systemd.kill

package: systemd

title: systemd.kill(5)

summary: Process killing procedure configuration

text:
# systemd.kill(5)

## NAME
systemd.kill - Process killing procedure configuration

## SYNOPSIS
service.service, socket.socket, mount.mount, swap.swap, scope.scope

## DESCRIPTION
Unit configuration files for services, sockets, mount points, swap devices and scopes share a subset of configuration options which define the killing procedure of processes belonging to the unit.

This man page lists the configuration options shared by these five unit types. See systemd.unit(5) for the common options shared by all unit configuration files, and systemd.service(5), systemd.socket(5), systemd.swap(5), systemd.mount(5) and systemd.scope(5) for more information on the configuration file options specific to each unit type.

The kill procedure configuration options are configured in the [Service], [Socket], [Mount] or [Swap] section, depending on the unit type.

## OPTIONS
KillMode=

Specifies how processes of this unit shall be killed. One of control-group, mixed, process, none. If set to control-group, all remaining processes in the control group of this unit will be killed on unit stop (for services: after the stop command is executed, as configured with ExecStop=). If set to mixed, the SIGTERM signal (see below) is sent to the main process while the subsequent SIGKILL signal (see below) is sent to all remaining processes of the unit's control group. If set to process, only the main process itself is killed (not recommended!). If set to none, no process is killed (strongly recommended against!). In this case, only the stop command will be executed on unit stop, but no process will be killed otherwise. Processes remaining alive after stop are left in their control group and the control group continues to exist after stop unless empty.

Note that it is not recommended to set KillMode= to process or even none, as this allows processes to escape the service manager's lifecycle and resource management, and to remain running even while their service is considered stopped and is assumed to not consume any resources.

Processes will first be terminated via SIGTERM (unless the signal to send is changed via KillSignal= or RestartKillSignal=). Optionally, this is immediately followed by a SIGHUP (if enabled with SendSIGHUP=). If processes still remain after:

•the main process of a unit has exited (applies to KillMode=: mixed)

•the delay configured via the TimeoutStopSec= has passed (applies to KillMode=: control-group, mixed, process)

the termination request is repeated with the SIGKILL signal or the signal specified via FinalKillSignal= (unless this is disabled via the SendSIGKILL= option). See kill(2) for more information.

Defaults to control-group.

Added in version 187.

KillSignal=

Specifies which signal to use when stopping a service. This controls the signal that is sent as first step of shutting down a unit (see above), and is usually followed by SIGKILL (see above and below). For a list of valid signals, see signal(7). Defaults to SIGTERM. Note that, right after sending the signal specified in this setting, systemd will always send SIGCONT, to ensure that even suspended tasks can be terminated cleanly.

Added in version 187.

RestartKillSignal=

Specifies which signal to use when restarting a service. The same as KillSignal= described above, with the exception that this setting is used in a restart job. Not set by default, and the value of KillSignal= is used. Added in version 244.

SendSIGHUP=

Specifies whether to send SIGHUP to remaining processes immediately after sending the signal configured with KillSignal=. This is useful to indicate to shells and shell-like programs that their connection has been severed. Takes a boolean value. Defaults to "no". Added in version 207.

SendSIGKILL=

Specifies whether to send SIGKILL (or the signal specified by FinalKillSignal=) to remaining processes after a timeout, if the normal shutdown procedure left processes of the service around. When disabled, a KillMode= of control-group or mixed service will not restart if processes from prior services exist within the control group. Takes a boolean value. Defaults to "yes". Added in version 187.

FinalKillSignal=

Specifies which signal to send to remaining processes after a timeout if SendSIGKILL= is enabled. The signal configured here should be one that is not typically caught and processed by services (SIGTERM is not suitable). Developers can find it useful to use this to generate a coredump to troubleshoot why a service did not terminate upon receiving the initial SIGTERM signal. This can be achieved by configuring LimitCORE= and setting FinalKillSignal= to either SIGQUIT or SIGABRT. Defaults to SIGKILL. Added in version 240.

WatchdogSignal=

Specifies which signal to use to terminate the service when the watchdog timeout expires (enabled through WatchdogSec=). Defaults to SIGABRT. Added in version 240.

## SEE ALSO
systemd(1), systemctl(1), journalctl(1), systemd.unit(5), systemd.service(5), systemd.socket(5), systemd.swap(5), systemd.mount(5), systemd.exec(5), systemd.directives(7), kill(2), signal(7)


systemd.mount

title: systemd.mount(5)

summary: Mount unit configuration

text:
# systemd.mount(5)

## NAME
systemd.mount - Mount unit configuration

## SYNOPSIS
mount.mount

## DESCRIPTION
A unit configuration file whose name ends in ".mount" encodes information about a file system mount point 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 mount specific configuration options are configured in the [Mount] section.

