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<refentry id="systemd.unit"

xmlns:xi="http://www.w3.org/2001/XInclude">

<refentryinfo>

<title>systemd.unit</title>

<productname>systemd</productname>

</refentryinfo>

<refmeta>

<refentrytitle>systemd.unit</refentrytitle>

<manvolnum>5</manvolnum>

</refmeta>

<refnamediv>

<refname>systemd.unit</refname>

<refpurpose>Unit configuration</refpurpose>

</refnamediv>

<refsynopsisdiv>

<para><simplelist type="inline">

<member><filename><replaceable>service</replaceable>.service</filename></member>

<member><filename><replaceable>socket</replaceable>.socket</filename></member>

<member><filename><replaceable>device</replaceable>.device</filename></member>

<member><filename><replaceable>mount</replaceable>.mount</filename></member>

<member><filename><replaceable>automount</replaceable>.automount</filename></member>

<member><filename><replaceable>swap</replaceable>.swap</filename></member>

<member><filename><replaceable>target</replaceable>.target</filename></member>

<member><filename><replaceable>path</replaceable>.path</filename></member>

<member><filename><replaceable>timer</replaceable>.timer</filename></member>

<member><filename><replaceable>slice</replaceable>.slice</filename></member>

<member><filename><replaceable>scope</replaceable>.scope</filename></member>

</simplelist></para>

<refsect2>

<title>System Unit Search Path</title>

<para><simplelist>

<member><filename>/etc/systemd/system.control/*</filename></member>

<member><filename>/run/systemd/system.control/*</filename></member>

<member><filename>/run/systemd/transient/*</filename></member>

<member><filename>/run/systemd/generator.early/*</filename></member>

<member><filename>/etc/systemd/system/*</filename></member>

<member><filename>/etc/systemd/system.attached/*</filename></member>

<member><filename>/run/systemd/system/*</filename></member>

<member><filename>/run/systemd/system.attached/*</filename></member>

<member><filename>/run/systemd/generator/*</filename></member>

<member><filename index='false'>…</filename></member>

<member><filename>/usr/local/lib/systemd/system/*</filename></member>

<member><filename>/usr/lib/systemd/system/*</filename></member>

<member><filename>/run/systemd/generator.late/*</filename></member>

</simplelist></para>

</refsect2>

<refsect2>

<title>User Unit Search Path</title>

<para><simplelist>

<member><filename>~/.config/systemd/user.control/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/user.control/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/transient/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/generator.early/*</filename></member>

<member><filename>~/.config/systemd/user/*</filename></member>

<member><filename>$XDG_CONFIG_DIRS/systemd/user/*</filename></member>

<member><filename>/etc/systemd/user/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/user/*</filename></member>

<member><filename>/run/systemd/user/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/generator/*</filename></member>

<member><filename>$XDG_DATA_HOME/systemd/user/*</filename></member>

<member><filename>$XDG_DATA_DIRS/systemd/user/*</filename></member>

<member><filename index='false'>…</filename></member>

<member><filename>/usr/local/lib/systemd/user/*</filename></member>

<member><filename>/usr/lib/systemd/user/*</filename></member>

<member><filename>$XDG_RUNTIME_DIR/systemd/generator.late/*</filename></member>

</simplelist></para>

</refsect2>

</refsynopsisdiv>

<refsect1>

<title>Description</title>

<para>A unit file is a plain text ini-style file that encodes information about a service, a

socket, a device, a mount point, an automount point, a swap file or partition, a start-up

target, a watched file system path, a timer controlled and supervised by

<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, a

resource management slice or a group of externally created processes. See

<citerefentry><refentrytitle>systemd.syntax</refentrytitle><manvolnum>7</manvolnum></citerefentry>

for a general description of the syntax.</para>

<para>This man page lists the common configuration options of all

the unit types. These options need to be configured in the [Unit]

or [Install] sections of the unit files.</para>

<para>In addition to the generic [Unit] and [Install] sections

described here, each unit may have a type-specific section, e.g.

[Service] for a service unit. See the respective man pages for

more information:

<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,

<citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>.

</para>

<para>Unit files are loaded from a set of paths determined during compilation, described in the next

section.</para>

<para>Valid unit names consist of a "unit name prefix", and a suffix specifying the unit type which

begins with a dot. The "unit name prefix" must consist of one or more valid characters (ASCII letters,

digits, <literal>:</literal>, <literal>-</literal>, <literal>_</literal>, <literal>.</literal>, and

<literal>\</literal>). The total length of the unit name including the suffix must not exceed 255

characters. The unit type suffix must be one of <literal>.service</literal>, <literal>.socket</literal>,

<literal>.device</literal>, <literal>.mount</literal>, <literal>.automount</literal>,

<literal>.swap</literal>, <literal>.target</literal>, <literal>.path</literal>,

<literal>.timer</literal>, <literal>.slice</literal>, or <literal>.scope</literal>.</para>

<para>Unit names can be parameterized by a single argument called the "instance name". The unit is then

constructed based on a "template file" which serves as the definition of multiple services or other

units. A template unit must have a single <literal>@</literal> at the end of the unit name prefix (right

before the type suffix). The name of the full unit is formed by inserting the instance name between

<literal>@</literal> and the unit type suffix. In the unit file itself, the instance parameter may be

referred to using <literal>%i</literal> and other specifiers, see below.</para>

<para>Unit files may contain additional options on top of those listed here. If systemd encounters an

unknown option, it will write a warning log message but continue loading the unit. If an option or

section name is prefixed with <option>X-</option>, it is ignored completely by systemd. Options within an

ignored section do not need the prefix. Applications may use this to include additional information in

the unit files. To access those options, applications need to parse the unit files on their own.</para>

