1
0
mirror of https://github.com/systemd/systemd.git synced 2024-11-01 09:21:26 +03:00
systemd/man/systemd-run.xml
Lennart Poettering 450442cf93 add a new tool for creating transient mount and automount units
This adds "systemd-mount" which is for transient mount and automount units what
"systemd-run" is for transient service, scope and timer units.

The tool allows establishing mounts and automounts during runtime. It is very
similar to the usual /bin/mount commands, but can pull in additional
dependenices on access (for example, it pulls in fsck automatically), an take
benefit of the automount logic.

This tool is particularly useful for mount removable file systems (such as USB
sticks), as the automount logic (together with automatic unmount-on-idle), as
well as automatic fsck on first access ensure that the removable file system
has a high chance to remain in a fully clean state even when it is unplugged
abruptly, and returns to a clean state on the next re-plug.

This is a follow-up for #2471, as it adds a simple client-side for the
transient automount logic added in that PR.

In later work it might make sense to invoke this tool automatically from udev
rules in order to implement a simpler and safer version of removable media
management á la udisks.
2016-08-18 22:41:19 +02:00

461 lines
19 KiB
XML

<?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 2013 Zbigniew Jędrzejewski-Szmek
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-run"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-run</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-run</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-run</refname>
<refpurpose>Run programs in transient scope units, service units, or timer-scheduled service units</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>systemd-run</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="plain"><replaceable>COMMAND</replaceable>
<arg choice="opt" rep="repeat">ARGS</arg>
</arg>
</cmdsynopsis>
<cmdsynopsis>
<command>systemd-run</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="opt" rep="repeat">TIMER OPTIONS</arg>
<arg choice="req"><replaceable>COMMAND</replaceable></arg>
<arg choice="opt" rep="repeat">ARGS</arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>systemd-run</command> may be used to create and
start a transient <filename>.service</filename> or
<filename>.scope</filename> unit and run the specified
<replaceable>COMMAND</replaceable> in it. It may also be used to
create and start transient <filename>.timer</filename>
units.</para>
<para>If a command is run as transient service unit, it will be
started and managed by the service manager like any other service,
and thus shows up in the output of <command>systemctl
list-units</command> like any other unit. It will run in a clean
and detached execution environment, with the service manager as
its parent process. In this mode, <command>systemd-run</command>
will start the service asynchronously in the background and return
after the command has begun execution.</para>
<para>If a command is run as transient scope unit, it will be
started by <command>systemd-run</command> itself as parent process
and will thus inherit the execution environment of the
caller. However, the processes of the command are managed by the
service manager similar to normal services, and will show up in
the output of <command>systemctl list-units</command>. Execution
in this case is synchronous, and will return only when the command
finishes. This mode is enabled via the <option>--scope</option>
switch (see below). </para>
<para>If a command is run with timer options such as
<option>--on-calendar=</option> (see below), a transient timer
unit is created alongside the service unit for the specified
command. Only the transient timer unit is started immediately, the
transient service unit will be started when the transient timer
elapses. If the <option>--unit=</option> is specified, the
<replaceable>COMMAND</replaceable> may be omitted. In this case,
<command>systemd-run</command> only creates a
<filename>.timer</filename> unit that invokes the specified unit
when elapsing.</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<varlistentry>
<term><option>--no-ask-password</option></term>
<listitem><para>Do not query the user for authentication for
privileged operations.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--scope</option></term>
<listitem>
<para>Create a transient <filename>.scope</filename> unit instead of
the default transient <filename>.service</filename> unit.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--unit=</option></term>
<listitem><para>Use this unit name instead of an automatically
generated one.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--property=</option></term>
<term><option>-p</option></term>
<listitem><para>Sets a unit property for the scope or service
unit that is created. This takes an assignment in the same
format as
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<command>set-property</command> command.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--description=</option></term>