Additional options are listed in systemd.exec(5), which define the execution environment the mount(8) program is executed in, and in systemd.kill(5), which define the way the processes are terminated, and in systemd.resource-control(5), which configure resource control settings for the processes of the service.

Note that the options User= and Group= are not useful for mount units. systemd passes two parameters to mount(8); the values of What= and Where=. When invoked in this way, mount(8) does not read any options from /etc/fstab, and must be run as UID 0.

Mount units must be named after the mount point directories they control. Example: the mount point /home/lennart must be configured in a unit file home-lennart.mount. For details about the escaping logic used to convert a file system path to a unit name, see systemd.unit(5). Note that mount units cannot be templated, nor is possible to add multiple names to a mount unit by creating symlinks to its unit file.

Optionally, a mount unit may be accompanied by an automount unit, to allow on-demand or parallelized mounting. See systemd.automount(5).

Mount points created at runtime (independently of unit files or /etc/fstab) will be monitored by systemd and appear like any other mount unit in systemd. See /proc/self/mountinfo description in proc(5).

Some file systems have special semantics as API file systems for kernel-to-userspace and userspace-to-userspace interfaces. Some of them may not be changed via mount units, and cannot be disabled. For a longer discussion see API File Systems[1].

The systemd-mount(1) command allows creating .mount and .automount units dynamically and transiently from the command line.

## AUTOMATIC DEPENDENCIES

### Implicit Dependencies
The following dependencies are implicitly added:

•If a mount unit is beneath another mount unit in the file system hierarchy, both a requirement dependency and an ordering dependency between both units are created automatically.

•Block device backed file systems automatically gain Requires=, StopPropagatedFrom=, and After= type dependencies on the device unit encapsulating the block device (see x-systemd.device-bound= for details).

•If traditional file system quota is enabled for a mount unit, automatic Wants= and Before= dependencies on systemd-quotacheck.service and quotaon.service are added.

•Additional implicit dependencies may be added as result of execution and resource control parameters as documented in systemd.exec(5) and systemd.resource-control(5).

### Default Dependencies
The following dependencies are added unless DefaultDependencies=no is set:

•All mount units acquire automatic Before= and Conflicts= on umount.target in order to be stopped during shutdown.

•Mount units referring to local file systems automatically gain an After= dependency on local-fs-pre.target, and a Before= dependency on local-fs.target unless one or more mount options among nofail, x-systemd.wanted-by=, and x-systemd.required-by= is set. See below for detailed information. Additionally, an After= dependency on swap.target is added when the file system type is "tmpfs".

•Network mount units automatically acquire After= dependencies on remote-fs-pre.target, network.target, plus After= and Wants= dependencies on network-online.target, and a Before= dependency on remote-fs.target, unless one or more mount options among nofail, x-systemd.wanted-by=, and x-systemd.required-by= is set.

Mount units referring to local and network file systems are distinguished by their file system type specification. In some cases this is not sufficient (for example network block device based mounts, such as iSCSI), in which case _netdev may be added to the mount option string of the unit, which forces systemd to consider the mount unit a network mount.

## FSTAB
Mount units may either be configured via unit files, or via /etc/fstab (see fstab(5) for details). Mounts listed in /etc/fstab will be converted into native units dynamically at boot and when the configuration of the system manager is reloaded. In general, configuring mount points through /etc/fstab is the preferred approach to manage mounts for humans. For tooling, writing mount units should be preferred over editing /etc/fstab. See systemd-fstab-generator(8) for details about the conversion from /etc/fstab to mount units.

The NFS mount option bg for NFS background mounts as documented in nfs(5) is detected by systemd-fstab-generator and the options are transformed so that systemd fulfills the job-control implications of that option. Specifically systemd-fstab-generator acts as though "x-systemd.mount-timeout=infinity,retry=10000" was prepended to the option list, and "fg,nofail" was appended. Depending on specific requirements, it may be appropriate to provide some of these options explicitly, or to make use of the "x-systemd.automount" option described below instead of using "bg".

When reading /etc/fstab a few special mount options are understood by systemd which influence how dependencies are created for mount points. systemd will create a dependency of type Wants= or Requires= (see option nofail below), from either local-fs.target or remote-fs.target, depending whether the file system is local or remote.

x-systemd.requires=

Configures a Requires= and an After= dependency between the created mount unit and another systemd unit, such as a device or mount unit. The argument should be a unit name, or an absolute path to a device node or mount point. This option may be specified more than once. This option is particularly useful for mount point declarations that need an additional device to be around (such as an external journal device for journal file systems) or an additional mount to be in place (such as an overlay file system that merges multiple mount points). See After= and Requires= in systemd.unit(5) for details. Note that this option always applies to the created mount unit only regardless whether x-systemd.automount has been specified.

