unit is terminated.
Care should be taken that any processes running as part of a unit for which dynamic users/groups are
enabled do not leave files or directories owned by these users/groups around, as a different unit might
get the same UID/GID assigned later on, and thus gain access to these files or directories. If
"DynamicUser" is enabled, "RemoveIPC", "PrivateTmp" are implied. This ensures that the lifetime of IPC
objects and temporary files created by the executed processes is bound to the runtime of the service, and
hence the lifetime of the dynamic user/group. Since /tmp and /var/tmp are usually the only world-writable
directories on a system this ensures that a unit making use of dynamic user/group allocation cannot leave
files around after unit termination. Moreover "ProtectSystem=strict" and "ProtectHome=read-only" are
implied, thus prohibiting the service to write to arbitrary file system locations. In order to allow the
service to write to certain directories, they have to be whitelisted using "ReadWritePaths", but care
must be taken so that UID/GID recycling doesn't create security issues involving files created by the
service. Use "RuntimeDirectory" (see below) in order to assign a writable runtime directory to a service,
owned by the dynamic user/group and removed automatically when the unit is terminated. Use
"StateDirectory", "CacheDirectory" and "LogsDirectory" in order to assign a set of writable directories
for specific purposes to the service in a way that they are protected from vulnerabilities due to UID
reuse (see below). Defaults to off. Optional. Type boolean.

SupplementaryGroups
Sets the supplementary Unix groups the processes are executed as. This takes a space-separated list of
group names or IDs. This option may be specified more than once, in which case all listed groups are set
as supplementary groups. When the empty string is assigned, the list of supplementary groups is reset,
and all assignments prior to this one will have no effect. In any way, this option does not override, but
extends the list of supplementary groups configured in the system group database for the user. This does
not affect commands prefixed with "+". Optional. Type list of uniline.

PAMName
Sets the PAM service name to set up a session as. If set, the executed process will be registered as a
PAM session under the specified service name. This is only useful in conjunction with the "User" setting,
and is otherwise ignored. If not set, no PAM session will be opened for the executed processes. See
pam(8) for details.

Note that for each unit making use of this option a PAM session handler process will be maintained as
part of the unit and stays around as long as the unit is active, to ensure that appropriate actions can
be taken when the unit and hence the PAM session terminates. This process is named "(sd-pam)" and is an
immediate child process of the unit's main process.

Note that when this option is used for a unit it is very likely (depending on PAM configuration) that the
main unit process will be migrated to its own session scope unit when it is activated. This process will
hence be associated with two units: the unit it was originally started from (and for which "PAMName" was
configured), and the session scope unit. Any child processes of that process will however be associated
with the session scope unit only. This has implications when used in combination with
"NotifyAccess""all", as these child processes will not be able to affect changes in the original unit
through notification messages. These messages will be considered belonging to the session scope unit and
not the original unit. It is hence not recommended to use "PAMName" in combination with
"NotifyAccess""all". Optional. Type uniline.

CapabilityBoundingSet
Controls which capabilities to include in the capability bounding set for the executed process. See
capabilities(7) for details. Takes a whitespace-separated list of capability names, e.g. "CAP_SYS_ADMIN",
"CAP_DAC_OVERRIDE", "CAP_SYS_PTRACE". 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. If this option is
not used, the capability bounding set is not modified on process execution, hence no limits on the
capabilities of the process are enforced. This option may appear more than once, in which case the
bounding sets are merged by "AND", or by "OR" if the lines are prefixed with "~" (see below). If the
empty string is assigned to this option, the bounding set is reset to the empty capability set, and all
prior settings have no effect. If set to "~" (without any further argument), the bounding set is reset
to the full set of available capabilities, also undoing any previous settings. This does not affect
commands prefixed with "+".

Example: if a unit has the following,

CapabilityBoundingSet=CAP_A CAP_B
CapabilityBoundingSet=CAP_B CAP_C

then "CAP_A", "CAP_B", and "CAP_C" are set. If the second line is prefixed with "~", e.g.,

CapabilityBoundingSet=CAP_A CAP_B
CapabilityBoundingSet=~CAP_B CAP_C

then, only "CAP_A" is set. Optional. Type uniline.

AmbientCapabilities
Controls which capabilities to include in the ambient capability set for the executed process. Takes a
whitespace-separated list of capability names, e.g. "CAP_SYS_ADMIN", "CAP_DAC_OVERRIDE",
"CAP_SYS_PTRACE". This option may appear more than once in which case the ambient capability sets are
merged (see the above examples in "CapabilityBoundingSet"). If the list of capabilities is prefixed with
"~", all but the listed capabilities will be included, the effect of the assignment inverted. If the
empty string is assigned to this option, the ambient capability set is reset to the empty capability set,
and all prior settings have no effect. If set to "~" (without any further argument), the ambient
capability set is reset to the full set of available capabilities, also undoing any previous settings.
Note that adding capabilities to ambient capability set adds them to the process's inherited capability
set.