<para>Units can be aliased (have an alternative name), by creating a symlink from the new name to the

existing name in one of the unit search paths. For example, <filename>systemd-networkd.service</filename>

has the alias <filename>dbus-org.freedesktop.network1.service</filename>, created during installation as

a symlink, so when <command>systemd</command> is asked through D-Bus to load

<filename>dbus-org.freedesktop.network1.service</filename>, it'll load

<filename>systemd-networkd.service</filename>. As another example, <filename>default.target</filename> —

the default system target started at boot — is commonly aliased to either

<filename>multi-user.target</filename> or <filename>graphical.target</filename> to select what is started

by default. Alias names may be used in commands like <command>disable</command>,

<command>start</command>, <command>stop</command>, <command>status</command>, and similar, and in all

unit dependency directives, including <varname>Wants=</varname>, <varname>Requires=</varname>,

<varname>Before=</varname>, <varname>After=</varname>. Aliases cannot be used with the

<command>preset</command> command.</para>

<para>Aliases obey the following restrictions: a unit of a certain type (<literal>.service</literal>,

<literal>.socket</literal>, …) can only be aliased by a name with the same type suffix. A plain unit (not

a template or an instance), may only be aliased by a plain name. A template instance may only be aliased

by another template instance, and the instance part must be identical. A template may be aliased by

another template (in which case the alias applies to all instances of the template). As a special case, a

template instance (e.g. <literal>[email protected]</literal>) may be a symlink to different template

(e.g. <literal>[email protected]</literal>). In that case, just this specific instance is aliased,

while other instances of the template (e.g. <literal>[email protected]</literal>,

<literal>[email protected]</literal>) are not aliased. Those rules preserve the requirement that the

instance (if any) is always uniquely defined for a given unit and all its aliases. The target of alias

symlink must point to a valid unit file location, i.e. the symlink target name must match the symlink

source name as described, and the destination path must be in one of the unit search paths, see UNIT FILE

LOAD PATH section below for more details. Note that the target file might not exist, i.e. the symlink may

be dangling.</para>

<para>Unit files may specify aliases through the <varname>Alias=</varname> directive in the [Install]

section. When the unit is enabled, symlinks will be created for those names, and removed when the unit is

disabled. For example, <filename>reboot.target</filename> specifies

<varname>Alias=ctrl-alt-del.target</varname>, so when enabled, the symlink

<filename>/etc/systemd/system/ctrl-alt-del.target</filename> pointing to the

<filename>reboot.target</filename> file will be created, and when

<keycombo><keycap>Ctrl</keycap><keycap>Alt</keycap><keycap>Del</keycap></keycombo> is invoked,

<command>systemd</command> will look for <filename>ctrl-alt-del.target</filename>, follow the symlink to

<filename>reboot.target</filename>, and execute <filename>reboot.service</filename> as part of that target.

<command>systemd</command> does not look at the [Install] section at all during normal operation, so any

directives in that section only have an effect through the symlinks created during enablement.</para>

<para>Along with a unit file <filename>foo.service</filename>, the directory

<filename>foo.service.wants/</filename> may exist. All unit files symlinked from such a directory are

implicitly added as dependencies of type <varname>Wants=</varname> to the unit. Similar functionality

exists for <varname>Requires=</varname> type dependencies as well, the directory suffix is

<filename>.requires/</filename> in this case. This functionality is useful to hook units into the

start-up of other units, without having to modify their unit files. For details about the semantics of

<varname>Wants=</varname> and <varname>Requires=</varname>, see below. The preferred way to create

symlinks in the <filename>.wants/</filename> or <filename>.requires/</filename> directories is by

specifying the dependency in [Install] section of the target unit, and creating the symlink in the file

system with the <command>enable</command> or <command>preset</command> commands of

<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The

target can be a normal unit (either plain or a specific instance of a template unit). In case when the

source unit is a template, the target can also be a template, in which case the instance will be

"propagated" to the target unit to form a valid unit instance. The target of symlinks in

<filename>.wants/</filename> or <filename>.requires/</filename> must thus point to a valid unit file

location, i.e. the symlink target name must satisfy the described requirements, and the destination path

must be in one of the unit search paths, see UNIT FILE LOAD PATH section below for more details. Note

that the target file might not exist, i.e. the symlink may be dangling.</para>

<para>Along with a unit file <filename>foo.service</filename>, a "drop-in" directory

<filename>foo.service.d/</filename> may exist. All files with the suffix

<literal>.conf</literal> from this directory will be merged in the alphanumeric order and parsed

after the main unit file itself has been parsed. This is useful to alter or add configuration

settings for a unit, without having to modify unit files. Each drop-in file must contain appropriate

section headers. For instantiated units, this logic will first look for the instance

<literal>.d/</literal> subdirectory (e.g. <literal>[email protected]/</literal>) and read its

<literal>.conf</literal> files, followed by the template <literal>.d/</literal> subdirectory (e.g.

