X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=man%2Fsystemd.unit.xml;h=55569681cf43164801073c55ed186b7cceccb3a5;hp=0ca18bd317ae4f6fde00d3005b4d2be66f9d00a8;hb=6569cae18ed640a4e9f52f73e2a3ec54b07d0406;hpb=8092a428d40ac682df9e80c36988043854579679 diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml index 0ca18bd31..55569681c 100644 --- a/man/systemd.unit.xml +++ b/man/systemd.unit.xml @@ -8,16 +8,16 @@ Copyright 2010 Lennart Poettering systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 2 of the License, or + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - General Public License for more details. + Lesser General Public License for more details. - You should have received a copy of the GNU General Public License + You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see . --> @@ -44,7 +44,7 @@ systemd.unit - systemd unit configuration files + Unit configuration @@ -121,8 +121,9 @@ If a line starts with followed by a file name, the specified file will be - read as if its contents were listed in place of the - directive. + parsed at this point. Make sure that the file that is + included has the appropriate section headers before + any directives. Along with a unit file foo.service a directory @@ -180,30 +181,116 @@ and no file by that name is found, systemd will look for getty@.service and instantiate a service from that configuration file if - it is found. To refer to the instance string from + it is found. + + To refer to the instance string from within the configuration file you may use the special %i specifier in many of the - configuration options. Other specifiers that may be - used are %n, %N, - %p, %P, - %I, %f, - %c, %r, - %R and %t for - the full unit name, the unescaped unit name, the - prefix name, the unescaped prefix name, the unescaped - instance name, the unescaped filename, the control - group path of the unit, the root control group path of - systemd, and the parent directory of the root control - cgroup path of systemd and the runtime socket dir, - respectively. The unescaped filename is either the - unescaped instance name (if set) with / prepended (if - necessary), or the prefix name similarly prepended - with /. The prefix name here refers to the string - before the @, i.e. "getty" in the example above, where - "tty3" is the instance name. The runtime socket - directory is either /run (for the - system manager) or $XDG_RUNTIME_DIR - (for user managers). + configuration options. Other specifiers exist, the + full list is: + + + Specifiers available in unit files + + + + + + + Specifier + Meaning + Details + + + + + %n + Full unit name + + + + %N + Unescaped full unit name + + + + %p + Prefix name + This refers to the string before the @, i.e. "getty" in the example above, where "tty3" is the instance name. + + + %P + Unescaped prefix name + + + + %i + Instance name + This is the string between the @ character and the suffix. + + + %I + Unescaped instance name + + + + %f + Unescaped file name + This is either the unescaped instance name (if set) with / prepended (if necessary), or the prefix name similarly prepended with /. + + + %c + Control group path of the unit + + + + %r + Root control group path of systemd + + + + %R + Parent directory of the root control group path of systemd + + + + %t + Runtime socket dir + This is either /run (for the system manager) or $XDG_RUNTIME_DIR (for user managers). + + + %u + User name + This is the name of the configured user of the unit, or (if none is set) the user running the systemd instance. + + + %h + User home directory + This is the home directory of the configured user of the unit, or (if none is set) the user running the systemd instance. + + + %s + User shell + This is the shell of the configured user of the unit, or (if none is set) the user running the systemd instance. + + + %m + Machine ID + The machine ID of the running system, formatted as string. See machine-id5 for more information. + + + %b + Boot ID + The boot ID of the running system, formatted as string. See random4 for more information. + + + %H + Host name + The host name of the running system. + + + +
If a unit file is empty (i.e. has the file size 0) or is symlinked to /dev/null @@ -237,6 +324,23 @@ name. + + Documentation= + A space separated list + of URIs referencing documentation for + this unit or its + configuration. Accepted are only URIs + of the types + http://, + https://, + file:, + info:, + man:. For more + information about the syntax of these + URIs see + uri7. + + Requires= @@ -274,7 +378,15 @@ Requires= in order to achieve a system that is more robust when dealing with failing - services. + services. + + Note that dependencies of this + type may also be configured outside of + the unit configuration file by + adding a symlink to a + .requires/ directory + accompanying the unit file. For + details see above. @@ -326,7 +438,9 @@ the transaction as a whole. This is the recommended way to hook start-up of one