Added in version 220.

x-systemd.wants=

Configures a Wants= and an After= dependency between the created mount unit and another systemd unit, similar to the x-systemd.requires= option. Added in version 257.

x-systemd.before=, x-systemd.after=

In the created mount unit, configures a Before= or After= dependency on another systemd unit, such as a mount unit. The argument should be a unit name or an absolute path to a mount point. This option may be specified more than once. This option is particularly useful for mount point declarations with nofail option that are mounted asynchronously but need to be mounted before or after some unit start, for example, before local-fs.target unit. See Before= and After= in systemd.unit(5) for details. Note that these options always apply to the created mount unit only regardless whether x-systemd.automount has been specified.

Added in version 233.

x-systemd.wanted-by=, x-systemd.required-by=

In the created mount unit, configures a WantedBy= or RequiredBy= dependency on another unit. This option may be specified more than once. If this is specified, the default dependencies (see above) other than umount.target on the created mount unit, e.g. local-fs.target, are not automatically created. Hence it is likely that some ordering dependencies need to be set up manually through x-systemd.before= and x-systemd.after=. See WantedBy= and RequiredBy= in systemd.unit(5) for details. Added in version 245.

x-systemd.wants-mounts-for=, x-systemd.requires-mounts-for=

Configures a RequiresMountsFor= or WantsMountsFor= dependency between the created mount unit and other mount units. The argument must be an absolute path. This option may be specified more than once. See RequiresMountsFor= or WantsMountsFor= in systemd.unit(5) for details. Added in version 220.

x-systemd.device-bound=

Takes a boolean argument. If true or no argument, a BindsTo= dependency on the backing device is set. If false, the mount unit is not stopped no matter whether the backing device is still present. This is useful when the file system is backed by volume managers. If not set, and the mount comes from unit fragments, i.e. generated from /etc/fstab by systemd-fstab-generator(8) or loaded from a manually configured mount unit, a combination of Requires= and StopPropagatedFrom= dependencies is set on the backing device, otherwise only Requires= is used. Added in version 233.

x-systemd.automount

An automount unit will be created for the file system. See systemd.automount(5) for details. Added in version 215.

x-systemd.idle-timeout=

Configures the idle timeout of the automount unit. See TimeoutIdleSec= in systemd.automount(5) for details. Added in version 220.

x-systemd.device-timeout=

Configure how long systemd should wait for a device to show up before giving up on an entry from /etc/fstab. Specify a time in seconds or explicitly append a unit such as "s", "min", "h", "ms". Note that this option can only be used in /etc/fstab, and will be ignored when part of the Options= setting in a unit file.

Added in version 215.

x-systemd.mount-timeout=

Configure how long systemd should wait for the mount command to finish before giving up on an entry from /etc/fstab. Specify a time in seconds or explicitly append a unit such as "s", "min", "h", "ms". Note that this option can only be used in /etc/fstab, and will be ignored when part of the Options= setting in a unit file.

See TimeoutSec= below for details.

Added in version 233.

x-systemd.makefs

The file system will be initialized on the device. If the device is not "empty", i.e. it contains any signature, the operation will be skipped. It is hence expected that this option remains set even after the device has been initialized. Note that this option can only be used in /etc/fstab, and will be ignored when part of the Options= setting in a unit file.

See systemd-makefs@.service(8).

wipefs(8) may be used to remove any signatures from a block device to force x-systemd.makefs to reinitialize the device.

Added in version 236.

x-systemd.growfs

The file system will be grown to occupy the full block device. If the file system is already at maximum size, no action will be performed. It is hence expected that this option remains set even after the file system has been grown. Only certain file system types are supported, see systemd-makefs@.service(8) for details. Note that this option can only be used in /etc/fstab, and will be ignored when part of the Options= setting in a unit file.

Added in version 236.

x-systemd.pcrfs

Measures file system identity information (mount point, type, label, UUID, partition label, partition UUID) into PCR 15 after the file system has been mounted. This ensures the systemd-pcrfs@.service(8) or systemd-pcrfs-root.service services are pulled in by the mount unit. Note that this option can only be used in /etc/fstab, and will be ignored when part of the Options= setting in a unit file. It is also implied for the root and /usr/ partitions discovered by systemd-gpt-auto-generator(8).

Added in version 253.

x-systemd.rw-only

If a mount operation fails to mount the file system read-write, it normally tries mounting the file system read-only instead. This option disables that behaviour, and causes the mount to fail immediately instead. This option is translated into the ReadWriteOnly= setting in a unit file. Added in version 246.

_netdev

Normally the file system type is used to determine if a mount is a "network mount", i.e. if it should only be started after the network is available. Using this option overrides this detection and specifies that the mount requires network. Network mount units are ordered between remote-fs-pre.target and remote-fs.target, instead of local-fs-pre.target and local-fs.target. They also pull in network-online.target and are ordered after it and network.target.

