mirror of
https://github.com/systemd/systemd.git
synced 2024-11-02 02:21:44 +03:00
226 lines
9.9 KiB
XML
226 lines
9.9 KiB
XML
<?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-nspawn">
|
|
|
|
<refentryinfo>
|
|
<title>systemd-nspawn</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-nspawn</refentrytitle>
|
|
<manvolnum>1</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>systemd-nspawn</refname>
|
|
<refpurpose>Spawn a namespace container for debugging, testing and building</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<cmdsynopsis>
|
|
<command>systemd-nspawn <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt">COMMAND</arg> <arg choice="opt" rep="repeat">ARGS</arg></command>
|
|
</cmdsynopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para><command>systemd-nspawn</command> may be used to
|
|
run a command or OS in a light-weight namespace
|
|
container. In many ways it is similar to
|
|
<citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
|
but more powerful since it fully virtualizes the file
|
|
system hierarchy, as well as the process tree, the
|
|
various IPC subsystems and the host and domain
|
|
name.</para>
|
|
|
|
<para><command>systemd-nspawn</command> limits access
|
|
to various kernel interfaces in the container to
|
|
read-only, such as <filename>/sys</filename>,
|
|
<filename>/proc/sys</filename> or
|
|
<filename>/sys/fs/selinux</filename>. Network
|
|
interfaces and the system clock may not be changed
|
|
from within the container. Device nodes may not be
|
|
created. The host system cannot be rebooted and kernel
|
|
modules may not be loaded from within the
|
|
container.</para>
|
|
|
|
<para>Note that even though these security precautions
|
|
are taken <command>systemd-nspawn</command> is not
|
|
suitable for secure container setups. Many of the
|
|
security features may be circumvented and are hence
|
|
primarily useful to avoid accidental changes to the
|
|
host system from the container. The intended use of
|
|
this program is debugging and testing as well as
|
|
building of packages, distributions and software
|
|
involved with boot and systems management.</para>
|
|
|
|
<para>In contrast to
|
|
<citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
<command>systemd-nspawn</command> may be used to boot
|
|
full Linux-based operating systems in a
|
|
container.</para>
|
|
|
|
<para>Use a tool like
|
|
<citerefentry><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry> or <citerefentry><refentrytitle>mock</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
to set up an OS directory tree suitable as file system
|
|
hierarchy for <command>systemd-nspawn</command> containers.</para>
|
|
|
|
<para>Note that <command>systemd-nspawn</command> will
|
|
mount file systems private to the container to
|
|
<filename>/dev</filename>,
|
|
<filename>/run</filename> and similar. These will
|
|
not be visible outside of the container, and their
|
|
contents will be lost when the container exits.</para>
|
|
|
|
<para>Note that running two
|
|
<command>systemd-nspawn</command> containers from the
|
|
same directory tree will not make processes in them
|
|
see each other. The PID namespace separation of the
|
|
two containers is complete and the containers will
|
|
share very few runtime objects except for the
|
|
underlying file system.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Options</title>
|
|
|
|
<para>If no arguments are passed the container is set
|
|
up and a shell started in it, otherwise the passed
|
|
command and arguments are executed in it. The
|
|
following options are understood:</para>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><option>--help</option></term>
|
|
<term><option>-h</option></term>
|
|
|
|
<listitem><para>Prints a short help
|
|
text and exits.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--directory=</option></term>
|
|
<term><option>-D</option></term>
|
|
|
|
<listitem><para>Directory to use as
|
|
file system root for the namespace
|
|
container. If omitted the current
|
|
directory will be
|
|
used.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--user=</option></term>
|
|
<term><option>-u</option></term>
|
|
|
|
<listitem><para>Run the command
|
|
under specified user, create home
|
|
directory and cd into it. As rest
|
|
of systemd-nspawn, this is not
|
|
the security feature and limits
|
|
against accidental changes only.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--controllers=</option></term>
|
|
<term><option>-C</option></term>
|
|
|
|
<listitem><para>Makes the container appear in
|
|
other hierarchies that the name=systemd:/ one.
|
|
Takes a comma-separated list of controllers.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--private-network</option></term>
|
|
|
|
<listitem><para>Turn off networking in
|
|
the container. This makes all network
|
|
interfaces unavailable in the
|
|
container, with the exception of the
|
|
loopback device.</para></listitem>
|
|
</varlistentry>
|
|
|
|
</variablelist>
|
|
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Example 1</title>
|
|
|
|
<programlisting># debootstrap --arch=amd64 unstable debian-tree/
|
|
# systemd-nspawn -D debian-tree/</programlisting>
|
|
|
|
<para>This installs a minimal Debian unstable
|
|
distribution into the directory
|
|
<filename>debian-tree/</filename> and then spawns a
|
|
shell in a namespace container in it.</para>
|
|
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Example 2</title>
|
|
|
|
<programlisting># mock --init
|
|
# systemd-nspawn -D /var/lib/mock/fedora-rawhide-x86_64/root/ /sbin/init systemd.log_level=debug</programlisting>
|
|
|
|
<para>This installs a minimal Fedora distribution into
|
|
a subdirectory of <filename>/var/lib/mock/</filename>
|
|
and then boots an OS in a namespace container in it,
|
|
with systemd as init system, configured for debug
|
|
logging.</para>
|
|
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Exit status</title>
|
|
|
|
<para>The exit code of the program executed in the
|
|
container is returned.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>mock</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
|
|
</refentry>
|