unit to the start-up of another - unit. Note that dependencies of this + unit. + + Note that dependencies of this type may also be configured outside of the unit configuration file by adding a symlink to a @@ -336,12 +450,12 @@ - BindTo= + BindsTo= Configures requirement dependencies, very similar in style to Requires=, however - in addition to this behaviour it also + in addition to this behavior it also declares that this unit is stopped when any of the units listed suddenly disappears. Units can suddenly, @@ -352,6 +466,21 @@ systemd. + + PartOf= + + Configures dependencies + similar to Requires=, + but limited to stopping and restarting + of units. When systemd stops or restarts + the units listed here, the action is + propagated to this unit. + Note that this is a one way dependency - + changes to this unit do not affect the + listed units. + + + Conflicts= @@ -452,6 +581,34 @@ state. + + PropagatesReloadTo= + ReloadPropagatedFrom= + + Lists one or more + units where reload requests on the + unit will be propagated to/on the + other unit will be propagated + from. Issuing a reload request on a + unit will automatically also enqueue a + reload request on all units that the + reload request shall be propagated to + via these two + settings. + + + + RequiresMountsFor= + + Takes a space + separated list of absolute paths. Automatically + adds dependencies of type + Requires= and + After= for all + mount units required to access the + specified path. + + OnFailureIsolate= @@ -485,8 +642,8 @@ argument. If this unit will not be included in snapshots. Defaults to - for device and - snapshot units, + for device and + snapshot units, for the others. @@ -609,46 +766,103 @@ ConditionPathExists= ConditionPathExistsGlob= ConditionPathIsDirectory= + ConditionPathIsSymbolicLink= + ConditionPathIsMountPoint= + ConditionPathIsReadWrite= ConditionDirectoryNotEmpty= + ConditionFileNotEmpty= + ConditionFileIsExecutable= ConditionKernelCommandLine= ConditionVirtualization= ConditionSecurity= + ConditionCapability= + ConditionHost= ConditionNull= Before starting a unit verify that the specified condition is - true. With + true. If it is not true the starting + of the unit will be skipped, however + all ordering dependencies of it are + still respected. A failing condition + will not result in the unit being + moved into a failure state. The + condition is checked at the time the + queued start job is to be + executed. + + With ConditionPathExists= - a file existence condition can be + a file existence condition is checked before a unit is started. If the specified absolute path name does - not exist startup of a unit will not - actually happen, however the unit is - still useful for ordering purposes in - this case. The condition is checked at - the time the queued start job is to be - executed. If the absolute path name - passed to + not exist the condition will + fail. If the absolute path name passed + to ConditionPathExists= is prefixed with an exclamation mark - (!), the test is negated, and the unit - only started if the path does not - exist. ConditionPathExistsGlob= - work in a similar way, but checks for - the existance of at least one file or - directory matching the specified - globbing - pattern. ConditionPathIsDirectory= + ('!'), the test is negated, and the unit + is only started if the path does not + exist. + + ConditionPathExistsGlob= + is similar to + ConditionPathExists=, + but checks for the existence of at + least one file or directory matching + the specified globbing pattern. + + ConditionPathIsDirectory= is similar to ConditionPathExists= but verifies whether a certain path - exists and is a directory. - ConditionDirectoryNotEmpty= + exists and is a + directory. + + ConditionPathIsSymbolicLink= + is similar to + ConditionPathExists= + but verifies whether a certain path + exists and is a symbolic + link. + + ConditionPathIsMountPoint= + is similar to + ConditionPathExists= + but verifies whether a certain path + exists and is a mount + point. + + ConditionPathIsReadWrite= + is similar to + ConditionPathExists= + but verifies whether the underlying + file system is readable and writable + (i.e. not mounted + read-only). + + ConditionDirectoryNotEmpty= is similar to ConditionPathExists= but verifies whether a certain path exists and is a non-empty - directory. Similarly + directory. + + ConditionFileNotEmpty= + is similar to + ConditionPathExists= + but verifies whether a certain path + exists and refers to a regular file + with a non-zero size. + + ConditionFileIsExecutable= + is similar to + ConditionPathExists= + but verifies whether a certain path + exists, is a regular file and marked + executable. + + Similar, ConditionKernelCommandLine= may be used to check whether a specific kernel command line option is @@ -656,46 +870,92 @@ exclamation mark unset). The argument must either be a single word, or an assignment (i.e. two words, separated - by the equality sign). In the