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diff --git a/man/systemd.xml b/man/systemd.xml deleted file mode 100644 index 79d8aedbbc..0000000000 --- a/man/systemd.xml +++ /dev/null @@ -1,1157 +0,0 @@ -<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*--> -<!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" - xmlns:xi="http://www.w3.org/2001/XInclude"> - - <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 GNU/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 a system instance, systemd interprets the - configuration file <filename>system.conf</filename> and the files - in <filename>system.conf.d</filename> directories; when run as a - user instance, systemd interprets the configuration file - <filename>user.conf</filename> and the files in - <filename>user.conf.d</filename> directories. See - <citerefentry><refentrytitle>systemd-system.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>--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>--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>Enable core dumping on crash. This switch has - no effect when running as user instance. This setting may also - be enabled during boot on the kernel command line via the - <varname>systemd.dump_core=</varname> option, see - below.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>--crash-vt=</option><replaceable>VT</replaceable></term> - - <listitem><para>Switch to a specific virtual console (VT) on - crash. Takes a positive integer in the range 1–63, or a - boolean argument. If an integer is passed, selects which VT to - switch to. If <constant>yes</constant>, the VT kernel messages - are written to is selected. If <constant>no</constant>, no VT - switch is attempted. This switch has no effect when running as - user instance. This setting may also be enabled during boot, - on the kernel command line via the - <varname>systemd.crash_vt=</varname> option, see - below.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>--crash-shell</option></term> - - <listitem><para>Run a shell on crash. This switch has no - effect when running as user instance. This setting may also be - enabled during boot, on the kernel command line via the - <varname>systemd.crash_shell=</varname> option, see - below.</para></listitem> - </varlistentry> - - <varlistentry> - <term><option>--crash-reboot</option></term> - - <listitem><para>Automatically reboot the system on crash. This - switch has no effect when running as user instance. This - setting may also be enabled during boot, on the kernel command - line via the <varname>systemd.crash_reboot=</varname> option, - see below.</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>kmsg</option>, - <option>journal-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 project='man-pages'><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> - - <varlistentry> - <term><option>--machine-id=</option></term> - - <listitem><para>Override the machine-id set on the hard drive, - useful for network booting or for containers. May not be set - to all zeros.</para></listitem> - </varlistentry> - - <xi:include href="standard-options.xml" xpointer="help" /> - <xi:include href="standard-options.xml" xpointer="version" /> - </variablelist> - </refsect1> - - <refsect1> - <title>Concepts</title> - - <para>systemd provides a dependency system between various - entities called "units" of 11 different types. 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, - dynamically from system state or programmatically at runtime. - 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 start and 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>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> - - <listitem><para>Slice units may be used to group units which - manage system processes (such as service and scope units) in a - hierarchical tree for resource management purposes. See - <citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para></listitem> - - <listitem><para>Scope units are similar to service units, but - manage foreign processes instead of starting them as well. See - <citerefentry><refentrytitle>systemd.scope</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="https://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 project='man-pages'><refentrytitle>systemd-cgls</refentrytitle><manvolnum>1</manvolnum></citerefentry> - or - <citerefentry project='man-pages'><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 hostname 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 - <citerefentry><refentrytitle>systemd.generator</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</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. Full list of directories is provided in - <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. - </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. Full list of - directories is provided in - <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. - </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><constant>SIGTERM</constant></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><constant>SIGINT</constant></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>. If this signal is received more - than 7 times per 2s, an immediate reboot is triggered. - Note that pressing Ctrl-Alt-Del on the console will trigger - this signal. Hence, if a reboot is hanging, pressing - Ctrl-Alt-Del more than 7 times in 2s is a relatively safe way - to trigger an immediate reboot.</para> - - <para>systemd user managers treat this signal the same way as - <constant>SIGTERM</constant>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGWINCH</constant></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><constant>SIGPWR</constant></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><constant>SIGUSR1</constant></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><constant>SIGUSR2</constant></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>systemd-analyze dump</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGHUP</constant></term> - - <listitem><para>Reloads the complete daemon configuration. - This is mostly equivalent to <command>systemctl - daemon-reload</command>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+0</constant></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><constant>SIGRTMIN+1</constant></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><constant>SIGRTMIN+2</constant></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><constant>SIGRTMIN+3</constant></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><constant>SIGRTMIN+4</constant></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><constant>SIGRTMIN+5</constant></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><constant>SIGRTMIN+6</constant></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><constant>SIGRTMIN+13</constant></term> - - <listitem><para>Immediately halts the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+14</constant></term> - - <listitem><para>Immediately powers off the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+15</constant></term> - - <listitem><para>Immediately reboots the machine.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+16</constant></term> - - <listitem><para>Immediately reboots the machine with kexec.