diff options
| author | Anthony G. Basile <blueness@gentoo.org> | 2012-11-15 10:33:16 -0500 |
|---|---|---|
| committer | Anthony G. Basile <blueness@gentoo.org> | 2012-11-15 10:33:16 -0500 |
| commit | 7d4a62f8c1404ed426500b97af03d4ef8d034a71 (patch) | |
| tree | 2436cd4f0460a3a3d589875d4ffba55556f3c582 /man/systemd.xml | |
| parent | 2944f347d087ff24ec808e4b70fe104a772a97a0 (diff) | |
Isolation of udev code from remaining systemd
This commit is a first attempt to isolate the udev code from the
remaining code base. It intentionally does not modify any files
but purely delete files which, on a first examination, appear to
not be needed. This is a sweeping commit which may easily have
missed needed code. Files can be retrieved by doing a checkout
from the previous commit:
git checkout 2944f347d0 -- <filename>
Diffstat (limited to 'man/systemd.xml')
| -rw-r--r-- | man/systemd.xml | 1272 |
1 files changed, 0 insertions, 1272 deletions
diff --git a/man/systemd.xml b/man/systemd.xml deleted file mode 100644 index 7b3d265b8d..0000000000 --- a/man/systemd.xml +++ /dev/null @@ -1,1272 +0,0 @@ -<?xml version='1.0'?> <!--*-nxml-*--> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" - "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<!-- - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - 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 - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="systemd"> - - <refentryinfo> - <title>systemd</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>systemd</refentrytitle> - <manvolnum>1</manvolnum> - </refmeta> - - <refnamediv> - <refname>systemd</refname> - <refname>init</refname> - <refpurpose>systemd system and service manager</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <cmdsynopsis> - <command>systemd <arg choice="opt" rep="repeat">OPTIONS</arg></command> - </cmdsynopsis> - <cmdsynopsis> - <command>init <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command> - </cmdsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para>systemd is a system and service manager for - Linux operating systems. When run as first process on - boot (as PID 1), it acts as init system that brings - up and maintains userspace services.</para> - - <para>For compatibility with SysV, if systemd is called - as <command>init</command> and a PID that is not - 1, it will execute <command>telinit</command> and pass - all command line arguments unmodified. That means - <command>init</command> and <command>telinit</command> - are mostly equivalent when invoked from normal login sessions. See - <citerefentry><refentrytitle>telinit</refentrytitle><manvolnum>8</manvolnum></citerefentry> - for more information.</para> - - <para>When run as system instance, systemd interprets - the configuration file - <filename>system.conf</filename>, otherwise - <filename>user.conf</filename>. See - <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> - for more information.</para> - </refsect1> - - <refsect1> - <title>Options</title> - - <para>The following options are understood:</para> - - <variablelist> - <varlistentry> - <term><option>-h</option></term> - <term><option>--help</option></term> - - <listitem><para>Prints a short help - text and exits.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--version</option></term> - - <listitem><para>Prints a systemd version - identifier and exits.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--test</option></term> - - <listitem><para>Determine startup - sequence, dump it and exit. This is an - option useful for debugging - only.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--dump-configuration-items</option></term> - - <listitem><para>Dump understood unit - configuration items. This outputs a - terse but complete list of - configuration items understood in unit - definition files.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--introspect=</option></term> - - <listitem><para>Extract D-Bus - interface introspection data. This is - mostly useful at install time - to generate data suitable for the - D-Bus interfaces - repository. Optionally the interface - name for the introspection data may be - specified. If omitted, the - introspection data for all interfaces - is dumped.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--unit=</option></term> - - <listitem><para>Set default unit to - activate on startup. If not specified - defaults to - <filename>default.target</filename>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--system</option></term> - <term><option>--user</option></term> - - <listitem><para>For <option>--system</option>, - tell systemd to run a - system instance, even if the process ID is - not 1, i.e. systemd is not run as init process. - <option>--user</option> does the opposite, - running a user instance even if the process - ID is 1. - Normally it should not be necessary to - pass these options, as systemd - automatically detects the mode it is - started in. These options are hence of - little use except for debugging. Note - that it is not supported booting and - maintaining a full system with systemd - running in <option>--system</option> - mode, but PID not 1. In practice, - passing <option>--system</option> explicitly is - only useful in conjunction with - <option>--test</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--dump-core</option></term> - - <listitem><para>Dump core on - crash. This switch has no effect when - run as user - instance.