<literal>[email protected]/</literal>) and the <literal>.conf</literal> files there. Moreover, for unit

names containing dashes (<literal>-</literal>), the set of directories generated by repeatedly

truncating the unit name after all dashes is searched too. Specifically, for a unit name

<filename>foo-bar-baz.service</filename> not only the regular drop-in directory

<filename>foo-bar-baz.service.d/</filename> is searched but also both <filename>foo-bar-.service.d/</filename> and

<filename>foo-.service.d/</filename>. This is useful for defining common drop-ins for a set of related units, whose

names begin with a common prefix. This scheme is particularly useful for mount, automount and slice units, whose

systematic naming structure is built around dashes as component separators. Note that equally named drop-in files

further down the prefix hierarchy override those further up,

i.e. <filename>foo-bar-.service.d/10-override.conf</filename> overrides

<filename>foo-.service.d/10-override.conf</filename>.</para>

<para>In cases of unit aliases (described above), dropins for the aliased name and all aliases are

loaded. In the example of <filename>default.target</filename> aliasing

<filename>graphical.target</filename>, <filename>default.target.d/</filename>,

<filename>default.target.wants/</filename>, <filename>default.target.requires/</filename>,

<filename>graphical.target.d/</filename>, <filename>graphical.target.wants/</filename>,

<filename>graphical.target.requires/</filename> would all be read. For templates, dropins for the

template, any template aliases, the template instance, and all alias instances are read. When just a

specific template instance is aliased, then the dropins for the target template, the target template

instance, and the alias template instance are read.</para>

<para>In addition to <filename>/etc/systemd/system</filename>, the drop-in <literal>.d/</literal>

directories for system services can be placed in <filename>/usr/lib/systemd/system</filename> or

<filename>/run/systemd/system</filename> directories. Drop-in files in <filename>/etc/</filename>

take precedence over those in <filename>/run/</filename> which in turn take precedence over those

in <filename>/usr/lib/</filename>. Drop-in files under any of these directories take precedence

over unit files wherever located. Multiple drop-in files with different names are applied in

lexicographic order, regardless of which of the directories they reside in.</para>

<para>Units also support a top-level drop-in with <filename><replaceable>type</replaceable>.d/</filename>,

where <replaceable>type</replaceable> may be e.g. <literal>service</literal> or <literal>socket</literal>,

that allows altering or adding to the settings of all corresponding unit files on the system.

The formatting and precedence of applying drop-in configurations follow what is defined above.

Files in <filename><replaceable>type</replaceable>.d/</filename> have lower precedence compared

to files in name-specific override directories. The usual rules apply: multiple drop-in files

with different names are applied in lexicographic order, regardless of which of the directories

they reside in, so a file in <filename><replaceable>type</replaceable>.d/</filename> applies

to a unit only if there are no drop-ins or masks with that name in directories with higher

precedence. See Examples.</para>

<para>Note that while systemd offers a flexible dependency system

between units it is recommended to use this functionality only

sparingly and instead rely on techniques such as bus-based or

socket-based activation which make dependencies implicit,

resulting in a both simpler and more flexible system.</para>

<para>As mentioned above, a unit may be instantiated from a template file. This allows creation

of multiple units from a single configuration file. If systemd looks for a unit configuration

file, it will first search for the literal unit name in the file system. If that yields no

success and the unit name contains an <literal>@</literal> character, systemd will look for a

unit template that shares the same name but with the instance string (i.e. the part between the

<literal>@</literal> character and the suffix) removed. Example: if a service

<filename>[email protected]</filename> is requested and no file by that name is found, systemd

will look for <filename>[email protected]</filename> and instantiate a service from that

configuration file if it is found.</para>

<para>To refer to the instance string from within the

configuration file you may use the special <literal>%i</literal>

specifier in many of the configuration options. See below for

details.</para>

<para>If a unit file is empty (i.e. has the file size 0) or is

symlinked to <filename>/dev/null</filename>, its configuration

will not be loaded and it appears with a load state of

<literal>masked</literal>, and cannot be activated. Use this as an

effective way to fully disable a unit, making it impossible to

start it even manually.</para>

<para>Files (including directories) with names that match certain patterns are

generally ignored. This includes names that start with a <literal>.</literal> or

end with a <literal>.ignore</literal>.</para>

<para>The unit file format is covered by the

<ulink url="https://systemd.io/PORTABILITY_AND_STABILITY/">Interface

Portability and Stability Promise</ulink>.</para>

</refsect1>

<refsect1>

<title>String Escaping for Inclusion in Unit Names</title>

<para>Sometimes it is useful to convert arbitrary strings into unit names. To facilitate this, a method of string

escaping is used, in order to map strings containing arbitrary byte values (except <constant>NUL</constant>) into

valid unit names and their restricted character set. A common special case are unit names that reflect paths to

objects in the file system hierarchy. Example: a device unit <filename>dev-sda.device</filename> refers to a device

with the device node <filename index="false">/dev/sda</filename> in the file system.</para>

<para>The escaping algorithm operates as follows: given a string, any <literal>/</literal> character is

replaced by <literal>-</literal>, and all other characters which are not ASCII alphanumerics,

<literal>:</literal>, <literal>_</literal> or <literal>.</literal> are replaced by C-style

<literal>\x2d</literal> escapes. In addition, <literal>.</literal> is replaced with such a C-style escape

when it would appear as the first character in the escaped string.</para>

<para>When the input qualifies as absolute file system path, this algorithm is extended slightly: the path to the

root directory <literal>/</literal> is encoded as single dash <literal>-</literal>. In addition, any leading,

trailing or duplicate <literal>/</literal> characters are removed from the string before transformation. Example:

<filename index="false">/foo//bar/baz/</filename> becomes <literal>foo-bar-baz</literal>.</para>

<para>This escaping is fully reversible, as long as it is known whether the escaped string was a path (the

unescaping results are different for paths and non-path strings). The

<citerefentry><refentrytitle>systemd-escape</refentrytitle><manvolnum>1</manvolnum></citerefentry> command may be

used to apply and reverse escaping on arbitrary strings. Use <command>systemd-escape --path</command> to escape

path strings, and <command>systemd-escape</command> without <option>--path</option> otherwise.</para>