Added in version 235.

noauto, auto

With noauto, the mount unit will not be added as a dependency for local-fs.target or remote-fs.target. This means that it will not be mounted automatically during boot, unless it is pulled in by some other unit. The auto option has the opposite meaning and is the default. Note that if x-systemd.automount (see above) is used, neither auto nor noauto have any effect. The matching automount unit will be added as a dependency to the appropriate target.

Added in version 215.

nofail

With nofail, this mount will be only wanted, not required, by local-fs.target or remote-fs.target. Moreover, the mount unit is not ordered before these target units. This means that the boot will continue without waiting for the mount unit and regardless whether the mount point can be mounted successfully. Added in version 215.

x-initrd.mount

An additional filesystem to be mounted in the initrd. See initrd-fs.target description in systemd.special(7). This is both an indicator to the initrd to mount this partition early and an indicator to the host to leave the partition mounted until final shutdown. Or in other words, if this flag is set it is assumed the mount shall be active during the entire regular runtime of the system, i.e. established before the initrd transitions into the host all the way until the host transitions to the final shutdown phase. Added in version 215.

If a mount point is configured in both /etc/fstab and a unit file that is stored below /usr/, the former will take precedence. If the unit file is stored below /etc/, it will take precedence. This means: native unit files take precedence over traditional configuration files, but this is superseded by the rule that configuration in /etc/ will always take precedence over configuration in /usr/.

## OPTIONS
Mount unit files may include [Unit] and [Install] sections, which are described in systemd.unit(5).

Mount unit files must include a [Mount] section, which carries information about the file system mount points it supervises. A number of options that may be used in this section are shared with other unit types. These options are documented in systemd.exec(5), systemd.kill(5) and systemd.resource-control(5). The options specific to the [Mount] section of mount units are the following:

What=

Takes an absolute path or a fstab-style identifier of a device node, file or other resource to mount. See mount(8) for details. If this refers to a device node, a dependency on the respective device unit is automatically created. (See systemd.device(5) for more information.) This option is mandatory. Note that the usual specifier expansion is applied to this setting, literal percent characters should hence be written as "%%". If this mount is a bind mount and the specified path does not exist yet it is created as directory.

Where=

Takes an absolute path of a file or directory for the mount point; in particular, the destination cannot be a symbolic link. If the mount point does not exist at the time of mounting, it is created as either a directory or a file. The former is the usual case; the latter is done only if this mount is a bind mount and the source (What=) is not a directory. This string must be reflected in the unit filename. (See above.) This option is mandatory.

Type=

Takes a string for the file system type. See mount(8) for details. This setting is optional. If the type is "overlay", and "upperdir=" or "workdir=" are specified as options and the directories do not exist, they will be created.

Options=

Mount options to use when mounting. This takes a comma-separated list of options. This setting is optional. Note that the usual specifier expansion is applied to this setting, literal percent characters should hence be written as "%%".

SloppyOptions=

Takes a boolean argument. If true, parsing of the options specified in Options= is relaxed, and unknown mount options are tolerated. This corresponds with mount(8)'s -s switch. Defaults to off. Added in version 215.

LazyUnmount=

Takes a boolean argument. If true, detach the filesystem from the filesystem hierarchy at time of the unmount operation, and clean up all references to the filesystem as soon as they are not busy anymore. This corresponds with umount(8)'s -l switch. Defaults to off. Added in version 232.

ReadWriteOnly=

Takes a boolean argument. If false, a mount point that shall be mounted read-write but cannot be mounted so is retried to be mounted read-only. If true the operation will fail immediately after the read-write mount attempt did not succeed. This corresponds with mount(8)'s -w switch. Defaults to off. Added in version 246.

ForceUnmount=

Takes a boolean argument. If true, force an unmount (in case of an unreachable NFS system). This corresponds with umount(8)'s -f switch. Defaults to off. Added in version 232.

DirectoryMode=

Directories of mount points (and any parent directories) are automatically created if needed. This option specifies the file system access mode used when creating these directories. Takes an access mode in octal notation. Defaults to 0755.

TimeoutSec=

Configures the time to wait for the mount command to finish. If a command does not exit within the configured time, the mount will be considered failed and be shut down again. All commands still running will be terminated forcibly via SIGTERM, and after another delay of this time with SIGKILL. (See KillMode= in systemd.kill(5).) Takes a unit-less value in seconds, or a time span value such as "5min 20s". Pass 0 to disable the timeout logic. The default value is set from DefaultTimeoutStartSec= option in systemd-system.conf(5).

Check systemd.unit(5), systemd.exec(5), and systemd.kill(5) for more settings.