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--crash-shell</option></term> - - <listitem><para>Run shell on - crash. This switch has no effect when - run as user - instance.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--confirm-spawn</option></term> - - <listitem><para>Ask for confirmation - when spawning processes. This switch - has no effect when run as user - instance.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--show-status=</option></term> - - <listitem><para>Show terse service - status information while booting. This - switch has no effect when run as user - instance. Takes a boolean argument - which may be omitted which is - interpreted as - <option>true</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--log-target=</option></term> - - <listitem><para>Set log - target. Argument must be one of - <option>console</option>, - <option>journal</option>, - <option>syslog</option>, - <option>kmsg</option>, - <option>journal-or-kmsg</option>, - <option>syslog-or-kmsg</option>, - <option>null</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--log-level=</option></term> - - <listitem><para>Set log level. As - argument this accepts a numerical log - level or the well-known <citerefentry><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry> - symbolic names (lowercase): - <option>emerg</option>, - <option>alert</option>, - <option>crit</option>, - <option>err</option>, - <option>warning</option>, - <option>notice</option>, - <option>info</option>, - <option>debug</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--log-color=</option></term> - - <listitem><para>Highlight important - log messages. Argument is a boolean - value. If the argument is omitted it - defaults to - <option>true</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--log-location=</option></term> - - <listitem><para>Include code location - in log messages. This is mostly - relevant for debugging - purposes. Argument is a boolean - value. If the argument is omitted - it defaults to - <option>true</option>.</para></listitem> - </varlistentry> - <varlistentry> - <term><option>--default-standard-output=</option></term> - <term><option>--default-standard-error=</option></term> - - <listitem><para>Sets the default - output or error output for all - services and sockets, respectively. That is, controls - the default for - <option>StandardOutput=</option> - and <option>StandardError=</option> - (see - <citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> - for details). Takes one of - <option>inherit</option>, - <option>null</option>, - <option>tty</option>, - <option>journal</option>, - <option>journal+console</option>, - <option>syslog</option>, - <option>syslog+console</option>, - <option>kmsg</option>, - <option>kmsg+console</option>. If the - argument is omitted - <option>--default-standard-output=</option> - defaults to <option>journal</option> - and - <option>--default-standard-error=</option> - to - <option>inherit</option>.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Concepts</title> - - <para>systemd provides a dependency system between - various entities called "units". Units encapsulate - various objects that are relevant for system boot-up - and maintenance. The majority of units are configured - in unit configuration files, whose syntax and basic - set of options is described in - <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - however some are created automatically from other - configuration or dynamically from system state. Units - may be 'active' (meaning started, bound, plugged in, - ... depending on the unit type, see below), or - 'inactive' (meaning stopped, unbound, unplugged, ...), - as well as in the process of being activated or - deactivated, i.e. between the two states (these states - are called 'activating', 'deactivating'). A special - 'failed' state is available as well which is very - similar to 'inactive' and is entered when the service - failed in some way (process returned error code on - exit, or crashed, or an operation timed out). If this - state is entered the cause will be logged, for later - reference. Note that the various unit types may have a - number of additional substates, which are mapped to - the five generalized unit states described - here.</para> - - <para>The following unit types are available:</para> - - <orderedlist> - <listitem><para>Service units, which control - daemons and the processes they consist of. For - details see - <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Socket units, which - encapsulate local IPC or network sockets in - the system, useful for socket-based - activation. For details about socket units see - <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - for details on socket-based activation and - other forms of activation, see - <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Target units are useful to - group units, or provide well-known - synchronization points during boot-up, see - <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Device units expose kernel - devices in systemd and may be used to - implement device-based activation. For details - see - <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Mount units control mount - points in the file system, for details see - <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Automount units provide - automount capabilities, for on-demand mounting - of file systems as well as parallelized - boot-up. See - <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Snapshot units can be used to - temporarily save the state of the set of - systemd units, which later may be restored by - activating the saved snapshot unit. For more - information see - <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Timer units are useful for - triggering activation of other units based on - timers. You may find details in - <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Swap units are very similar to - mount units and encapsulate memory swap - partitions or files of the operating - system. They are described in <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Path units may be used - to activate other services when file system - objects change or are modified. See - <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - </orderedlist> - - <para>Units are named as their configuration - files. Some units have special semantics. A detailed - list is available in - <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> - - <para>systemd knows various kinds of dependencies, - including positive and negative requirement - dependencies (i.e. <varname>Requires=</varname> and - <varname>Conflicts=</varname>) as well as ordering - dependencies (<varname>After=</varname> and - <varname>Before=</varname>). NB: ordering and - requirement dependencies are orthogonal. If only a - requirement dependency exists between two units - (e.g. <filename>foo.service</filename> requires - <filename>bar.service</filename>), but no ordering - dependency (e.g. <filename>foo.service</filename> - after <filename>bar.service</filename>) and both are - requested to start, they will be started in - parallel. It is a common pattern that both requirement - and ordering dependencies are placed between two - units. Also note that the majority of dependencies are - implicitly created and maintained by systemd. In most - cases it should be unnecessary to declare additional - dependencies manually, however it is possible to do - this.</para> - - <para>Application programs and units (via - dependencies) may request state changes of units. In - systemd, these requests are encapsulated as 'jobs' and - maintained in a job queue. Jobs may succeed or can - fail, their execution is ordered based on the ordering - dependencies of the units they have been scheduled - for.</para> - - <para>On boot systemd activates the target unit - <filename>default.target</filename> whose job is to - activate on-boot services and other on-boot units by - pulling them in via dependencies. Usually the unit - name is just an alias (symlink) for either - <filename>graphical.target</filename> (for - fully-featured boots into the UI) or - <filename>multi-user.target</filename> (for limited - console-only boots for use in embedded or server - environments, or similar; a subset of - graphical.target). However it is at the discretion of - the administrator to configure it as an alias to any - other target unit. See - <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> - for details about these target units.</para> - - <para>Processes systemd spawns are placed in - individual Linux control groups named after the unit - which they belong to in the private systemd - hierarchy. (see <ulink - url="http://www.kernel.org/doc/Documentation/cgroups/cgroups.txt">cgroups.txt</ulink> - for more information about control groups, or short - "cgroups"). systemd uses this to effectively keep - track of processes. Control group information is - maintained in the kernel, and is accessible via the - file system hierarchy (beneath - <filename>/sys/fs/cgroup/systemd/</filename>), or in tools - such as - <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry> - (<command>ps xawf -eo pid,user,cgroup,args</command> - is particularly useful to list all processes and the - systemd units they belong to.).</para> - - <para>systemd is compatible with the SysV init system - to a large degree: SysV init scripts are supported and - simply read as an alternative (though limited) - configuration file format. The SysV - <filename>/dev/initctl</filename> interface is - provided, and compatibility implementations of the - various SysV client tools are available. In addition to - that, various established Unix functionality such as - <filename>/etc/fstab</filename> or the - <filename>utmp</filename> database are - supported.</para> - - <para>systemd has a minimal transaction system: if a - unit is requested to start up or shut down it will add - it and all its dependencies to a temporary - transaction. Then, it will verify if the transaction - is consistent (i.e. whether the ordering of all units - is cycle-free). If it is not, systemd will try to fix - it up, and removes non-essential jobs from the - transaction that might remove the loop. Also, systemd - tries to suppress non-essential jobs in the - transaction that would stop a running service. Finally - it is checked whether the jobs of the transaction - contradict jobs that have already been queued, and - optionally the transaction is aborted then. If all - worked out and the transaction is consistent and - minimized in its impact it is merged with all already - outstanding jobs and added to the run - queue. Effectively this means that before executing a - requested operation, systemd will verify that it makes - sense, fixing it if possible, and only failing if it - really cannot work.