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+20</constant></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><constant>SIGRTMIN+21</constant></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><constant>SIGRTMIN+22</constant></term> - <term><constant>SIGRTMIN+23</constant></term> - - <listitem><para>Sets the log level to <literal>debug</literal> - (or <literal>info</literal> on - <constant>SIGRTMIN+23</constant>), as controlled via - <varname>systemd.log_level=debug</varname> (or - <varname>systemd.log_level=info</varname> on - <constant>SIGRTMIN+23</constant>) on the kernel command - line.</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+24</constant></term> - - <listitem><para>Immediately exits the manager (only available - for --user instances).</para></listitem> - </varlistentry> - - <varlistentry> - <term><constant>SIGRTMIN+26</constant></term> - <term><constant>SIGRTMIN+27</constant></term> - <term><constant>SIGRTMIN+28</constant></term> - - <listitem><para>Sets the log level to - <literal>journal-or-kmsg</literal> (or - <literal>console</literal> on - <constant>SIGRTMIN+27</constant>, <literal>kmsg</literal> on - <constant>SIGRTMIN+28</constant>), as controlled via - <varname>systemd.log_target=journal-or-kmsg</varname> (or - <varname>systemd.log_target=console</varname> on - <constant>SIGRTMIN+27</constant> or - <varname>systemd.log_target=kmsg</varname> on - <constant>SIGRTMIN+28</constant>) on the kernel command - line.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Environment</title> - - <variablelist class='environment-variables'> - <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>$SYSTEMD_SYSVRCND_PATH</varname></term> - - <listitem><para>Controls where systemd looks for SysV init - script runlevel link farms.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>$SYSTEMD_COLORS</varname></term> - - <listitem><para>The value must be a boolean. Controls whether colorized output should be - generated. This can be specified to override the decision that <command>systemd</command> - makes based on <varname>$TERM</varname> and what the console is connected to.</para> - </listitem> - </varlistentry> - - <varlistentry> - <term><varname>$LISTEN_PID</varname></term> - <term><varname>$LISTEN_FDS</varname></term> - <term><varname>$LISTEN_FDNAMES</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 class='kernel-commandline-options'> - <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 is not 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>yes</option>, the systemd manager (PID 1) dumps core - when it crashes. Otherwise, no core dump is created. Defaults - to <option>yes</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.crash_chvt=</varname></term> - - <listitem><para>Takes a positive integer, or a boolean - argument. If a positive integer (in the range 1–63) is - specified, the system manager (PID 1) will activate the specified - virtual terminal (VT) when it crashes. Defaults to - <constant>no</constant>, meaning that no such switch is - attempted. If set to <constant>yes</constant>, the VT the - kernel messages are written to is selected.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.crash_shell=</varname></term> - - <listitem><para>Takes a boolean argument. If - <option>yes</option>, the system manager (PID 1) spawns a - shell when it crashes, after a 10s delay. Otherwise, no shell - is spawned. Defaults to <option>no</option>, for security - reasons, as the shell is not protected by password - authentication.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.crash_reboot=</varname></term> - - <listitem><para>Takes a boolean argument. If - <option>yes</option>, the system manager (PID 1) will reboot - the machine automatically when it crashes, after a 10s delay. - Otherwise, the system will hang indefinitely. Defaults to - <option>no</option>, in order to avoid a reboot loop. If - combined with <varname>systemd.crash_shell=</varname>, the - system is rebooted after the shell exits.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.confirm_spawn=</varname></term> - - <listitem><para>Takes a boolean argument. If - <option>yes</option>, the system manager (PID 1) asks for - confirmation when spawning processes. Defaults to - <option>no</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.show_status=</varname></term> - - <listitem><para>Takes a boolean argument or the constant - <constant>auto</constant>. If <option>yes</option>, the - systemd manager (PID 1) shows terse service status updates on - the console during bootup. <constant>auto</constant> behaves - like <option>false</option> until a service fails or there is - a significant delay in boot. Defaults to - <option>yes</option>, unless <option>quiet</option> is passed - as kernel command line option, in which case it defaults to - <constant>auto</constant>.</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 default environment - variables to add to forked child processes. May be used more - than once to set multiple variables.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>systemd.machine_id=</varname></term> - - <listitem><para>Takes a 32 character hex value to be - used for setting the machine-id. Intended mostly for - network booting where the same machine-id is desired - for every boot.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>quiet</varname></term> - - <listitem><para>Turn 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. Passing this option hence turns off the - usual output from both the system manager and the kernel. - </para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>debug</varname></term> - - <listitem><para>Turn on debugging output. This is equivalent - to <varname>systemd.log_level=debug</varname>. Note that this - option is also read by the kernel itself and enables kernel - debug output. Passing this option hence turns on the debug - output from both the system manager and the - kernel.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>emergency</varname></term> - <term><varname>rd.emergency</varname></term> - <term><varname>-b</varname></term> - - <listitem><para>Boot into emergency mode. This is equivalent - to <varname>systemd.unit=emergency.target</varname> or - <varname>rd.systemd.unit=emergency.target</varname>, respectively, and - provided for compatibility reasons and to be easier to type.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>rescue</varname></term> - <term><varname>rd.rescue</varname></term> - <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> or - <varname>rd.systemd.unit=rescue.target</varname>, respectively, 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 project='man-pages'><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry> - and - <citerefentry project='man-pages'><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 - <constant>AF_UNIX</constant> 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/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 - <constant>AF_UNIX</constant> 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> - The <ulink url="http://www.freedesktop.org/wiki/Software/systemd/">systemd Homepage</ulink>, - <citerefentry><refentrytitle>systemd-system.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry project='man-pages'><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 project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |