along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
-<refentry id="systemd">
+<refentry id="systemd"
+ xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd</title>
<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
+ <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>
<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>
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
+ activate on startup. If not specified,
defaults to
<filename>default.target</filename>.</para></listitem>
</varlistentry>
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>
<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>
+ 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>,
<listitem><para>Highlight important
log messages. Argument is a boolean
- value. If the argument is omitted it
+ value. If the argument is omitted, it
defaults to
<option>true</option>.</para></listitem>
</varlistentry>
to
<option>inherit</option>.</para></listitem>
</varlistentry>
+
+ <xi:include href="standard-options.xml" xpointer="help" />
+ <xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</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
+ various entities called "units" of 12 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 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
+ 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
<para>The following unit types are available:</para>
<orderedlist>
- <listitem><para>Service units, which control
+ <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>
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
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
+ cases, it should be unnecessary to declare additional
dependencies manually, however it is possible to do
this.</para>
<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
+ 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>
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>
+ 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
file system hierarchy (beneath
<filename>/sys/fs/cgroup/systemd/</filename>), or in tools
such as
- <citerefentry><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ <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 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
+ 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
+ ideas behind systemd
, please refer to the <ulink
url="http://0pointer.de/blog/projects/systemd.html">Original
Design Document</ulink>.</para>
<refsect1>
<title>Directories</title>
- <variablelist class='unit-directives'>
+ <variablelist>
<varlistentry>
<term>System unit directories</term>
<variablelist>
<varlistentry>
- <term>SIGTERM</term>
+ <term><constant>SIGTERM</constant></term>
<listitem><para>Upon receiving this
signal the systemd system manager
</varlistentry>
<varlistentry>
- <term>SIGINT</term>
+ <term><constant>SIGINT</constant></term>
<listitem><para>Upon receiving this
signal the systemd system manager will
<para>systemd user managers
treat this signal the same way as
- SIGTERM.</para></listitem>
+ <constant>SIGTERM</constant>.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGWINCH</term>
+ <term><constant>SIGWINCH</constant></term>
<listitem><para>When this signal is
received the systemd system manager
</varlistentry>
<varlistentry>
- <term>SIGPWR</term>
+ <term><constant>SIGPWR</constant></term>
<listitem><para>When this signal is
received the systemd manager
</varlistentry>
<varlistentry>
- <term>SIGUSR1</term>
+ <term><constant>SIGUSR1</constant></term>
<listitem><para>When this signal is
received the systemd manager will try
</varlistentry>
<varlistentry>
- <term>SIGUSR2</term>
+ <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>systemctl
+ printed by <command>systemd-analyze
dump</command>.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGHUP</term>
+ <term><constant>SIGHUP</constant></term>
<listitem><para>Reloads the complete
daemon configuration. This is mostly
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+0</term>
+ <term><constant>SIGRTMIN+0</constant></term>
<listitem><para>Enters default mode, starts the
<filename>default.target</filename>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+1</term>
+ <term><constant>SIGRTMIN+1</constant></term>
<listitem><para>Enters rescue mode,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+2</term>
+ <term><constant>SIGRTMIN+2</constant></term>
<listitem><para>Enters emergency mode,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+3</term>
+ <term><constant>SIGRTMIN+3</constant></term>
<listitem><para>Halts the machine,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+4</term>
+ <term><constant>SIGRTMIN+4</constant></term>
<listitem><para>Powers off the machine,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+5</term>
+ <term><constant>SIGRTMIN+5</constant></term>
<listitem><para>Reboots the machine,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+6</term>
+ <term><constant>SIGRTMIN+6</constant></term>
<listitem><para>Reboots the machine via kexec,
starts the
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+13</term>
+ <term><constant>SIGRTMIN+13</constant></term>
<listitem><para>Immediately halts the machine.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+14</term>
+ <term><constant>SIGRTMIN+14</constant></term>
<listitem><para>Immediately powers off the machine.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+15</term>
+ <term><constant>SIGRTMIN+15</constant></term>
<listitem><para>Immediately reboots the machine.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+16</term>