</refsect1>

<refsect1>

<title>Automatic dependencies</title>

<refsect2>

<title>Implicit Dependencies</title>

<para>A number of unit dependencies are implicitly established, depending on unit type and

unit configuration. These implicit dependencies can make unit configuration file cleaner. For

the implicit dependencies in each unit type, please refer to section "Implicit Dependencies"

in respective man pages.</para>

<para>For example, service units with <varname>Type=dbus</varname> automatically acquire

dependencies of type <varname>Requires=</varname> and <varname>After=</varname> on

<filename>dbus.socket</filename>. See

<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>

for details.</para>

</refsect2>

<refsect2>

<title>Default Dependencies</title>

<para>Default dependencies are similar to implicit dependencies, but can be turned on and off

by setting <varname>DefaultDependencies=</varname> to <varname>yes</varname> (the default) and

<varname>no</varname>, while implicit dependencies are always in effect. See section "Default

Dependencies" in respective man pages for the effect of enabling

<varname>DefaultDependencies=</varname> in each unit types.</para>

<para>For example, target units will complement all configured dependencies of type

<varname>Wants=</varname> or <varname>Requires=</varname> with dependencies of type

<varname>After=</varname>. See

<citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>

for details. Note that this behavior can be opted out by setting

<varname>DefaultDependencies=no</varname> in the specified units, or it can be selectively

overridden via an explicit <varname>Before=</varname> dependency.</para>

</refsect2>

</refsect1>

<refsect1>

<title>Unit File Load Path</title>

<para>Unit files are loaded from a set of paths determined during

compilation, described in the two tables below. Unit files found

in directories listed earlier override files with the same name in

directories lower in the list

<xi:include href="standard-conf.xml" xpointer="usr-local-footnote" />.

</para>

<para>When the variable <varname>$SYSTEMD_UNIT_PATH</varname> is set,

the contents of this variable overrides the unit load path. If

<varname>$SYSTEMD_UNIT_PATH</varname> ends with an empty component

(<literal>:</literal>), the usual unit load path will be appended

to the contents of the variable.</para>

<table>

<title>

Load path when running in system mode (<option>--system</option>).

</title>

<tgroup cols='2'>

<colspec colname='path' />

<colspec colname='expl' />

<thead>

<row>

<entry>Path</entry>

<entry>Description</entry>

</row>

</thead>

<tbody>

<row>

<entry><filename>/etc/systemd/system.control</filename></entry>

<entry morerows="1">Persistent and transient configuration created using the dbus API</entry>

</row>

<row>

<entry><filename>/run/systemd/system.control</filename></entry>

</row>

<row>

<entry><filename>/run/systemd/transient</filename></entry>

<entry>Dynamic configuration for transient units</entry>

</row>

<row>

<entry><filename>/run/systemd/generator.early</filename></entry>

<entry>Generated units with high priority (see <replaceable>early-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

<row>

<entry><filename>/etc/systemd/system</filename></entry>

<entry>System units created by the administrator</entry>

</row>

<row>

<entry><filename>/run/systemd/system</filename></entry>

<entry>Runtime units</entry>

</row>

<row>

<entry><filename>/run/systemd/generator</filename></entry>

<entry>Generated units with medium priority (see <replaceable>normal-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

<row>

<entry><filename>/usr/local/lib/systemd/system</filename></entry>

<entry>System units installed by the administrator</entry>

</row>

<row>

<entry><filename>/usr/lib/systemd/system</filename></entry>

<entry>System units installed by the distribution package manager</entry>

</row>

<row>

<entry><filename>/run/systemd/generator.late</filename></entry>

<entry>Generated units with low priority (see <replaceable>late-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

</tbody>

</tgroup>

</table>

<table>

<title>

Load path when running in user mode (<option>--user</option>).

</title>

<tgroup cols='2'>

<colspec colname='path' />

<colspec colname='expl' />

<thead>

<row>

<entry>Path</entry>

<entry>Description</entry>

</row>

</thead>

<tbody>

<row>

<entry><filename>$XDG_CONFIG_HOME/systemd/user.control</filename> or <filename

>~/.config/systemd/user.control</filename></entry>

<entry morerows="1">Persistent and transient configuration created using the dbus API (<varname>$XDG_CONFIG_HOME</varname> is used if set, <filename>~/.config</filename> otherwise)</entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/user.control</filename></entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/transient</filename></entry>

<entry>Dynamic configuration for transient units</entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/generator.early</filename></entry>

<entry>Generated units with high priority (see <replaceable>early-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

<row>

<entry><filename>$XDG_CONFIG_HOME/systemd/user</filename> or <filename>$HOME/.config/systemd/user</filename></entry>

<entry>User configuration (<varname>$XDG_CONFIG_HOME</varname> is used if set, <filename>~/.config</filename> otherwise)</entry>

</row>

<row>

<entry><filename>$XDG_CONFIG_DIRS/systemd/user</filename> or <filename>/etc/xdg/systemd/user</filename></entry>

<entry>Additional configuration directories as specified by the XDG base directory specification (<varname>$XDG_CONFIG_DIRS</varname> is used if set, <filename>/etc/xdg</filename> otherwise)</entry>

</row>

<row>

<entry><filename>/etc/systemd/user</filename></entry>

<entry>User units created by the administrator</entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/user</filename></entry>

<entry>Runtime units (only used when $XDG_RUNTIME_DIR is set)</entry>

</row>

<row>

<entry><filename>/run/systemd/user</filename></entry>

<entry>Runtime units</entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/generator</filename></entry>

<entry>Generated units with medium priority (see <replaceable>normal-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

<row>

<entry><filename>$XDG_DATA_HOME/systemd/user</filename> or <filename>$HOME/.local/share/systemd/user</filename></entry>

<entry>Units of packages that have been installed in the home directory (<varname>$XDG_DATA_HOME</varname> is used if set, <filename>~/.local/share</filename> otherwise)</entry>

</row>

<row>

<entry><filename>$XDG_DATA_DIRS/systemd/user</filename> or <filename>/usr/local/share/systemd/user</filename> and <filename>/usr/share/systemd/user</filename></entry>

<entry>Additional data directories as specified by the XDG base directory specification (<varname>$XDG_DATA_DIRS</varname> is used if set, <filename>/usr/local/share</filename> and <filename>/usr/share</filename> otherwise)</entry>

</row>

<row>

<entry><filename>$dir/systemd/user</filename> for each <varname index="false">$dir</varname> in <varname>$XDG_DATA_DIRS</varname></entry>

<entry>Additional locations for installed user units, one for each entry in <varname>$XDG_DATA_DIRS</varname></entry>

</row>

<row>

<entry><filename>/usr/local/lib/systemd/user</filename></entry>

<entry>User units installed by the administrator</entry>

</row>

<row>

<entry><filename>/usr/lib/systemd/user</filename></entry>

<entry>User units installed by the distribution package manager</entry>

</row>

<row>

<entry><filename>$XDG_RUNTIME_DIR/systemd/generator.late</filename></entry>

<entry>Generated units with low priority (see <replaceable>late-dir</replaceable> in <citerefentry

><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>)</entry>

</row>

</tbody>

</tgroup>

</table>

<para>The set of load paths for the user manager instance may be augmented or

changed using various environment variables. And environment variables may in

turn be set using environment generators, see

<citerefentry><refentrytitle>systemd.environment-generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.

In particular, <varname>$XDG_DATA_HOME</varname> and

<varname>$XDG_DATA_DIRS</varname> may be easily set using

<citerefentry><refentrytitle>systemd-environment-d-generator</refentrytitle><manvolnum>8</manvolnum></citerefentry>.

Thus, directories listed here are just the defaults. To see the actual list that

would be used based on compilation options and current environment use

<programlisting>systemd-analyze --user unit-paths</programlisting>

</para>

<para>Moreover, additional units might be loaded into systemd from directories not on the unit load path

by creating a symlink pointing to a unit file in the directories. You can use <command>systemctl

link</command> for this; see

<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The file

system where the linked unit files are located must be accessible when systemd is started (e.g. anything

underneath <filename>/home/</filename> or <filename>/var/</filename> is not allowed, unless those

directories are located on the root file system).</para>

<para>It is important to distinguish "linked unit files" from "unit file aliases": any symlink where the

symlink <emphasis>target</emphasis> is within the unit load path becomes an alias: the source name and

the target file name must satisfy specific constraints listed above in the discussion of aliases, but the

symlink target does not have to exist, and in fact the symlink target path is not used, except to check

whether the target is within the unit load path. In contrast, a symlink which goes outside of the unit

load path signifies a linked unit file. The symlink is followed when loading the file, but the

destination name is otherwise unused (and may even not be a valid unit file name). For example, symlinks

<filename index='false'>/etc/systemd/system/alias1.service</filename> → <filename index='false'>service1.service</filename>,

<filename index='false'>/etc/systemd/system/alias2.service</filename> → <filename index='false'>/usr/lib/systemd/service1.service</filename>,

<filename index='false'>/etc/systemd/system/alias3.service</filename> → <filename index='false'>/etc/systemd/system/service1.service</filename>

are all valid aliases and <filename index='false'>service1.service</filename> will have

four names, even if the unit file is located at

<filename index='false'>/run/systemd/system/service1.service</filename>. In contrast,

a symlink <filename index='false'>/etc/systemd/system/link1.service</filename> → <filename index='false'>../link1_service_file</filename>

means that <filename index='false'>link1.service</filename> is a "linked unit" and the contents of

<filename index='false'>/etc/systemd/link1_service_file</filename> provide its configuration.</para>

</refsect1>

<refsect1>

<title>Unit Garbage Collection</title>

<para>The system and service manager loads a unit's configuration automatically when a unit is referenced for the

first time. It will automatically unload the unit configuration and state again when the unit is not needed anymore

("garbage collection"). A unit may be referenced through a number of different mechanisms:</para>

<orderedlist>

<listitem><para>Another loaded unit references it with a dependency such as <varname>After=</varname>,

<varname>Wants=</varname>, …</para></listitem>

<listitem><para>The unit is currently starting, running, reloading or stopping.</para></listitem>

<listitem><para>The unit is currently in the <constant>failed</constant> state. (But see below.)</para></listitem>

<listitem><para>A job for the unit is pending.</para></listitem>

<listitem><para>The unit is pinned by an active IPC client program.</para></listitem>

<listitem><para>The unit is a special "perpetual" unit that is always active and loaded. Examples for perpetual

units are the root mount unit <filename>-.mount</filename> or the scope unit <filename>init.scope</filename> that

the service manager itself lives in.</para></listitem>

<listitem><para>The unit has running processes associated with it.</para></listitem>

</orderedlist>

<para>The garbage collection logic may be altered with the <varname>CollectMode=</varname> option, which allows

configuration whether automatic unloading of units that are in <constant>failed</constant> state is permissible,

see below.</para>

<para>Note that when a unit's configuration and state is unloaded, all execution results, such as exit codes, exit

signals, resource consumption and other statistics are lost, except for what is stored in the log subsystem.</para>

<para>Use <command>systemctl daemon-reload</command> or an equivalent command to reload unit configuration while

the unit is already loaded. In this case, all configuration settings are flushed out and replaced with the new

configuration (which however might not be in effect immediately), however all runtime state is

saved/restored.</para>

</refsect1>

<refsect1>

<title>[Unit] Section Options</title>

<para>The unit file may include a [Unit] section, which carries

generic information about the unit that is not dependent on the

type of unit:</para>

<variablelist class='unit-directives'>

<varlistentry>

<term><varname>Description=</varname></term>

<listitem><para>A brief, meaningful, human-readable text identifying the unit. This may be used by

<command>systemd</command> (and suitable UIs) as a user-visible label for the unit, so this string

should identify the unit rather than just describe it, despite the name. This string also should not

just repeat the unit name. <literal>Apache HTTP Server</literal> or <literal>Postfix Mail

Server</literal> are good examples. Bad examples are <literal>high-performance lightweight HTTP

server</literal> (too generic) or <literal>Apache</literal> (meaningless for people who do not know

the Apache HTTP server project, duplicates the unit name). <command>systemd</command> may use this

string as a noun in status messages (<literal>Starting

<replaceable>Description</replaceable>...</literal>, <literal>Started

<replaceable>Description</replaceable>.</literal>, <literal>Reached target

<replaceable>Description</replaceable>.</literal>, <literal>Failed to start

<replaceable>Description</replaceable>.</literal>), so it should be capitalized, and should not be a

full sentence, or a phrase with a verb conjugated in the present continuous, or end in a full

stop. Bad examples include <literal>exiting the container</literal>, <literal>updating the database

once per day.</literal>, or <literal>OpenSSH server second instance daemon</literal>.</para>

<xi:include href="version-info.xml" xpointer="v201"/>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>Documentation=</varname></term>

<listitem><para>A space-separated list of URIs referencing

documentation for this unit or its configuration. Accepted are

only URIs of the types <literal>http://</literal>,

<literal>https://</literal>, <literal>file:</literal>,

<literal>info:</literal>, <literal>man:</literal>. For more

information about the syntax of these URIs, see <citerefentry

project='man-pages'><refentrytitle>uri</refentrytitle><manvolnum>7</manvolnum></citerefentry>.

The URIs should be listed in order of relevance, starting with

the most relevant. It is a good idea to first reference

documentation that explains what the unit's purpose is,

followed by how it is configured, followed by any other

related documentation. This option may be specified more than

once, in which case the specified list of URIs is merged. If

the empty string is assigned to this option, the list is reset

and all prior assignments will have no

effect.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>Wants=</varname></term>

<listitem><para>Configures (weak) requirement dependencies on other units. This option may be

specified more than once or multiple space-separated units may be specified in one option in which

case dependencies for all listed names will be created. Dependencies of this type may also be

configured outside of the unit configuration file by adding a symlink to a

<filename>.wants/</filename> directory accompanying the unit file. For details, see above.</para>

<para>Units listed in this option will be started if the configuring unit is. However, if the listed

units fail to start or cannot be added to the transaction, this has no impact on the validity of the

transaction as a whole, and this unit will still be started. This is the recommended way to hook

the start-up of one unit to the start-up of another unit.</para>

<para>Note that requirement dependencies do not influence the order in which services are started or

stopped. This has to be configured independently with the <varname>After=</varname> or

<varname>Before=</varname> options. If unit <filename>foo.service</filename> pulls in unit

<filename>bar.service</filename> as configured with <varname>Wants=</varname> and no ordering is

configured with <varname>After=</varname> or <varname>Before=</varname>, then both units will be

started simultaneously and without any delay between them if <filename>foo.service</filename> is

activated.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>Requires=</varname></term>

<listitem><para>Similar to <varname>Wants=</varname>, but declares a stronger requirement

dependency. Dependencies of this type may also be configured by adding a symlink to a

<filename>.requires/</filename> directory accompanying the unit file.</para>

<para>If this unit gets activated, the units listed will be activated as well. If one of

the other units fails to activate, and an ordering dependency <varname>After=</varname> on the

failing unit is set, this unit will not be started. Besides, with or without specifying

<varname>After=</varname>, this unit will be stopped (or restarted) if one of the other units is

explicitly stopped (or restarted).</para>

<para>Often, it is a better choice to use <varname>Wants=</varname> instead of

<varname>Requires=</varname> in order to achieve a system that is more robust when dealing with

failing services.</para>

<para>Note that this dependency type does not imply that the other unit always has to be in active state when

this unit is running. Specifically: failing condition checks (such as <varname>ConditionPathExists=</varname>,

<varname>ConditionPathIsSymbolicLink=</varname>, … — see below) do not cause the start job of a unit with a

<varname>Requires=</varname> dependency on it to fail. Also, some unit types may deactivate on their own (for

example, a service process may decide to exit cleanly, or a device may be unplugged by the user), which is not

propagated to units having a <varname>Requires=</varname> dependency. Use the <varname>BindsTo=</varname>

dependency type together with <varname>After=</varname> to ensure that a unit may never be in active state

without a specific other unit also in active state (see below).</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>Requisite=</varname></term>

<listitem><para>Similar to <varname>Requires=</varname>. However, if the units listed here

are not started already, they will not be started and the starting of this unit will fail

immediately. <varname>Requisite=</varname> does not imply an ordering dependency, even if

both units are started in the same transaction. Hence this setting should usually be

combined with <varname>After=</varname>, to ensure this unit is not started before the other

unit.</para>

<para>When <varname>Requisite=b.service</varname> is used on

<filename>a.service</filename>, this dependency will show as

<varname>RequisiteOf=a.service</varname> in property listing of

<filename>b.service</filename>. <varname>RequisiteOf=</varname>

dependency cannot be specified directly.</para>

<xi:include href="version-info.xml" xpointer="v201"/>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>BindsTo=</varname></term>

<listitem><para>Configures requirement dependencies, very similar in style to

<varname>Requires=</varname>. However, this dependency type is stronger: in addition to the effects of

<varname>Requires=</varname>, which already stops (or restarts) the configuring unit when a listed unit is

explicitly stopped (or restarted), it also does so when a listed unit stops unexpectedly (which includes when it

fails).

Units can suddenly, unexpectedly enter inactive state for different reasons: the main process of a service unit

might terminate on its own choice, the backing device of a device unit might be unplugged or the mount point of

a mount unit might be unmounted without involvement of the system and service manager.</para>

<para>When used in conjunction with <varname>After=</varname> on the same unit the behaviour of

<varname>BindsTo=</varname> is even stronger. In this case, the unit bound to strictly has to be in active

state for this unit to also be in active state. This not only means a unit bound to another unit that suddenly

enters inactive state, but also one that is bound to another unit that gets skipped due to an unmet condition

check (such as <varname>ConditionPathExists=</varname>, <varname>ConditionPathIsSymbolicLink=</varname>, … —

see below) will be stopped, should it be running. Hence, in many cases it is best to combine

<varname>BindsTo=</varname> with <varname>After=</varname>.</para>

<para>When <varname>BindsTo=b.service</varname> is used on

<filename>a.service</filename>, this dependency will show as

<varname>BoundBy=a.service</varname> in property listing of

<filename>b.service</filename>. <varname>BoundBy=</varname>

dependency cannot be specified directly.</para>

<xi:include href="version-info.xml" xpointer="v201"/>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>PartOf=</varname></term>

<listitem><para>Configures dependencies similar to

<varname>Requires=</varname>, 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.</para>

<para>When <varname>PartOf=b.service</varname> is used on

<filename>a.service</filename>, this dependency will show as

<varname>ConsistsOf=a.service</varname> in property listing of

<filename>b.service</filename>. <varname>ConsistsOf=</varname>

dependency cannot be specified directly.</para>

<xi:include href="version-info.xml" xpointer="v201"/>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>Upholds=</varname></term>

<listitem><para>Configures dependencies similar to <varname>Wants=</varname>, but as long as this unit

is up, all units listed in <varname>Upholds=</varname> are started whenever found to be inactive or

failed, and no job is queued for them. While a <varname>Wants=</varname> dependency on another unit

has a one-time effect when this units started, a <varname>Upholds=</varname> dependency on it has a

continuous effect, constantly restarting the unit if necessary. This is an alternative to the

<varname>Restart=</varname> setting of service units, to ensure they are kept running whatever

happens. The restart happens without delay, and usual per-unit rate-limit applies.</para>

<para>When <varname>Upholds=b.service</varname> is used on <filename>a.service</filename>, this

dependency will show as <varname>UpheldBy=a.service</varname> in the property listing of

<filename>b.service</filename>.</para>

<xi:include href="version-info.xml" xpointer="v249"/>

</listitem>

</varlistentry>

<varlistentry>

<term><varname>Conflicts=</varname></term>

<listitem><para>A space-separated list of unit names. Configures negative requirement

dependencies. If a unit has a <varname>Conflicts=</varname> requirement on a set of other units,

then starting it will stop all of them and starting any of them will stop it.</para>

<para>Note that this setting does not imply an ordering dependency, similarly to the

<varname>Wants=</varname> and <varname>Requires=</varname> dependencies described above. This means

that to ensure that the conflicting unit is stopped before the other unit is started, an

<varname>After=</varname> or <varname>Before=</varname> dependency must be declared. It does not

matter which of the two ordering dependencies is used, because stop jobs are always ordered before

start jobs, see the discussion in <varname>Before=</varname>/<varname>After=</varname> below.</para>

<para>If unit A that conflicts with unit B is scheduled to

be started at the same time as B, the transaction will either

fail (in case both are required parts of the transaction) or be

modified to be fixed (in case one or both jobs are not a

required part of the transaction). In the latter case, the job

that is not required will be removed, or in case both are

not required, the unit that conflicts will be started and the

unit that is conflicted is stopped.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>Before=</varname></term>

<term><varname>After=</varname></term>

<listitem><para>These two settings expect a space-separated list of unit names. They may be specified

more than once, in which case dependencies for all listed names are created.</para>

<para>Those two settings configure ordering dependencies between units. If unit

<filename>foo.service</filename> contains the setting <option>Before=bar.service</option> and both

units are being started, <filename>bar.service</filename>'s start-up is delayed until

<filename>foo.service</filename> has finished starting up. <varname>After=</varname> is the inverse

of <varname>Before=</varname>, i.e. while <varname>Before=</varname> ensures that the configured unit

is started before the listed unit begins starting up, <varname>After=</varname> ensures the opposite,

that the listed unit is fully started up before the configured unit is started.</para>

<para>When two units with an ordering dependency between them are shut down, the inverse of the

start-up order is applied. I.e. if a unit is configured with <varname>After=</varname> on another

unit, the former is stopped before the latter if both are shut down. Given two units with any

ordering dependency between them, if one unit is shut down and the other is started up, the shutdown

is ordered before the start-up. It does not matter if the ordering dependency is

<varname>After=</varname> or <varname>Before=</varname>, in this case. It also does not matter which

of the two is shut down, as long as one is shut down and the other is started up; the shutdown is

ordered before the start-up in all cases. If two units have no ordering dependencies between them,

they are shut down or started up simultaneously, and no ordering takes place. It depends on the unit

type when precisely a unit has finished starting up. Most importantly, for service units start-up is

considered completed for the purpose of <varname>Before=</varname>/<varname>After=</varname> when all

its configured start-up commands have been invoked and they either failed or reported start-up

success. Note that this includes <varname>ExecStartPost=</varname> (or

<varname>ExecStopPost=</varname> for the shutdown case).</para>

<para>Note that those settings are independent of and orthogonal to the requirement dependencies as

configured by <varname>Requires=</varname>, <varname>Wants=</varname>, <varname>Requisite=</varname>,

or <varname>BindsTo=</varname>. It is a common pattern to include a unit name in both the