<listitem><para>Provide a description for the service or scope
unit. If not specified, the command itself will be used as a
description. See <varname>Description=</varname> in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--slice=</option></term>
<listitem><para>Make the new <filename>.service</filename> or
<filename>.scope</filename> unit part of the specified slice,
instead of the <filename>system.slice</filename>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--remain-after-exit</option></term>
<listitem><para>After the service or scope process has
terminated, keep the service around until it is explicitly
stopped. This is useful to collect runtime information about
the service after it finished running. Also see
<varname>RemainAfterExit=</varname> in
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--send-sighup</option></term>
<listitem><para>When terminating the scope or service unit,
send a SIGHUP immediately after SIGTERM. This is useful to
indicate to shells and shell-like processes that the
connection has been severed. Also see
<varname>SendSIGHUP=</varname> in
<citerefentry><refentrytitle>systemd.kill</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--service-type=</option></term>
<listitem><para>Sets the service type. Also see
<varname>Type=</varname> in
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>. This
option has no effect in conjunction with
<option>--scope</option>. Defaults to
<constant>simple</constant>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--uid=</option></term>
<term><option>--gid=</option></term>
<listitem><para>Runs the service process under the UNIX user
and group. Also see <varname>User=</varname> and
<varname>Group=</varname> in
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--nice=</option></term>
<listitem><para>Runs the service process with the specified
nice level. Also see <varname>Nice=</varname> in
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-E <replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term>
<term><option>--setenv=<replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term>
<listitem><para>Runs the service process with the specified environment variable set.
Also see <varname>Environment=</varname> in
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--pty</option></term>
<term><option>-t</option></term>
<listitem><para>When invoking a command, the service connects
its standard input and output to the invoking tty via a
pseudo TTY device. This allows invoking binaries as services
that expect interactive user input, such as interactive
command shells.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--quiet</option></term>
<term><option>-q</option></term>
<listitem><para>Suppresses additional informational output
while running. This is particularly useful in combination with
<option>--pty</option> when it will suppress the initial
message explaining how to terminate the TTY connection.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--on-active=</option></term>
<term><option>--on-boot=</option></term>
<term><option>--on-startup=</option></term>
<term><option>--on-unit-active=</option></term>
<term><option>--on-unit-inactive=</option></term>
<listitem><para>Defines monotonic timers relative to different
starting points. Also see <varname>OnActiveSec=</varname>,
<varname>OnBootSec=</varname>,
<varname>OnStartupSec=</varname>,
<varname>OnUnitActiveSec=</varname> and
<varname>OnUnitInactiveSec=</varname> in
<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>. This
options have no effect in conjunction with
<option>--scope</option>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--on-calendar=</option></term>
<listitem><para>Defines realtime (i.e. wallclock) timers with
calendar event expressions. Also see
<varname>OnCalendar=</varname> in
<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>. This
option has no effect in conjunction with
<option>--scope</option>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--timer-property=</option></term>
<listitem><para>Sets a timer unit property for the timer unit
that is created. It is similar with
<option>--property</option> but only for created timer
unit. This option only has effect in conjunction with
<option>--on-active=</option>, <option>--on-boot=</option>,
<option>--on-startup=</option>,
<option>--on-unit-active=</option>,
<option>--on-unit-inactive=</option>,
<option>--on-calendar=</option>. This takes an assignment in
the same format as
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<command>set-property</command> command.</para> </listitem>
</varlistentry>
<varlistentry>
<term><option>--no-block</option></term>
<listitem>
<para>Do not synchronously wait for the requested operation
to finish. If this is not specified, the job will be
verified, enqueued and <command>systemd-run</command> will
wait until the unit's start-up is completed. By passing this
argument, it is only verified and enqueued.</para>
</listitem>
</varlistentry>
<xi:include href="user-system-options.xml" xpointer="user" />