</para> - - <para>Systemd contains native implementations of - various tasks that need to be executed as part of the - boot process. For example, it sets the host name or - configures the loopback network device. It also sets - up and mounts various API file systems, such as - <filename>/sys</filename> or - <filename>/proc</filename>.</para> - - <para>For more information about the concepts and - ideas behind systemd please refer to the <ulink - url="http://0pointer.de/blog/projects/systemd.html">Original - Design Document</ulink>.</para> - - <para>Note that some but not all interfaces provided - by systemd are covered by the <ulink - url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface - Stability Promise</ulink>.</para> - - <para>Units may be generated dynamically at boot and - system manager reload time, for example based on other - configuration files or parameters passed on the kernel - command line. For details see the <ulink - url="http://www.freedesktop.org/wiki/Software/systemd/Generators">Generators - Specification</ulink>.</para> - - <para>Systems which invoke systemd in a container - or initrd environment should implement the - <ulink - url="http://www.freedesktop.org/wiki/Software/systemd/ContainerInterface">Container - Interface</ulink> or <ulink - url="http://www.freedesktop.org/wiki/Software/systemd/InitrdInterface">initrd - Interface</ulink> specifications, respectively.</para> - </refsect1> - - <refsect1> - <title>Directories</title> - - <variablelist> - <varlistentry> - <term>System unit directories</term> - - <listitem><para>The systemd system - manager reads unit configuration from - various directories. Packages that - want to install unit files shall place - them in the directory returned by - <command>pkg-config systemd - --variable=systemdsystemunitdir</command>. Other - directories checked are - <filename>/usr/local/lib/systemd/system</filename> - and - <filename>/usr/lib/systemd/system</filename>. User - configuration always takes - precedence. <command>pkg-config - systemd - --variable=systemdsystemconfdir</command> - returns the path of the system - configuration directory. Packages - should alter the content of these - directories only with the - <command>enable</command> and - <command>disable</command> commands of - the - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> - tool.</para></listitem> - </varlistentry> - </variablelist> - - <variablelist> - <varlistentry> - <term>User unit directories</term> - - <listitem><para>Similar rules apply - for the user unit - directories. However, here the <ulink - url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG - Base Directory specification</ulink> - is followed to find - units. Applications should place their - unit files in the directory returned - by <command>pkg-config systemd - --variable=systemduserunitdir</command>. Global - configuration is done in the directory - reported by <command>pkg-config - systemd - --variable=systemduserconfdir</command>. The - <command>enable</command> and - <command>disable</command> commands of - the - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> - tool can handle both global (i.e. for - all users) and private (for one user) - enabling/disabling of - units.</para></listitem> - </varlistentry> - </variablelist> - - <variablelist> - <varlistentry> - <term>SysV init scripts directory</term> - - <listitem><para>The location of the - SysV init script directory varies - between distributions. If systemd - cannot find a native unit file for a - requested service, it will look for a - SysV init script of the same name - (with the - <filename>.service</filename> suffix - removed).</para></listitem> - </varlistentry> - </variablelist> - - <variablelist> - <varlistentry> - <term>SysV runlevel link farm directory</term> - - <listitem><para>The location of the - SysV runlevel link farm directory - varies between distributions. systemd - will take the link farm into account - when figuring out whether a service - shall be enabled. Note that a service - unit with a native unit configuration - file cannot be started by activating it - in the SysV runlevel link - farm.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Signals</title> - - <variablelist> - <varlistentry> - <term>SIGTERM</term> - - <listitem><para>Upon receiving this - signal the systemd system manager - serializes its state, reexecutes - itself and deserializes the saved - state again. This is mostly equivalent - to <command>systemctl - daemon-reexec</command>.</para> - - <para>systemd user managers will - start the - <filename>exit.target</filename> unit - when this signal is received. This is - mostly equivalent to - <command>systemctl --user start - exit.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGINT</term> - - <listitem><para>Upon receiving this - signal the systemd system manager will - start the - <filename>ctrl-alt-del.target</filename> unit. This - is mostly equivalent to - <command>systemctl start - ctl-alt-del.target</command>.</para> - - <para>systemd user managers - treat this signal the same way as - SIGTERM.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGWINCH</term> - - <listitem><para>When this signal is - received the systemd system manager - will start the - <filename>kbrequest.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - kbrequest.target</command>.</para> - - <para>This signal is ignored by - systemd user - managers.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGPWR</term> - - <listitem><para>When this signal is - received the systemd manager - will start the - <filename>sigpwr.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - sigpwr.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGUSR1</term> - - <listitem><para>When this signal is - received the systemd manager will try - to reconnect to the D-Bus - bus.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGUSR2</term> - - <listitem><para>When this signal is - received the systemd manager will log - its complete state in human readable - form. The data logged is the same as - printed by <command>systemctl - dump</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGHUP</term> - - <listitem><para>Reloads the complete - daemon configuration. This is mostly - equivalent to <command>systemctl - daemon-reload</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+0</term> - - <listitem><para>Enters default mode, starts the - <filename>default.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - default.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+1</term> - - <listitem><para>Enters rescue mode, - starts the - <filename>rescue.target</filename> - unit. This is mostly equivalent to - <command>systemctl isolate - rescue.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+2</term> - - <listitem><para>Enters emergency mode, - starts the - <filename>emergency.service</filename> - unit. This is mostly equivalent to - <command>systemctl isolate - emergency.service</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+3</term> - - <listitem><para>Halts the machine, - starts the - <filename>halt.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - halt.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+4</term> - - <listitem><para>Powers off the machine, - starts the - <filename>poweroff.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - poweroff.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+5</term> - - <listitem><para>Reboots the machine, - starts the - <filename>reboot.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - reboot.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+6</term> - - <listitem><para>Reboots the machine via kexec, - starts the - <filename>kexec.target</filename> - unit. This is mostly equivalent to - <command>systemctl start - kexec.target</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+13</term> - - <listitem><para>Immediately halts the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+14</term> - - <listitem><para>Immediately powers off the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+15</term> - - <listitem><para>Immediately reboots the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+16</term> - - <listitem><para>Immediately reboots the machine with kexec.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+20</term> - - <listitem><para>Enables display of - status messages on the console, as - controlled via - <varname>systemd.show_status=1</varname> - on the kernel command - line.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+21</term> - - <listitem><para>Disables display of - status messages on the console, as - controlled via - <varname>systemd.show_status=0</varname> - on the kernel command - line.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+22</term> - <term>SIGRTMIN+23</term> - - <listitem><para>Sets the log level to - <literal>debug</literal> - (or <literal>info</literal> on - <literal>SIGRTMIN+23</literal>), as - controlled via - <varname>systemd.log_level=debug</varname> - (or <varname>systemd.log_level=info</varname> - on <literal>SIGRTMIN+23</literal>) on - the kernel command - line.</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+24</term> - - <listitem><para>Immediately exits the - manager (only available for --user - instances).</para></listitem> - </varlistentry> - - <varlistentry> - <term>SIGRTMIN+26</term> - <term>SIGRTMIN+27</term> - <term>SIGRTMIN+28</term> - <term>SIGRTMIN+29</term> - - <listitem><para>Sets the log level to - <literal>journal-or-kmsg</literal> - (or <literal>console</literal> on - <literal>SIGRTMIN+27</literal>, - <literal>kmsg</literal> on - <literal>SIGRTMIN+28</literal>, - or <literal>syslog-or-kmsg</literal> - on <literal>SIGRTMIN+29</literal>), as - controlled via - <varname>systemd.log_target=journal-or-kmsg</varname> - (or <varname>systemd.log_target=console</varname> - on <literal>SIGRTMIN+27</literal>, - <varname>systemd.log_target=kmsg</varname> - on <literal>SIGRTMIN+28</literal>, - or - <varname>systemd.log_target=syslog-or-kmsg</varname> - on <literal>SIGRTMIN+29</literal>) on - the kernel command - line.