diff options
Diffstat (limited to 'man/systemd.socket.xml')
| -rw-r--r-- | man/systemd.socket.xml | 92 |
1 files changed, 49 insertions, 43 deletions
diff --git a/man/systemd.socket.xml b/man/systemd.socket.xml index 1d20a8f7f7..68d01cccc5 100644 --- a/man/systemd.socket.xml +++ b/man/systemd.socket.xml @@ -97,16 +97,7 @@ <filename>foo@.service</filename> must exist from which services are instantiated for each incoming connection.</para> - <para>Unless <varname>DefaultDependencies=</varname> in the <literal>[Unit]</literal> section is set to - <option>false</option>, socket units will implicitly have dependencies of type <varname>Requires=</varname> and - <varname>After=</varname> on <filename>sysinit.target</filename> as well as dependencies of type - <varname>Conflicts=</varname> and <varname>Before=</varname> on <filename>shutdown.target</filename>. These ensure - that socket units pull in basic system initialization, and are terminated cleanly prior to system shutdown. Only - sockets involved with early boot or late system shutdown should disable this option.</para> - - <para>Socket units will have a <varname>Before=</varname> - dependency on the service which they trigger added implicitly. No - implicit <varname>WantedBy=</varname> or + <para>No implicit <varname>WantedBy=</varname> or <varname>RequiredBy=</varname> dependency from the socket to the service is added. This means that the service may be started without the socket, in which case it must be able to open sockets @@ -130,31 +121,24 @@ </refsect1> <refsect1> - <title>Automatic Dependencies</title> - - <para>Socket units automatically gain a <varname>Before=</varname> - dependency on the service units they activate.</para> - - <para>Socket units referring to file system paths (such as AF_UNIX - sockets or FIFOs) implicitly gain <varname>Requires=</varname> and - <varname>After=</varname> dependencies on all mount units - necessary to access those paths.</para> - - <para>Socket units using the <varname>BindToDevice=</varname> - setting automatically gain a <varname>BindsTo=</varname> and - <varname>After=</varname> dependency on the device unit - encapsulating the specified network interface.</para> - - <para>If <varname>DefaultDependencies=yes</varname> is set (the - default), socket units automatically gain a - <varname>Before=</varname> dependency on - <filename>sockets.target</filename>. They also gain a pair of - <varname>After=</varname> and <varname>Requires=</varname> - dependency on <filename>sysinit.target</filename>, and a pair of - <varname>Before=</varname> and <varname>Conflicts=</varname> - dependencies on <filename>shutdown.target</filename>. These - dependencies ensure that the socket unit is started before normal - services at boot, and is stopped on shutdown.</para> + <title>Implicit Dependencies</title> + + <para>The following dependencies are implicitly added:</para> + + <itemizedlist> + <listitem><para>Socket units automatically gain a <varname>Before=</varname> + dependency on the service units they activate.</para></listitem> + + <listitem><para>Socket units referring to file system paths (such as AF_UNIX + sockets or FIFOs) implicitly gain <varname>Requires=</varname> and + <varname>After=</varname> dependencies on all mount units + necessary to access those paths.</para></listitem> + + <listitem><para>Socket units using the <varname>BindToDevice=</varname> + setting automatically gain a <varname>BindsTo=</varname> and + <varname>After=</varname> dependency on the device unit + encapsulating the specified network interface.</para></listitem> + </itemizedlist> <para>Additional implicit dependencies may be added as result of execution and resource control parameters as documented in @@ -164,6 +148,29 @@ </refsect1> <refsect1> + <title>Default Dependencies</title> + + <para>The following dependencies are added unless + <varname>DefaultDependencies=no</varname> is set:</para> + + <itemizedlist> + <listitem><para>Socket units automatically gain a + <varname>Before=</varname> dependency on + <filename>sockets.target</filename>.</para></listitem> + + <listitem><para>Socket units automatically gain a pair of + <varname>After=</varname> and <varname>Requires=</varname> + dependency on <filename>sysinit.target</filename>, and a pair of + <varname>Before=</varname> and <varname>Conflicts=</varname> + dependencies on <filename>shutdown.target</filename>. These + dependencies ensure that the socket unit is started before normal + services at boot, and is stopped on shutdown. Only sockets + involved with early boot or late system shutdown should disable + <varname>DefaultDependencies=</varname> option.</para></listitem> + </itemizedlist> + </refsect1> + + <refsect1> <title>Options</title> <para>Socket files must include a [Socket] section, which carries @@ -358,7 +365,7 @@ specified network interfaces. This controls the SO_BINDTODEVICE socket option (see <citerefentry project='man-pages'><refentrytitle>socket</refentrytitle><manvolnum>7</manvolnum></citerefentry> - for details). If this option is used, an automatic dependency + for details). If this option is used, an implicit dependency from this socket unit on the network interface device unit (<citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry> is created. Note that setting this parameter might result in @@ -797,13 +804,12 @@ <varlistentry> <term><varname>Symlinks=</varname></term> - <listitem><para>Takes a list of file system paths. The - specified paths will be created as symlinks to the AF_UNIX - socket path or FIFO path of this socket unit. If this setting - is used, only one AF_UNIX socket in the file system or one - FIFO may be configured for the socket unit. Use this option to - manage one or more symlinked alias names for a socket, binding - their lifecycle together. Defaults to the empty + <listitem><para>Takes a list of file system paths. The specified paths will be created as symlinks to the + <constant>AF_UNIX</constant> socket path or FIFO path of this socket unit. If this setting is used, only one + <constant>AF_UNIX</constant> socket in the file system or one FIFO may be configured for the socket unit. Use + this option to manage one or more symlinked alias names for a socket, binding their lifecycle together. Note + that if creation of a symlink fails this is not considered fatal for the socket unit, and the socket unit may + still start. If an empty string is assigned, the list of paths is reset. Defaults to an empty list.</para></listitem> </varlistentry> |