## SEE ALSO
systemd(1), systemctl(1), systemd-system.conf(5), systemd.unit(5), systemd.exec(5), systemd.kill(5), systemd.resource-control(5), systemd.service(5), systemd.device(5), proc(5), mount(8), systemd-fstab-generator(8), systemd.directives(7), systemd-mount(1)

## NOTES
1.

API File Systems

https://systemd.io/API_FILE_SYSTEMS


systemd.path

title: systemd.path(5)

summary: Path unit configuration

text:
# systemd.path(5)

## NAME
systemd.path - Path unit configuration

## SYNOPSIS
path.path

## DESCRIPTION
A unit configuration file whose name ends in ".path" encodes information about a path monitored by systemd, for path-based activation.

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 path specific configuration options are configured in the [Path] section.

For each path file, a matching unit file must exist, describing the unit to activate when the path changes. By default, a service by the same name as the path (except for the suffix) is activated. Example: a path file foo.path activates a matching service foo.service. The unit to activate may be controlled by Unit= (see below).

Internally, path units use the inotify(7) API to monitor file systems. Due to that, it suffers by the same limitations as inotify, and for example cannot be used to monitor files or directories changed by other machines on remote NFS file systems.

When a service unit triggered by a path unit terminates (regardless whether it exited successfully or failed), monitored paths are checked immediately again, and the service accordingly restarted instantly. As protection against busy looping in this trigger/start cycle, a start rate limit is enforced on the service unit, see StartLimitIntervalSec= and StartLimitBurst= in systemd.unit(5). Unlike other service failures, the error condition that the start rate limit is hit is propagated from the service unit to the path unit and causes the path unit to fail as well, thus ending the loop.

## AUTOMATIC DEPENDENCIES

### Implicit Dependencies
The following dependencies are implicitly added:

•If a path unit is beneath another mount unit in the file system hierarchy, both a requirement and an ordering dependency between both units are created automatically.

•An implicit Before= dependency is added between a path unit and the unit it is supposed to activate.

### Default Dependencies
The following dependencies are added unless DefaultDependencies=no is set:

•Path units will automatically have dependencies of type Before= on paths.target, dependencies of type After= and Requires= on sysinit.target, and have dependencies of type Conflicts= and Before= on shutdown.target. These ensure that path units are terminated cleanly prior to system shutdown. Only path units involved with early boot or late system shutdown should disable DefaultDependencies= option.

## OPTIONS
Path unit files may include [Unit] and [Install] sections, which are described in systemd.unit(5).

Path unit files must include a [Path] section, which carries information about the path or paths it monitors. The options specific to the [Path] section of path units are the following:

PathExists=, PathExistsGlob=, PathChanged=, PathModified=, DirectoryNotEmpty=

Defines paths to monitor for certain changes: PathExists= may be used to watch the mere existence of a file or directory. If the file specified exists, the configured unit is activated. PathExistsGlob= works similarly, but checks for the existence of at least one file matching the globbing pattern specified. PathChanged= may be used to watch a file or directory and activate the configured unit whenever it changes. It is not activated on every write to the watched file but it is activated if the file which was open for writing gets closed. PathModified= is similar, but additionally it is activated also on simple writes to the watched file. DirectoryNotEmpty= may be used to watch a directory and activate the configured unit whenever it contains at least one file. The arguments of these directives must be absolute file system paths.

Multiple directives may be combined, of the same and of different types, to watch multiple paths. If the empty string is assigned to any of these options, the list of paths to watch is reset, and any prior assignments of these options will not have any effect.

If a path already exists (in case of PathExists= and PathExistsGlob=) or a directory already is not empty (in case of DirectoryNotEmpty=) at the time the path unit is activated, then the configured unit is immediately activated as well. Something similar does not apply to PathChanged= and PathModified=.

If the path itself or any of the containing directories are not accessible, systemd will watch for permission changes and notice that conditions are satisfied when permissions allow that.

Note that files whose name starts with a dot (i.e. hidden files) are generally ignored when monitoring these paths.

Unit=

The unit to activate when any of the configured paths changes. The argument is a unit name, whose suffix is not ".path". If not specified, this value defaults to a service that has the same name as the path unit, except for the suffix. (See above.) It is recommended that the unit name that is activated and the unit name of the path unit are named identical, except for the suffix.

MakeDirectory=

Takes a boolean argument. If true, the directories to watch are created before watching. This option is ignored for PathExists= settings. Defaults to false.

DirectoryMode=

If MakeDirectory= is enabled, use the mode specified here to create the directories in question. Takes an access mode in octal notation. Defaults to 0755.