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Environment</title> - - <variablelist> - <varlistentry> - <term><varname>$SYSTEMD_LOG_LEVEL</varname></term> - <listitem><para>systemd reads the - log level from this environment - variable. This can be overridden with - <option>--log-level=</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_LOG_TARGET</varname></term> - <listitem><para>systemd reads the - log target from this environment - variable. This can be overridden with - <option>--log-target=</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_LOG_COLOR</varname></term> - <listitem><para>Controls whether - systemd highlights important log - messages. This can be overridden with - <option>--log-color=</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_LOG_LOCATION</varname></term> - <listitem><para>Controls whether - systemd prints the code location along - with log messages. This can be - overridden with - <option>--log-location=</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$XDG_CONFIG_HOME</varname></term> - <term><varname>$XDG_CONFIG_DIRS</varname></term> - <term><varname>$XDG_DATA_HOME</varname></term> - <term><varname>$XDG_DATA_DIRS</varname></term> - - <listitem><para>The systemd user - manager uses these variables in - accordance to the <ulink - url="http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html">XDG - Base Directory specification</ulink> - to find its configuration.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_UNIT_PATH</varname></term> - - <listitem><para>Controls where systemd - looks for unit - files.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_SYSVINIT_PATH</varname></term> - - <listitem><para>Controls where systemd - looks for SysV init scripts.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_SYSVRCND_PATH</varname></term> - - <listitem><para>Controls where systemd - looks for SysV init script runlevel link - farms.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$LISTEN_PID</varname></term> - <term><varname>$LISTEN_FDS</varname></term> - - <listitem><para>Set by systemd for - supervised processes during - socket-based activation. See - <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry> - for more information. - </para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$NOTIFY_SOCKET</varname></term> - - <listitem><para>Set by systemd for - supervised processes for status and - start-up completion notification. See - <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry> - for more information. - </para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Kernel Command Line</title> - - <para>When run as system instance systemd parses a - number of kernel command line - arguments<footnote><para>If run inside a Linux - container these arguments may be passed as command - line arguments to systemd itself, next to any of the - command line options listed in the Options section - above. If run outside of Linux containers, these - arguments are parsed from - <filename>/proc/cmdline</filename> - instead.</para></footnote>:</para> - - <variablelist> - <varlistentry> - <term><varname>systemd.unit=</varname></term> - <term><varname>rd.systemd.unit=</varname></term> - - <listitem><para>Overrides the unit to - activate on boot. Defaults to - <filename>default.target</filename>. This - may be used to temporarily boot into a - different boot unit, for example - <filename>rescue.target</filename> or - <filename>emergency.service</filename>. See - <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry> - for details about these units. The - option prefixed with - <literal>rd.</literal> is honored - only in the initial RAM disk (initrd), - while the one that isn't prefixed only - in the main system.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.dump_core=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - systemd dumps core when it - crashes. Otherwise no core dump is - created. Defaults to - <option>true</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.crash_shell=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - systemd spawns a shell when it - crashes. Otherwise no shell is - spawned. Defaults to - <option>false</option>, for security - reasons, as the shell is not protected - by any password - authentication.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.crash_chvt=</varname></term> - - <listitem><para>Takes an integer - argument. If positive systemd - activates the specified virtual - terminal when it crashes. Defaults to - <literal>-1</literal>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.confirm_spawn=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - asks for confirmation when spawning - processes. Defaults to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.show_status=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - shows terse service status updates on - the console during bootup. Defaults to - <option>true</option>, unless - <option>quiet</option> is passed as - kernel command line option in which - case it defaults to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.log_target=</varname></term> - <term><varname>systemd.log_level=</varname></term> - <term><varname>systemd.log_color=</varname></term> - <term><varname>systemd.log_location=</varname></term> - - <listitem><para>Controls log output, - with the same effect as the - <varname>$SYSTEMD_LOG_TARGET</varname>, <varname>$SYSTEMD_LOG_LEVEL</varname>, <varname>$SYSTEMD_LOG_COLOR</varname>, <varname>$SYSTEMD_LOG_LOCATION</varname> - environment variables described above.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.default_standard_output=</varname></term> - <term><varname>systemd.default_standard_error=</varname></term> - <listitem><para>Controls default - standard output and error output for - services, with the same effect as the - <option>--default-standard-output=</option> - and <option>--default-standard-error=</option> - command line arguments described - above, respectively.