former + '='). In the former case the kernel command line is searched for the word appearing as is, or as left hand side of an assignment. In the latter case the exact assignment is looked for with right and left hand side - matching. ConditionVirtualization= + matching. + + ConditionVirtualization= may be used to check whether the system is executed in a virtualized environment and optionally test whether it is a specific implementation. Takes either boolean value to check if being executed in - any virtual environment or one of the + any virtualized environment, or one of + vm and + container to test + against a generic type of + virtualization solution, or one of qemu, kvm, vmware, microsoft, oracle, xen, - pidns, - openvz to test - against a specific implementation. The + bochs, + chroot, + openvz, + lxc, + lxc-libvirt, + systemd-nspawn to + test against a specific + implementation. If multiple + virtualization technologies are nested + only the innermost is considered. The test may be negated by prepending an - exclamation mark. - ConditionSecurity= + exclamation mark. + + ConditionSecurity= may be used to check whether the given security module is enabled on the system. Currently the only recognized value is selinux. The test may be negated by prepending - an exclamation mark. Finally, + an exclamation + mark. + + ConditionCapability= + may be used to check whether the given + capability exists in the capability + bounding set of the service manager + (i.e. this does not check whether + capability is actually available in + the permitted or effective sets, see + capabilities7 + for details). Pass a capability name + such as CAP_MKNOD, + possibly prefixed with an exclamation + mark to negate the check. + + ConditionHost= + may be used to match against the + host name or machine ID of the + host. This either takes a host name + string (optionally with shell style + globs) which is tested against the + locally set host name as returned by + gethostname2, + or a machine ID formatted as string + (see + machine-id5). + The test may be negated by prepending + an exclamation mark. + + Finally, ConditionNull= may be used to add a constant condition check value to the unit. It takes a boolean argument. If set to false the condition will always fail, otherwise - succeed. If multiple conditions are + succeed. + + If multiple conditions are specified the unit will be executed if all of them apply (i.e. a logical AND is applied). Condition checks can be @@ -710,36 +970,23 @@ prefix an argument with the pipe symbol and an exclamation mark the pipe symbol must be passed first, the - exclamation second. + exclamation second. Except for + ConditionPathIsSymbolicLink=, + all path checks follow + symlinks. - Names= - - Additional names for - this unit. The names listed here must - have the same suffix (i.e. type) as - the unit file name. This option may be - specified more than once, in which - case all listed names are used. Note - that this option is different from the - Alias= option from - the [Install] section mentioned - below. See below for details. Note - that in almost all cases this option - is not what you want. A symlink alias - in the file system is generally - preferable since it can be used as - lookup key. If a unit with a symlinked - alias name is not loaded and needs to - be it is easily found via the - symlink. However, if a unit with an - alias name configured with this - setting is not loaded it will not be - discovered. This settings' only use is - in conjunction with service - instances. - + SourcePath= + A path to a + configuration file this unit has been + generated from. This is primarily + useful for implementation of generator + tools that convert configuration from + an external configuration file format + into native unit files. Thus + functionality should not be used in + normal units. @@ -767,37 +1014,16 @@ time, systemctl enable will create symlinks from these names - to the unit file name. Note that this - is different from the - Names= option from - the [Unit] section mentioned above: - The names from - Names= apply - unconditionally if the unit is - loaded. The names from - Alias= apply only - if the unit has actually been - installed with the - systemctl enable - command. Also, if systemd searches for a - unit, it will discover symlinked alias - names as configured with - Alias=, but not - names configured with - Names= only. It is - a common pattern to list a name in - both options. In this case, a unit - will be active under all names if - installed, but also if not installed - but requested explicitly under its - main name. + to the unit file name. WantedBy= + RequiredBy= Installs a symlink in the .wants/ + resp. .requires/ subdirectory for a unit. This has the effect that when the listed unit name is activated the unit listing it is @@ -842,7 +1068,8 @@ systemd.target5, systemd.path5, systemd.timer5, - systemd.snapshot5 + systemd.snapshot5, + capabilities7