TriggerLimitIntervalSec=, TriggerLimitBurst=

Configures a limit on how often this path unit may be activated within a specific time interval. The TriggerLimitIntervalSec= may be used to configure the length of the time interval in the usual time units "us", "ms", "s", "min", "h", ... and defaults to 2s. See systemd.time(7) for details on the various time units understood. The TriggerLimitBurst= setting takes a positive integer value and specifies the number of permitted activations per time interval, and defaults to 200. Set either to 0 to disable any form of trigger rate limiting. If the limit is hit, the unit is placed into a failure mode, and will not watch the paths anymore until restarted. Note that this limit is enforced before the service activation is enqueued. Added in version 250.

Check systemd.unit(5), systemd.exec(5), and systemd.kill(5) for more settings.

## SEE ALSO
Environment variables with details on the trigger will be set for triggered units. See the section "Environment Variables Set or Propagated by the Service Manager" in systemd.exec(5) for more details.

systemd(1), systemctl(1), systemd.unit(5), systemd.service(5), inotify(7), systemd.directives(7)


systemd.pcrlock

title: systemd.pcrlock(5)

summary: PCR measurement prediction files

text:
# systemd.pcrlock(5)

## NAME
systemd.pcrlock, systemd.pcrlock.d - PCR measurement prediction files

## SYNOPSIS
/etc/pcrlock.d/*.pcrlock

/etc/pcrlock.d/*.pcrlock.d/*.pcrlock

/run/pcrlock.d/*.pcrlock

/run/pcrlock.d/*.pcrlock.d/*.pcrlock

/var/lib/pcrlock.d/*.pcrlock

/var/lib/pcrlock.d/*.pcrlock.d/*.pcrlock

/usr/local/pcrlock.d/*.pcrlock

/usr/local/pcrlock.d/*.pcrlock.d/*.pcrlock

/usr/lib/pcrlock.d/*.pcrlock

/usr/lib/pcrlock.d/*.pcrlock.d/*.pcrlock

## DESCRIPTION
*.pcrlock files define expected TPM2 PCR measurements of components involved in the boot process. systemd-pcrlock(8) uses such pcrlock files to analyze and predict TPM2 PCR measurements. The pcrlock files are JSON arrays that follow a subset of the TCG Canonical Event Log Format (CEL-JSON)[1] specification. Specifically the "recnum", "content", and "content_type" record fields are not used and ignored if present. Each pcrlock file defines one set of expected, ordered PCR measurements of a specific component of the boot.

*.pcrlock files may be placed in various .d/ drop-in directories (see above for a full list). All matching files discovered in these directories are sorted alphabetically by their file name (without taking the actual directory they were found in into account): pcrlock files with alphabetically earlier names are expected to cover measurements done before those with alphabetically later names. In order to make positioning pcrlock files in the boot process convenient the files are expected (by convention, this is not enforced) to be named "NNN-component.pcrlock" (where NNN is a three-digit decimal number), for example 750-enter-initrd.pcrlock.

For various components of the boot process more than one alternative pcrlock file shall be supported (i.e. "variants"). For example to cover multiple kernels installed in parallel in the access policy, or multiple versions of the boot loader. This can be done by placing *.pcrlock.d/*.pcrlock in the drop-in dirs, i.e. a common directory for a specific component, that contains one or more pcrlock files each covering one variant of the component. Example: 650-kernel.pcrlock.d/6.5.5-200.fc38.x86_64.pcrlock and 650-kernel.pcrlock.d/6.5.7-100.fc38.x86_64.pcrlock

Use systemd-pcrlock list-components to list all pcrlock files currently installed.

Use the various lock-* commands of systemd-pcrlock to automatically generate suitable pcrlock files for various types of resources.

## WELL-KNOWN COMPONENTS
Components of the boot process may be defined freely by the administrator or OS vendor. The following components are well-known however, and are defined by systemd. The list below is useful for ordering local pcrlock files properly against these components of the boot.

240-secureboot-policy.pcrlock

The SecureBoot policy, as recorded to PCR 7. May be generated via systemd-pcrlock lock-secureboot-policy. Added in version 255.

250-firmware-code-early.pcrlock

Firmware code measurements, as recorded to PCR 0 and 2, up to the separator measurement (see 400-secureboot-separator.pcrlock below). May be generated via systemd-pcrlock lock-firmware-code. Added in version 255.

250-firmware-config-early.pcrlock

Firmware configuration measurements, as recorded to PCR 1 and 3, up to the separator measurement (see 400-secureboot-separator.pcrlock below). May be generated via systemd-pcrlock lock-firmware-config. Added in version 255.

350-action-efi-application.pcrlock

The EFI "Application" measurement done once by the firmware. Statically defined. Added in version 255.

400-secureboot-separator.pcrlock

The EFI "separator" measurement on PCR 7 done once by the firmware to indicate where firmware control transitions into boot loader/OS control. Statically defined. Added in version 255.

500-separator.pcrlock

The EFI "separator" measurements on PCRs 0-6 done once by the firmware to indicate where firmware control transitions into boot loader/OS control. Statically defined. Added in version 255.

550-firmware-code-late.pcrlock

Firmware code measurements, as recorded to PCR 0 and 2, after the separator measurement (see 400-secureboot-separator.pcrlock above). May be generated via systemd-pcrlock lock-firmware-code. Added in version 255.

550-firmware-config-late.pcrlock

Firmware configuration measurements, as recorded to PCR 1 and 3, after the separator measurement (see 400-secureboot-separator.pcrlock above). May be generated via systemd-pcrlock lock-firmware-config. Added in version 255.

600-gpt.pcrlock

The GPT partition table of the booted medium, as recorded to PCR 5 by the firmware. May be generated via systemd-pcrlock lock-gpt. Added in version 255.

620-secureboot-authority.pcrlock

The SecureBoot authority, as recorded to PCR 7. May be generated via systemd-pcrlock lock-secureboot-authority. Added in version 255.

700-action-efi-exit-boot-services.pcrlock

The EFI action generated when ExitBootServices() is generated, i.e. when the UEFI environment is left and the OS takes over. Covers the PCR 5 measurement. Statically defined. Added in version 255.

710-kernel-cmdline.pcrlock

The kernel command line, as measured by the Linux kernel to PCR 9. May be generated via systemd-pcrlock lock-kernel-cmdline. Added in version 255.

720-kernel-initrd.pcrlock

The kernel initrd, as measured by the Linux kernel to PCR 9. May be generated via systemd-pcrlock lock-kernel-initrd. Added in version 255.

750-enter-initrd.pcrlock

The measurement to PCR 11 systemd-pcrphase-initrd.service(8) makes when the initrd initializes. Statically defined. Added in version 255.

800-leave-initrd.pcrlock

The measurement to PCR 11 systemd-pcrphase-initrd.service(8) makes when the initrd finishes. Statically defined. Added in version 255.

820-machine-id.pcrlock

The measurement to PCR 15 systemd-pcrmachine.service(8) makes at boot, covering /etc/machine-id contents. May be generated via systemd-pcrlock lock-machine-id. Added in version 255.

830-root-file-system.pcrlock

The measurement to PCR 15 systemd-pcrfs-root.service(8) makes at boot, covering the root file system identity. May be generated via systemd-pcrlock lock-file-system. Added in version 255.

850-sysinit.pcrlock

The measurement to PCR 11 systemd-pcrphase-sysinit.service(8) makes when the main userspace did basic initialization and will now proceed to start regular system services. Statically defined. Added in version 255.

900-ready.pcrlock

The measurement to PCR 11 systemd-pcrphase.service(8) makes when the system fully booted up. Statically defined. Added in version 255.

950-shutdown.pcrlock

The measurement to PCR 11 systemd-pcrphase.service(8) makes when the system begins shutdown. Statically defined. Added in version 255.

990-final.pcrlock

The measurement to PCR 11 systemd-pcrphase-sysinit.service(8) makes when the system is close to finishing shutdown. Statically defined. Added in version 255.

## SEE ALSO
systemd(1), systemd-pcrlock(8)

## NOTES
1.

TCG Canonical Event Log Format (CEL-JSON)

https://trustedcomputinggroup.org/resource/canonical-event-log-format/


systemd.preset

title: systemd.preset(5)

summary: Service enablement presets

text:
# systemd.preset(5)

## NAME
systemd.preset - Service enablement presets

## SYNOPSIS
/etc/systemd/system-preset/*.preset

/run/systemd/system-preset/*.preset

/usr/local/lib/systemd/system-preset/*.preset

/usr/lib/systemd/system-preset/*.preset

/etc/systemd/user-preset/*.preset

/run/systemd/user-preset/*.preset

/usr/local/lib/systemd/user-preset/*.preset

/usr/lib/systemd/user-preset/*.preset

## DESCRIPTION
Preset files may be used to encode policy which units shall be enabled by default and which ones shall be disabled. They are read by systemctl preset which uses this information to enable or disable a unit. Depending on that policy, systemctl preset is identical to systemctl enable or systemctl disable. systemctl preset is used by the post install scriptlets of rpm packages (or other OS package formats), to enable/disable specific units by default on package installation, enforcing distribution, spin, or administrator preset policy. This allows choosing a certain set of units to be enabled/disabled even before installing the actual package. For more information, see systemctl(1).

It is not recommended to ship preset files within the respective software packages implementing the units, but rather centralize them in a distribution or spin default policy, which can be amended by administrator policy, see below.

If no preset files exist, preset operations will enable all units that are installed by default. If this is not desired and all units shall rather be disabled, it is necessary to ship a preset file with a single, catchall "disable *" line. (See example 1, below.)

When the machine is booted for the first time, systemd(1) will enable/disable all units according to preset policy, similarly to systemctl preset-all. Also see ConditionFirstBoot= in systemd.unit(5) and "First Boot Semantics" in machine-id(5).

## PRESET FILE FORMAT
The preset files contain a list of directives, one per line. Empty lines and lines whose first non-whitespace character is "#" or ";" are ignored. Each directive consists of one of the words "enable", "disable", or "ignore", followed by whitespace and a unit name. The unit name may contain shell-style wildcards.

For the enable directive for template units, one or more instance names may be specified as a space-separated list after the unit name. In this case, those instances will be enabled instead of the instance specified via DefaultInstance= in the unit.

Presets must refer to the "real" unit file, and not to any aliases. See systemd.unit(5) for a description of unit aliasing.

Three different directives are understood: "enable" may be used to enable units by default, "disable" to disable units by default, and "ignore" to ignore units and leave existing configuration intact.

If multiple lines apply to a unit name, the first matching one takes precedence over all others.

Each preset file shall be named in the style of <priority>-<policy-name>.preset. Files in /etc/ override files with the same name in /usr/lib/ and /run/. Files in /run/ override files with the same name in /usr/lib/. Packages should install their preset files in /usr/lib/. Files in /etc/ are reserved for the local administrator, who may use this logic to override the preset files installed by vendor packages. All preset files are sorted by their filename in lexicographic order, regardless of which of the directories they reside in. If multiple files specify the same unit name, the entry in the file with the lexicographically earliest name will be applied. It is recommended to prefix all filenames with a two-digit number and a dash, to simplify the ordering of the files.

If the administrator wants to disable a preset file supplied by the vendor, the recommended way is to place a symlink to /dev/null in /etc/systemd/system-preset/ bearing the same filename.

## EXAMPLES
Example 1. Default to off

```
# /usr/lib/systemd/system-preset/99-default.preset
disable *
```

This disables all units. Due to the filename prefix "99-", it will be read last and hence can easily be overridden by spin or administrator preset policy.

Example 2. Enable multiple template instances

```
# /usr/lib/systemd/system-preset/80-dirsrv.preset
enable dirsrv@.service foo bar baz
```

This enables all three of dirsrv@foo.service, dirsrv@bar.service and dirsrv@baz.service.

Example 3. A GNOME spin

```
# /usr/lib/systemd/system-preset/50-gnome.preset
enable gdm.service
enable colord.service
enable accounts-daemon.service
enable avahi-daemon.*
```

This enables the three mentioned units, plus all avahi-daemon regardless of which unit type. A file like this could be useful for inclusion in a GNOME spin of a distribution. It will ensure that the units necessary for GNOME are properly enabled as they are installed. It leaves all other units untouched, and subject to other (later) preset files, for example like the one from the first example above.

Example 4. Administrator policy

```
# /etc/systemd/system-preset/00-lennart.preset
enable httpd.service
enable sshd.service
enable postfix.service
disable *
```

This enables three specific services and disables all others. This is useful for administrators to specifically select the units to enable, and disable all others. Due to the filename prefix "00-" it will be read early and override all other preset policy files.

## MOTIVATION FOR THE PRESET LOGIC
Different distributions have different policies on which services shall be enabled by default when the package they are shipped in is installed. On Fedora all services stay off by default, so that installing a package will not cause a service to be enabled (with some exceptions). On Debian all services are immediately enabled by default, so that installing a package will cause its services to be enabled right-away.

Even within a single distribution, different spins (flavours, remixes, whatever you might want to call them) of a distribution also have different policies on what services to enable, and what services to leave off. For example, Fedora Workstation will enable gdm as display manager by default, while the Fedora KDE spin will enable sddm instead.

Different sites might also have different policies what to turn on by default and what to turn off. For example, one administrator would prefer to enforce the policy of "sshd should be always on, but everything else off", while another one might say "snmpd always on, and for everything else use the distribution policy defaults".

Traditionally, policy about which services shall be enabled were implemented in each package individually. This made it cumbersome to implement different policies per spin or per site, or to create software packages that do the right thing on more than one distribution. The enablement mechanism was also encoding the enablement policy.

The preset mechanism allows clean separation of the enablement mechanism (inside the package scriptlets, by invoking systemctl preset) and enablement policy (centralized in the preset files), and lifts the configuration out of individual packages. Preset files may be written for specific distributions, for specific spins or for specific sites, in order to enforce different policies as needed. It is recommended to apply the policy encoded in preset files in package installation scriptlets.

## SEE ALSO
systemd(1), systemctl(1), systemd-delta(1)

daemon(7) has a discussion of packaging scriptlets.

Fedora page introducing the use of presets: Features/PackagePresets[1].

## NOTES
1.

Features/PackagePresets

https://fedoraproject.org/wiki/Features/PackagePresets