with the <command>enable</command> command of the
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
tool which reads information from the [Install]
- section of unit files. (See below.)</para>
+ section of unit files. (See below.) A similar
+ functionality exists for <varname>Requires=</varname>
+ type dependencies as well, the directory suffix is
+ <filename>.requires/</filename> in this case.</para>
<para>Note that while systemd offers a flexible
dependency system between units it is recommended to
dependent on the type of unit:</para>
<variablelist>
- <varlistentry>
- <term><varname>Names=</varname></term>
-
- <listitem><para>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
- <varname>Alias=</varname> option from
- the [Install] section mentioned
- below. See below for details.</para>
- </listitem>
- </varlistentry>
<varlistentry>
<term><varname>Description=</varname></term>
unexpectedly disappear if a service
terminates on its own choice, a device
is unplugged or a mount point
- unmounted with involvement of
+ unmounted without involvement of
systemd.</para></listitem>
</varlistentry>
state.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>OnFailureIsolate=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option> the
+ unit listed in
+ <varname>OnFailure=</varname> will be
+ enqueued in isolation mode, i.e. all
+ units that are not its dependency will
+ be stopped. If this is set only a
+ single unit may be listed in
+ <varname>OnFailure=</varname>. Defaults
+ to
+ <option>false</option>.</para></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>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>IgnoreOnSnapshot=</varname></term>
+
+ <listitem><para>Takes a boolean
+ argument. If <option>true</option>
+ this unit will not be included in
+ snapshots. Defaults to
+ <option>false</option> for device and
+ snapshot units, <option>true</option>
+ for the others.</para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>StopWhenUnneeded=</varname></term>
<varlistentry>
<term><varname>ConditionPathExists=</varname></term>
+ <term><varname>ConditionPathIsDirectory=</varname></term>
+ <term><varname>ConditionDirectoryNotEmpty=</varname></term>
<term><varname>ConditionKernelCommandLine=</varname></term>
+ <term><varname>ConditionVirtualization=</varname></term>
+ <term><varname>ConditionSecurity=</varname></term>
+ <term><varname>ConditionNull=</varname></term>
<listitem><para>Before starting a unit
verify that the specified condition is
is prefixed with an exclamation mark
(!), the test is negated, and the unit
only started if the path does not
- exist. Similarly
+ exist. <varname>ConditionPathIsDirectory=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a directory.
+ <varname>ConditionDirectoryNotEmpty=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path
+ exists and is a non-empty
+ directory. Similarly
<varname>ConditionKernelCommandLine=</varname>
may be used to check whether a
specific kernel command line option is
set (or if prefixed with the
exclamation mark unset). The argument
must either be a single word, or an
- assignment (i.e. two words, seperated
+ assignment (i.e. two words, separated
by the equality sign). In the former
- case the kernel command line is search
- 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. If multiple conditions
- are specified the unit will be
- executed iff at least one of them
- applies (i.e. a logical OR is
- applied).</para></listitem>
+ 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. <varname>ConditionVirtualization=</varname>
+ 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
+ <varname>qemu</varname>,
+ <varname>kvm</varname>,
+ <varname>vmware</varname>,
+ <varname>microsoft</varname>,
+ <varname>oracle</varname>,
+ <varname>xen</varname>,
+ <varname>pidns</varname>,
+ <varname>openvz</varname> to test
+ against a specific implementation. The
+ test may be negated by prepending an
+ exclamation mark.
+ <varname>ConditionSecurity=</varname>
+ may be used to check whether the given security
+ module is enabled on the system.
+ Currently the only recognized value is
+ <varname>selinux</varname>.
+ The test may be negated by prepending an
+ exclamation mark. Finally,
+ <varname>ConditionNull=</varname> may
+ be used to add a constant condition
+ check value to the unit. It takes a
+ boolean argument. If set to
+ <varname>false</varname> the condition
+ will always fail, otherwise
+ 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
+ prefixed with a pipe symbol (|) in
+ which case a condition becomes a
+ triggering condition. If at least one
+ triggering condition is defined for a
+ unit then the unit will be executed if
+ at least one of the triggering
+ conditions apply and all of the
+ non-triggering conditions. If you
+ prefix an argument with the pipe
+ symbol and an exclamation mark the
+ pipe symbol must be passed first, the
+ exclamation second.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>Names=</varname></term>
+
+ <listitem><para>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
+ <varname>Alias=</varname> 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.</para>
+ </listitem>
</varlistentry>
</variablelist>
~ianmdlvl / elogind.git / blobdiff