<varname>After=</varname> and <varname>Wants=</varname> options, in which case the unit listed will

be started before the unit that is configured with these options.</para>

<para>Note that <varname>Before=</varname> dependencies on device units have no effect and are not

supported. Devices generally become available as a result of an external hotplug event, and systemd

creates the corresponding device unit without delay.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>OnFailure=</varname></term>

<listitem><para>A space-separated list of one or more units that are activated when this unit enters

the <literal>failed</literal> state.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>OnSuccess=</varname></term>

<listitem><para>A space-separated list of one or more units that are activated when this unit enters

the <literal>inactive</literal> state.</para>

<xi:include href="version-info.xml" xpointer="v249"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>PropagatesReloadTo=</varname></term>

<term><varname>ReloadPropagatedFrom=</varname></term>

<listitem><para>A space-separated list of one or more units to which reload requests from this unit

shall be propagated to, or units from which reload requests shall be propagated to this unit,

respectively. Issuing a reload request on a unit will automatically also enqueue reload requests on

all units that are linked to it using these two settings.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>PropagatesStopTo=</varname></term>

<term><varname>StopPropagatedFrom=</varname></term>

<listitem><para>A space-separated list of one or more units to which stop requests from this unit

shall be propagated to, or units from which stop requests shall be propagated to this unit,

respectively. Issuing a stop request on a unit will automatically also enqueue stop requests on all

units that are linked to it using these two settings.</para>

<xi:include href="version-info.xml" xpointer="v249"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>JoinsNamespaceOf=</varname></term>

<listitem><para>For units that start processes (such as service units), lists one or more other units

whose network and/or temporary file namespace to join. If this is specified on a unit (say,

<filename>a.service</filename> has <varname>JoinsNamespaceOf=b.service</varname>), then the inverse

dependency (<varname>JoinsNamespaceOf=a.service</varname> for b.service) is implied. This only

applies to unit types which support the <varname>PrivateNetwork=</varname>,

<varname>NetworkNamespacePath=</varname>, <varname>PrivateIPC=</varname>,

<varname>IPCNamespacePath=</varname>, and <varname>PrivateTmp=</varname> directives (see

<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for

details). If a unit that has this setting set is started, its processes will see the same

<filename>/tmp/</filename>, <filename>/var/tmp/</filename>, IPC namespace and network namespace as

one listed unit that is started. If multiple listed units are already started and these do not share

their namespace, then it is not defined which namespace is joined. Note that this setting only has an

effect if <varname>PrivateNetwork=</varname>/<varname>NetworkNamespacePath=</varname>,

<varname>PrivateIPC=</varname>/<varname>IPCNamespacePath=</varname> and/or

<varname>PrivateTmp=</varname> is enabled for both the unit that joins the namespace and the unit

whose namespace is joined.</para>

<xi:include href="version-info.xml" xpointer="v209"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>RequiresMountsFor=</varname></term>

<listitem><para>Takes a space-separated list of absolute

paths. Automatically adds dependencies of type

<varname>Requires=</varname> and <varname>After=</varname> for

all mount units required to access the specified path.</para>

<para>Mount points marked with <option>noauto</option> are not

mounted automatically through <filename>local-fs.target</filename>,

but are still honored for the purposes of this option, i.e. they

will be pulled in by this unit.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>WantsMountsFor=</varname></term>

<listitem><para>Same as <varname>RequiresMountsFor=</varname>,

but adds dependencies of type <varname>Wants=</varname> instead

of <varname>Requires=</varname>.</para>

<xi:include href="version-info.xml" xpointer="v256"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>OnSuccessJobMode=</varname></term>

<term><varname>OnFailureJobMode=</varname></term>

<listitem><para>Takes a value of

<literal>fail</literal>,

<literal>replace</literal>,

<literal>replace-irreversibly</literal>,

<literal>isolate</literal>,

<literal>flush</literal>,

<literal>ignore-dependencies</literal> or

<literal>ignore-requirements</literal>.

<literal>OnFailureJobMode=</literal> defaults to

<literal>replace</literal>,

<literal>OnSuccessJobMode=</literal> defaults to

<literal>fail</literal>. Specifies how the units listed in

<varname>OnSuccess=</varname>/<varname>OnFailure=</varname> will be enqueued. See

<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s

<option>--job-mode=</option> option for details on the

possible values. If this is set to <literal>isolate</literal>,

only a single unit may be listed in

<varname>OnSuccess=</varname>/<varname>OnFailure=</varname>.</para>

<xi:include href="version-info.xml" xpointer="v209"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>IgnoreOnIsolate=</varname></term>

<listitem><para>Takes a boolean argument. If <option>true</option>, this unit will not be stopped

when isolating another unit. Defaults to <option>false</option> for service, target, socket, timer,

and path units, and <option>true</option> for slice, scope, device, swap, mount, and automount

units.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>

<varlistentry>

<term><varname>StopWhenUnneeded=</varname></term>

<listitem><para>Takes a boolean argument. If

<option>true</option>, this unit will be stopped when it is no

longer used. Note that, in order to minimize the work to be

executed, systemd will not stop units by default unless they

are conflicting with other units, or the user explicitly

requested their shut down. If this option is set, a unit will

be automatically cleaned up if no other active unit requires

it. Defaults to <option>false</option>.</para>

<xi:include href="version-info.xml" xpointer="v201"/></listitem>

</varlistentry>