Ambient capability sets are useful if you want to execute a process as a non-privileged user but still
want to give it some capabilities. Note that in this case option "keep-caps" is automatically added to
"SecureBits" to retain the capabilities over the user change. "AmbientCapabilities" does not affect
commands prefixed with "+". Optional. Type uniline.

NoNewPrivileges
Takes a boolean argument. If true, ensures that the service process and all its children can never gain
new privileges through execve() (e.g. via setuid or setgid bits, or filesystem capabilities). This is the
simplest and most effective way to ensure that a process and its children can never elevate privileges
again. Defaults to false, but certain settings force "NoNewPrivileges=yes", ignoring the value of this
setting. This is the case when "SystemCallFilter", "SystemCallArchitectures", "RestrictAddressFamilies",
"RestrictNamespaces", "PrivateDevices", "ProtectKernelTunables", "ProtectKernelModules",
"MemoryDenyWriteExecute", or "RestrictRealtime" are specified. Also see No New Privileges Flag.
Optional. Type boolean.

SecureBits
Controls the secure bits set for the executed process. Takes a space-separated combination of options
from the following list: "keep-caps", "keep-caps-locked", "no-setuid-fixup", "no-setuid-fixup-locked",
"noroot", and "noroot-locked". This option may appear more than once, in which case the secure bits are
ORed. If the empty string is assigned to this option, the bits are reset to 0. This does not affect
commands prefixed with "+". See capabilities(7) for details. Optional. Type uniline.

SELinuxContext
Set the SELinux security context of the executed process. If set, this will override the automated domain
transition. However, the policy still needs to authorize the transition. This directive is ignored if
SELinux is disabled. If prefixed by "-", all errors will be ignored. This does not affect commands
prefixed with "+". See setexeccon(3) for details. Optional. Type uniline.

AppArmorProfile
Takes a profile name as argument. The process executed by the unit will switch to this profile when
started. Profiles must already be loaded in the kernel, or the unit will fail. This result in a non
operation if AppArmor is not enabled. If prefixed by "-", all errors will be ignored. This does not
affect commands prefixed with "+". Optional. Type uniline.

SmackProcessLabel
Takes a "SMACK64" security label as argument. The process executed by the unit will be started under this
label and SMACK will decide whether the process is allowed to run or not, based on it. The process will
continue to run under the label specified here unless the executable has its own "SMACK64EXEC" label, in
which case the process will transition to run under that label. When not specified, the label that
systemd is running under is used. This directive is ignored if SMACK is disabled.

The value may be prefixed by "-", in which case all errors will be ignored. An empty value may be
specified to unset previous assignments. This does not affect commands prefixed with "+". Optional. Type
uniline.

LimitCPU
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

Note that most process resource limits configured with these options are per-process, and processes may
fork in order to acquire a new set of resources that are accounted independently of the original process,
and may thus escape limits set. Also note that "LimitRSS" is not implemented on Linux, and setting it has
no effect. Often it is advisable to prefer the resource controls listed in systemd.resource-control(5)
over these per-process limits, as they apply to services as a whole, may be altered dynamically at
runtime, and are generally more expressive. For example, "MemoryLimit" is a more powerful (and working)
replacement for "LimitRSS".

For system units these resource limits may be chosen freely. For user units however (i.e. units run by a
per-user instance of systemd(1)), these limits are bound by (possibly more restrictive) per-user limits
enforced by the OS.

Resource limits not configured explicitly for a unit default to the value configured in the various
"DefaultLimitCPU", "DefaultLimitFSIZE", X options available in systemd-system.conf(5), and X if not
configured there X the kernel or per-user defaults, as defined by the OS (the latter only for user
services, see above). Optional. Type uniline.