<xi:include href="user-system-options.xml" xpointer="system" />
<xi:include href="user-system-options.xml" xpointer="host" />
<xi:include href="user-system-options.xml" xpointer="machine" />
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
<para>All command line arguments after the first non-option
argument become part of the command line of the launched
process. If a command is run as service unit, its first argument
needs to be an absolute binary path.</para>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, a non-zero failure
code otherwise.</para>
</refsect1>
<refsect1>
<title>Examples</title>
<example>
<title>Logging environment variables provided by systemd to services</title>
<programlisting># systemd-run env
Running as unit: run-19945.service
# journalctl -u run-19945.service
Sep 08 07:37:21 bupkis systemd[1]: Starting /usr/bin/env...
Sep 08 07:37:21 bupkis systemd[1]: Started /usr/bin/env.
Sep 08 07:37:21 bupkis env[19948]: PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
Sep 08 07:37:21 bupkis env[19948]: LANG=en_US.UTF-8
Sep 08 07:37:21 bupkis env[19948]: BOOT_IMAGE=/vmlinuz-3.11.0-0.rc5.git6.2.fc20.x86_64</programlisting>
</example>
<example>
<title>Limiting resources available to a command</title>
<programlisting># systemd-run -p BlockIOWeight=10 updatedb</programlisting>
<para>This command invokes the
<citerefentry project='man-pages'><refentrytitle>updatedb</refentrytitle><manvolnum>8</manvolnum></citerefentry>
tool, but lowers the block I/O weight for it to 10. See
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>
for more information on the <varname>BlockIOWeight=</varname>
property.</para>
</example>
<example>
<title>Running commands at a specified time</title>
<para>The following command will touch a file after 30 seconds.</para>
<programlisting># date; systemd-run --on-active=30 --timer-property=AccuracySec=100ms /bin/touch /tmp/foo
Mon Dec 8 20:44:24 KST 2014
Running as unit: run-71.timer
Will run service as unit: run-71.service
# journalctl -b -u run-71.timer
-- Logs begin at Fri 2014-12-05 19:09:21 KST, end at Mon 2014-12-08 20:44:54 KST. --
Dec 08 20:44:38 container systemd[1]: Starting /bin/touch /tmp/foo.
Dec 08 20:44:38 container systemd[1]: Started /bin/touch /tmp/foo.
# journalctl -b -u run-71.service
-- Logs begin at Fri 2014-12-05 19:09:21 KST, end at Mon 2014-12-08 20:44:54 KST. --
Dec 08 20:44:48 container systemd[1]: Starting /bin/touch /tmp/foo...
Dec 08 20:44:48 container systemd[1]: Started /bin/touch /tmp/foo.</programlisting>
</example>
<example>
<title>Allowing access to the tty</title>
<para>The following command invokes <filename>/bin/bash</filename> as a service
passing its standard input, output and error to the calling TTY.</para>
<programlisting># systemd-run -t --send-sighup /bin/bash</programlisting>
</example>
<example>
<title>Start <command>screen</command> as a user service</title>
<programlisting>$ systemd-run --scope --user screen
Running scope as unit run-r14b0047ab6df45bfb45e7786cc839e76.scope.
$ screen -ls
There is a screen on:
492..laptop (Detached)
1 Socket in /var/run/screen/S-fatima.
</programlisting>
<para>This starts the <command>screen</command> process as a child of the
<command>systemd --user</command> process that was started by
<filename>user@.service</filename>, in a scope unit. A
<citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>
unit is used instead of a
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
unit, because <command>screen</command> will exit when detaching from the terminal,
and a service unit would be terminated. Running <command>screen</command>
as a user unit has the advantage that it is not part of the session scope.
If <varname>KillUserProcesses=yes</varname> is configured in
<citerefentry><refentrytitle>logind.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
the default, the session scope will be terminated when the user logs
out of that session.</para>
<para>The <filename>user@.service</filename> is started automatically
when the user first logs in, and stays around as long as at least one
login session is open. After the user logs out of the last session,
<filename>user@.service</filename> and all services underneath it
are terminated. This behaviour is the default, when "lingering" is
not enabled for that user. Enabling lingering means that
<filename>user@.service</filename> is started automatically during
boot, even if the user is not logged in, and that the service is
not terminated when the user logs out.</para>
<para>Enabling lingering allows the user to run processes without being logged in,
for example to allow <command>screen</command> to persist after the user logs out,
even if the session scope is terminated. In the default configuration, users can
enable lingering for themselves:</para>
<programlisting>$ loginctl enable-linger</programlisting>
</example>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.scope</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-mount</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>