+ <term><constant>SIGRTMIN+16</constant></term>
<listitem><para>Immediately reboots the machine with kexec.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+20</term>
+ <term><constant>SIGRTMIN+20</constant></term>
<listitem><para>Enables display of
status messages on the console, as
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+21</term>
+ <term><constant>SIGRTMIN+21</constant></term>
<listitem><para>Disables display of
status messages on the console, as
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+22</term>
- <term>SIGRTMIN+23</term>
+ <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
- <literal>SIGRTMIN+23</literal>), as
+ <constant>SIGRTMIN+23</constant>), as
controlled via
<varname>systemd.log_level=debug</varname>
(or <varname>systemd.log_level=info</varname>
- on <literal>SIGRTMIN+23</literal>) on
+ on <constant>SIGRTMIN+23</constant>) on
the kernel command
line.</para></listitem>
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+24</term>
+ <term><constant>SIGRTMIN+24</constant></term>
<listitem><para>Immediately exits the
manager (only available for --user
</varlistentry>
<varlistentry>
- <term>SIGRTMIN+26</term>
- <term>SIGRTMIN+27</term>
- <term>SIGRTMIN+28</term>
- <term>SIGRTMIN+29</term>
+ <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
- <literal>SIGRTMIN+27</literal>,
+ <literal>journal-or-kmsg</literal> (or
+ <literal>console</literal> on
+ <constant>SIGRTMIN+27</constant>,
<literal>kmsg</literal> on
- <literal>SIGRTMIN+28</literal>,
- or <literal>syslog-or-kmsg</literal>
- on <literal>SIGRTMIN+29</literal>), as
+ <constant>SIGRTMIN+28</constant>), as
controlled via
<varname>systemd.log_target=journal-or-kmsg</varname>
- (or <varname>systemd.log_target=console</varname>
- on <literal>SIGRTMIN+27</literal>,
+ (or
+ <varname>systemd.log_target=console</varname>
+ on <constant>SIGRTMIN+27</constant> or
<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
+ on <constant>SIGRTMIN+28</constant>)
+ on the kernel command
line.</para></listitem>
</varlistentry>
</variablelist>
option prefixed with
<literal>rd.</literal> is honored
only in the initial RAM disk (initrd),
- while the one that isn't prefixed only
+ while the one that is not prefixed only
in the main system.</para></listitem>
</varlistentry>
<term><varname>systemd.dump_core=</varname></term>
<listitem><para>Takes a boolean
- argument. If <option>true</option>
+ argument. If <option>true</option>,
systemd dumps core when it
- crashes. Otherwise no core dump is
+ crashes. Otherwise, no core dump is
created. Defaults to
<option>true</option>.</para></listitem>
</varlistentry>
<term><varname>systemd.crash_shell=</varname></term>
<listitem><para>Takes a boolean
- argument. If <option>true</option>
+ argument. If <option>true</option>,
systemd spawns a shell when it
- crashes. Otherwise no shell is
+ crashes. Otherwise, no shell is
spawned. Defaults to
<option>false</option>, for security
reasons, as the shell is not protected
argument. If positive systemd
activates the specified virtual
terminal when it crashes. Defaults to
- <literal>-1</literal>.</para></listitem>
+ <constant>-1</constant>.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>systemd.confirm_spawn=</varname></term>
<listitem><para>Takes a boolean
- argument. If <option>true</option>
+ argument. If <option>true</option>,
asks for confirmation when spawning
processes. Defaults to
<option>false</option>.</para></listitem>
<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
+ argument or the constant
+ <constant>auto</constant>. If
+ <option>true</option>, 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>true</option>, unless
<option>quiet</option> is passed as
kernel command line option in which
case it defaults to
- <option>false</option>.</para></listitem>
+ <constant>auto</constant>.</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>
+ 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>quiet</varname></term>
- <listitem><para>If passed turns off
+ <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 to the
- kernel. Passing this option hence
- turns off the usual output from both
- the system manager and the
+ 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>-b</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>
+ and provided for compatibility reasons
+ and to be easier to
+ type.</para></listitem>
</varlistentry>
<varlistentry>
+ <term><varname>rescue</varname></term>
<term><varname>single</varname></term>
<term><varname>s</varname></term>
<term><varname>S</varname></term>
<listitem><para>Daemon status
notification socket. This is an
- AF_UNIX datagram socket and is used to
+ <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>
<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
+ shutdowns. This is an <constant>AF_UNIX</constant> datagram
socket.</para></listitem>
</varlistentry>
communication channel between
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
and the systemd process. This is an
- AF_UNIX stream socket. This interface
+ <constant>AF_UNIX</constant> stream socket. This interface
is private to systemd and should not
be used in external
projects.</para></listitem>
<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><refentrytitle>locale.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</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 project='die-net'><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>,
+ <citerefentry project='man-pages'><refentrytitle>bootup</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
</para>
</refsect1>
~ianmdlvl / elogind.git / blobdiff