LimitFSIZE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitDATA
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitSTACK
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitCORE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitRSS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitNOFILE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitAS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitNPROC
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitMEMLOCK
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitLOCKS
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitSIGPENDING
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitMSGQUEUE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitNICE
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitRTPRIO
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

LimitRTTIME
Set soft and hard limits on various resources for executed processes. See setrlimit(2) for details on the
resource limit concept. Resource limits may be specified in two formats: either as single value to set a
specific soft and hard limit to the same value, or as colon-separated pair "soft:hard" to set both limits
individually (e.g. "LimitAS=4G:16G"). Use the string "infinity" to configure no limit on a specific
resource. The multiplicative suffixes K, M, G, T, P and E (to the base 1024) may be used for resource
limits measured in bytes (e.g. LimitAS=16G). For the limits referring to time values, the usual time
units ms, s, min, h and so on may be used (see systemd.time(7) for details). Note that if no time unit is
specified for "LimitCPU" the default unit of seconds is implied, while for "LimitRTTIME" the default unit
of microseconds is implied. Also, note that the effective granularity of the limits might influence their
enforcement. For example, time limits specified for "LimitCPU" will be rounded up implicitly to multiples
of 1s. For "LimitNICE" the value may be specified in two syntaxes: if prefixed with "+" or "-", the value
is understood as regular Linux nice value in the range -20..19. If not prefixed like this the value is
understood as raw resource limit parameter in the range 0..40 (with 0 being equivalent to 1).

UMask
Controls the file mode creation mask. Takes an access mode in octal notation. See umask(2) for details.
Defaults to 0022. Optional. Type uniline.

KeyringMode
Controls how the kernel session keyring is set up for the service (see session-keyring(7) for details on
the session keyring). Takes one of "inherit", "private", "shared". If set to "inherit" no special keyring
setup is done, and the kernel's default behaviour is applied. If "private" is used a new session keyring
is allocated when a service process is invoked, and it is not linked up with any user keyring. This is
the recommended setting for system services, as this ensures that multiple services running under the
same system user ID (in particular the root user) do not share their key material among each other. If
"shared" is used a new session keyring is allocated as for "private", but the user keyring of the user
configured with "User" is linked into it, so that keys assigned to the user may be requested by the
unit's processes. In this modes multiple units running processes under the same user ID may share key
material. Unless "inherit" is selected the unique invocation ID for the unit (see below) is added as a
protected key by the name "invocation_id" to the newly created session keyring. Defaults to "private" for
the system service manager and to "inherit" for the user service manager. Optional. Type enum. choice:
'inherit', 'private', 'shared'.

OOMScoreAdjust
Sets the adjustment level for the Out-Of-Memory killer for executed processes. Takes an integer between
-1000 (to disable OOM killing for this process) and 1000 (to make killing of this process under memory
pressure very likely). See proc.txt for details. Optional. Type integer.

TimerSlackNSec
Sets the timer slack in nanoseconds for the executed processes. The timer slack controls the accuracy of
wake-ups triggered by 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. Optional. Type uniline.

Personality
Controls which kernel architecture uname(2) shall report, when invoked by unit processes. Takes one of
the architecture identifiers "x86", "x86-64", "ppc", "ppc-le", "ppc64", "ppc64-le", "s390" or "s390x".
Which personality architectures are supported depends on the system architecture. Usually the 64bit
versions of the various system architectures support their immediate 32bit personality architecture
counterpart, but no others. For example, "x86-64" systems support the "x86-64" and "x86" personalities
but no others. The personality feature is useful when running 32-bit services on a 64-bit host system. If
not specified, the personality is left unmodified and thus reflects the personality of the host system's
kernel. Optional. Type enum. choice: 'x86', 'x86-64', 'ppc', 'ppc-le', 'ppc64', 'ppc64-le', 's390',
's390x'.

IgnoreSIGPIPE
Takes a boolean argument. If true, causes "SIGPIPE" to be ignored in the executed process. Defaults to
true because "SIGPIPE" generally is useful only in shell pipelines. Optional. Type boolean.

Nice
Sets the default nice level (scheduling priority) for executed processes. Takes an integer between -20
(highest priority) and 19 (lowest priority). See setpriority(2) for details. Optional. Type integer.

CPUSchedulingPolicy
Sets the CPU scheduling policy for executed processes. Takes one of "other", "batch", "idle", "fifo" or
"rr". See sched_setscheduler(2) for details. Optional. Type enum. choice: 'other', 'batch', 'idle',
'fifo', 'rr'.

CPUSchedulingPriority
Sets the CPU scheduling priority for executed processes. The available priority range depends on the
selected CPU scheduling policy (see above). For real-time scheduling policies an integer between 1
(lowest priority) and 99 (highest priority) can be used. See sched_setscheduler(2) for details.
Optional. Type uniline.

CPUSchedulingResetOnFork
Takes a boolean argument. If true, elevated CPU scheduling priorities and policies will be reset when the
executed processes fork, and can hence not leak into child processes. See sched_setscheduler(2) for
details. Defaults to false. Optional. Type boolean.

CPUAffinity
Controls the CPU affinity of the executed 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. See sched_setaffinity(2) for details. Optional. Type list of uniline.

IOSchedulingClass
Sets the I/O scheduling class for executed processes. Takes an integer between 0 and 3 or one of the
strings "none", "realtime", "best-effort" or "idle". See ioprio_set(2) for details. Optional. Type enum.
choice: '0', '1', '2', '3', 'none', 'realtime', 'best-effort', 'idle'.

IOSchedulingPriority
Sets the I/O scheduling priority for executed processes. Takes an integer between 0 (highest priority)
and 7 (lowest priority). The available priorities depend on the selected I/O scheduling class (see
above). See ioprio_set(2) for details. Optional. Type integer.

ProtectSystem
Takes a boolean argument or the special values "full" or "strict". If true, mounts the /usr and /boot
directories read-only for processes invoked by this unit. If set to "full", the /etc directory is mounted
read-only, too. If set to "strict" the entire file system hierarchy is mounted read-only, except for the
API file system subtrees /dev, /proc and /sys (protect these directories using "PrivateDevices",
"ProtectKernelTunables", "ProtectControlGroups"). This setting ensures that any modification of the
vendor-supplied operating system (and optionally its configuration, and local mounts) is prohibited for
the service. It is recommended to enable this setting for all long-running services, unless they are
involved with system updates or need to modify the operating system in other ways. If this option is
used, "ReadWritePaths" may be used to exclude specific directories from being made read-only. This
setting is implied if "DynamicUser" is set. For this setting the same restrictions regarding mount
propagation and privileges apply as for "ReadOnlyPaths" and related calls, see below. Defaults to off.
Optional. Type enum. choice: 'no', 'yes', 'full', 'strict'.

ProtectHome
Takes a boolean argument or "read-only". If true, the directories /home, /root and /run/user are made
inaccessible and empty for processes invoked by this unit. If set to "read-only", the three directories
are made read-only instead. It is recommended to enable this setting for all long-running services (in
particular network-facing ones), to ensure they cannot get access to private user data, unless the
services actually require access to the user's private data. This setting is implied if "DynamicUser" is
set. For this setting the same restrictions regarding mount propagation and privileges apply as for
"ReadOnlyPaths" and related calls, see below. Optional. Type enum. choice: 'no', 'yes', 'read-only'.

RuntimeDirectory
These options take a whitespace-separated list of directory names. The specified directory names must be
relative, and may not include "." or "..". If set, one or more directories by the specified names will be
created (including their parents) below /run (or $XDG_RUNTIME_DIR for user services), /var/lib (or
$XDG_CONFIG_HOME for user services), /var/cache (or $XDG_CACHE_HOME for user services), /var/log (or
$XDG_CONFIG_HOME/log for user services), or /etc (or $XDG_CONFIG_HOME for user services), respectively,
when the unit is started.

In case of "RuntimeDirectory" the lowest subdirectories are removed when the unit is stopped. It is
possible to preserve the specified directories in this case if "RuntimeDirectoryPreserve" is configured
to "restart" or "yes" (see below). The directories specified with "StateDirectory", "CacheDirectory",
"LogsDirectory", "ConfigurationDirectory" are not removed when the unit is stopped.

Except in case of "ConfigurationDirectory", the innermost specified directories will be owned by the user
and group specified in "User" and "Group". If the specified directories already exist and their owning
user or group do not match the configured ones, all files and directories below the specified directories
as well as the directories themselves will have their file ownership recursively changed to match what is
configured. As an optimization, if the specified directories are already owned by the right user and
group, files and directories below of them are left as-is, even if they do not match what is requested.
The innermost specified directories will have their access mode adjusted to the what is specified in
"RuntimeDirectoryMode", "StateDirectoryMode", "CacheDirectoryMode", "LogsDirectoryMode" and
"ConfigurationDirectoryMode".

These options imply "BindPaths" for the specified paths. When combined with "RootDirectory" or
"RootImage" these paths always reside on the host and are mounted from there into the unit's file system
namespace.

If "DynamicUser" is used in conjunction with "StateDirectory", "CacheDirectory" and "LogsDirectory" is
slightly altered: the directories are created below /var/lib/private, /var/cache/private and
/var/log/private, respectively, which are host directories made inaccessible to unprivileged users, which
ensures that access to these directories cannot be gained through dynamic user ID recycling. Symbolic
links are created to hide this difference in behaviour. Both from perspective of the host and from inside
the unit, the relevant directories hence always appear directly below /var/lib, /var/cache and /var/log.

Use "RuntimeDirectory" to manage one or more runtime directories for the unit and bind their lifetime to
the daemon runtime. This is particularly useful for unprivileged daemons that cannot create runtime
directories in /run due to lack of privileges, and to make sure the runtime directory is cleaned up
automatically after use. For runtime directories that require more complex or different configuration or
lifetime guarantees, please consider using tmpfiles.d(5).