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.setenv=</varname></term> - - <listitem><para>Takes a string - argument in the form - VARIABLE=VALUE. May be used to set - environment variables for the init - process and all its children at boot - time. May be used more than once to - set multiple variables. If the equal - sign and variable are missing it unsets - an environment variable which might be - passed in from the initial ram - disk.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>quiet</varname></term> - - <listitem><para>If passed turns off - status output at boot, much like - <varname>systemd.show_status=false</varname> - would. Note that this option is also - read by the kernel itself and disables - kernel log output to the - kernel. Passing this option hence - turns off the usual output from both - the system manager and the - kernel.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>emergency</varname></term> - - <listitem><para>Boot into emergency - mode. This is equivalent to - <varname>systemd.unit=emergency.target</varname> - and provided for compatibility - reasons and to be easier to type.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>single</varname></term> - <term><varname>s</varname></term> - <term><varname>S</varname></term> - <term><varname>1</varname></term> - - <listitem><para>Boot into rescue - mode. This is equivalent to - <varname>systemd.unit=rescue.target</varname> - and provided for compatibility reasons - and to be easier to - type.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>2</varname></term> - <term><varname>3</varname></term> - <term><varname>4</varname></term> - <term><varname>5</varname></term> - - <listitem><para>Boot into the - specified legacy SysV runlevel. These - are equivalent to - <varname>systemd.unit=runlevel2.target</varname>, - <varname>systemd.unit=runlevel3.target</varname>, - <varname>systemd.unit=runlevel4.target</varname>, - and <varname>systemd.unit=runlevel5.target</varname>, respectively, - and provided for compatibility reasons - and to be easier to - type.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>locale.LANG=</varname></term> - <term><varname>locale.LANGUAGE=</varname></term> - <term><varname>locale.LC_CTYPE=</varname></term> - <term><varname>locale.LC_NUMERIC=</varname></term> - <term><varname>locale.LC_TIME=</varname></term> - <term><varname>locale.LC_COLLATE=</varname></term> - <term><varname>locale.LC_MONETARY=</varname></term> - <term><varname>locale.LC_MESSAGES=</varname></term> - <term><varname>locale.LC_PAPER=</varname></term> - <term><varname>locale.LC_NAME=</varname></term> - <term><varname>locale.LC_ADDRESS=</varname></term> - <term><varname>locale.LC_TELEPHONE=</varname></term> - <term><varname>locale.LC_MEASUREMENT=</varname></term> - <term><varname>locale.LC_IDENTIFICATION=</varname></term> - - <listitem><para>Set the system locale - to use. This overrides the settings in - <filename>/etc/locale.conf</filename>. For - more information see - <citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> - and - <citerefentry><refentrytitle>locale</refentrytitle><manvolnum>7</manvolnum></citerefentry>. - </para></listitem> - </varlistentry> - </variablelist> - - <para>For other kernel command line parameters - understood by components of the core OS, please refer - to - <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> - </refsect1> - - <refsect1> - <title>Sockets and FIFOs</title> - - <variablelist> - <varlistentry> - <term><filename>/run/systemd/notify</filename></term> - - <listitem><para>Daemon status - notification socket. This is an - AF_UNIX datagram socket and is used to - implement the daemon notification - logic as implemented by - <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem> - - </varlistentry> - - <varlistentry> - <term><filename>/run/systemd/shutdownd</filename></term> - - <listitem><para>Used internally by the - <citerefentry><refentrytitle>shutdown</refentrytitle><manvolnum>8</manvolnum></citerefentry> - tool to implement delayed - shutdowns. This is an AF_UNIX datagram - socket.</para></listitem> - </varlistentry> - - <varlistentry> - <term><filename>/run/systemd/private</filename></term> - - <listitem><para>Used internally as - communication channel between - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> - and the systemd process. This is an - AF_UNIX stream socket. This interface - is private to systemd and should not - be used in external - projects.</para></listitem> - </varlistentry> - - <varlistentry> - <term><filename>/dev/initctl</filename></term> - - <listitem><para>Limited compatibility - support for the SysV client interface, - as implemented by the - <filename>systemd-initctl.service</filename> - unit. This is a named pipe in the file - system. This interface is obsolete and - should not be used in new - applications.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <citerefentry><refentrytitle>systemd.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd-notify</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>daemon</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>sd-daemon</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |