shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2024-11-01 00:51:24 +03:00
Code
130298ba10
systemd/man/systemd-nspawn.xml

1735 lines
103 KiB
XML
Raw Normal View History

man: drop mode line in file headers This is already included in .dir-locals, so we don't need it in the files themselves.
2018-07-03 00:15:39 +03:00
<?xml version='1.0'?>
man: use same header for all files The "include" files had type "book" for some raeason. I don't think this is meaningful. Let's just use the same everywhere. $ perl -i -0pe 's^..DOCTYPE (book|refentry) PUBLIC "-//OASIS//DTD DocBook XML V4.[25]//EN"\s+"http^<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"\n "http^gms' man/*.xml
2019-03-14 16:40:58 +03:00
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
man: use entities for fedora number and update URL Fedora 28 is out already, let's advertise it. While at it, drop "container" from "f28container" — it's a subdirectory under /var/lib/machines, it's pretty obvious that's it a container. To make the switch easier in the future, define the number as an entity.
2018-06-05 10:15:19 +03:00
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [
man/machinectl: fix pull-raw example We do not allow machine names with "_", so the command would fail as written. Share the example with the systemd-nspawn page instead.
2020-10-27 18:01:16 +03:00
<!ENTITY % entities SYSTEM "custom-entities.ent" >
%entities;
man: use entities for fedora number and update URL Fedora 28 is out already, let's advertise it. While at it, drop "container" from "f28container" — it's a subdirectory under /var/lib/machines, it's pretty obvious that's it a container. To make the switch easier in the future, define the number as an entity.
2018-06-05 10:15:19 +03:00
]>
license: LGPL-2.1+ -> LGPL-2.1-or-later
2020-11-09 07:23:58 +03:00
<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
man: xinclude --help/--version/--no-pager
2014-02-13 23:33:51 +04:00
<refentry id="systemd-nspawn"
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-nspawn</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-nspawn</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-nspawn</refname>
summary: update nspawn description string a bit nspawn as it is now is a generally useful tool, hence let's drop the comments about it being useful for debug and so on only. The new wording just makes the first sentence of the main page also the summary.
2018-06-27 20:59:45 +03:00
<refpurpose>Spawn a command or OS in a light-weight container</refpurpose>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>systemd-nspawn</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="opt"><replaceable>COMMAND</replaceable>
<arg choice="opt" rep="repeat">ARGS</arg>
</arg>
</cmdsynopsis>
<cmdsynopsis>
<command>systemd-nspawn</command>
man: minor nspawn doc fixes
2016-02-24 16:08:53 +03:00
<arg choice="plain">--boot</arg>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="opt" rep="repeat">ARGS</arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<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
project='man-pages'><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>
man: make chroot less prominent in discussion of nspawn Not as many people use chroot as before, so make the flow a bit nicer by talking less about chroot. "change to the either" is awkward and unclear. Just remove that part, because all changes are lost, period.
2016-07-22 23:31:55 +03:00
<para><command>systemd-nspawn</command> may be invoked on any directory tree containing an operating system tree,
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
using the <option>--directory=</option> command line option. By using the <option>--machine=</option> option an OS
man: make chroot less prominent in discussion of nspawn Not as many people use chroot as before, so make the flow a bit nicer by talking less about chroot. "change to the either" is awkward and unclear. Just remove that part, because all changes are lost, period.
2016-07-22 23:31:55 +03:00
tree is automatically searched for in a couple of locations, most importantly in
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
<filename>/var/lib/machines/</filename>, the suggested directory to place OS container images installed on the
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
system.</para>
<para>In contrast to <citerefentry
project='man-pages'><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><command>systemd-nspawn</command> limits access to various kernel interfaces in the container to read-only,
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
such as <filename>/sys/</filename>, <filename>/proc/sys/</filename> or <filename>/sys/fs/selinux/</filename>. The
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
host's 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
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
container.</para>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<para>Use a tool like <citerefentry
project='mankier'><refentrytitle>dnf</refentrytitle><manvolnum>8</manvolnum></citerefentry>, <citerefentry
project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>, or
<citerefentry project='archlinux'><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry> to
set up an OS directory tree suitable as file system hierarchy for <command>systemd-nspawn</command> containers. See
the Examples section below for details on suitable invocation of these commands.</para>
<para>As a safety check <command>systemd-nspawn</command> will verify the existence of
<filename>/usr/lib/os-release</filename> or <filename>/etc/os-release</filename> in the container tree before
starting the container (see
<citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>). It might be
necessary to add this file to the container tree manually if the OS of the container is too old to contain this
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
file out-of-the-box.</para>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<para><command>systemd-nspawn</command> may be invoked directly from the interactive command line or run as system
service in the background. In this mode each container instance runs as its own service instance; a default
template unit file <filename>systemd-nspawn@.service</filename> is provided to make this easy, taking the container
name as instance identifier. Note that different default options apply when <command>systemd-nspawn</command> is
treewide: fix typos
2016-05-12 12:23:35 +03:00
invoked by the template unit file than interactively on the command line. Most importantly the template unit file
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
makes use of the <option>--boot</option> which is not the default in case <command>systemd-nspawn</command> is
treewide: fix typos
2016-05-12 12:23:35 +03:00
invoked from the interactive command line. Further differences with the defaults are documented along with the
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
various supported options below.</para>
<para>The <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> tool may
be used to execute a number of operations on containers. In particular it provides easy-to-use commands to run
containers as system services using the <filename>systemd-nspawn@.service</filename> template unit
file.</para>
<para>Along with each container a settings file with the <filename>.nspawn</filename> suffix may exist, containing
additional settings to apply when running the container. See
<citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
details. Settings files override the default options used by the <filename>systemd-nspawn@.service</filename>
template unit file, making it usually unnecessary to alter this template file directly.</para>
<para>Note that <command>systemd-nspawn</command> will mount file systems private to the container to
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
<filename>/dev/</filename>, <filename>/run/</filename> and similar. These will not be visible outside of the
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
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. Use
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>'s
<command>login</command> or <command>shell</command> commands to request an additional login session in a running
container.</para>
<para><command>systemd-nspawn</command> implements the <ulink
man: change links to container interface doc to https://systemd.io/ Now that we converted the documentation we should also link to it.
2020-01-06 20:15:07 +03:00
url="https://systemd.io/CONTAINER_INTERFACE">Container Interface</ulink> specification.</para>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<para>While running, containers invoked with <command>systemd-nspawn</command> are registered with the
<citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry> service that
keeps track of running containers, and provides programming interfaces to interact with them.</para>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</refsect1>
<refsect1>
<title>Options</title>
<para>If option <option>-b</option> is specified, the arguments
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
are used as arguments for the init program. Otherwise,
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<replaceable>COMMAND</replaceable> specifies the program to launch
in the container, and the remaining arguments are used as
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
arguments for this program. If <option>--boot</option> is not used and
treewide: Correct typos and spell plural of bus consistent
2015-05-11 14:49:29 +03:00
no arguments are specified, a shell is launched in the
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
container.</para>
<para>The following options are understood:</para>
<variablelist>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>-q</option></term>
<term><option>--quiet</option></term>
<listitem><para>Turns off any status output by the tool
itself. When this switch is used, the only output from nspawn
will be the console output of the container OS
itself.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--settings=</option><replaceable>MODE</replaceable></term>
<listitem><para>Controls whether
<command>systemd-nspawn</command> shall search for and use
additional per-container settings from
<filename>.nspawn</filename> files. Takes a boolean or the
special values <option>override</option> or
<option>trusted</option>.</para>
<para>If enabled (the default), a settings file named after the
machine (as specified with the <option>--machine=</option>
setting, or derived from the directory or image file name)
with the suffix <filename>.nspawn</filename> is searched in
<filename>/etc/systemd/nspawn/</filename> and
<filename>/run/systemd/nspawn/</filename>. If it is found
there, its settings are read and used. If it is not found
there, it is subsequently searched in the same directory as the
image file or in the immediate parent of the root directory of
the container. In this case, if the file is found, its settings
will be also read and used, but potentially unsafe settings
are ignored. Note that in both these cases, settings on the
command line take precedence over the corresponding settings
from loaded <filename>.nspawn</filename> files, if both are
specified. Unsafe settings are considered all settings that
elevate the container's privileges or grant access to
additional resources such as files or directories of the
host. For details about the format and contents of
<filename>.nspawn</filename> files, consult
<citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
<para>If this option is set to <option>override</option>, the
file is searched, read and used the same way, however, the order of
precedence is reversed: settings read from the
<filename>.nspawn</filename> file will take precedence over
the corresponding command line options, if both are
specified.</para>
<para>If this option is set to <option>trusted</option>, the
file is searched, read and used the same way, but regardless
of being found in <filename>/etc/systemd/nspawn/</filename>,
<filename>/run/systemd/nspawn/</filename> or next to the image
file or container root directory, all settings will take
effect, however, command line arguments still take precedence
over corresponding settings.</para>
<para>If disabled, no <filename>.nspawn</filename> file is read
and no settings except the ones on the command line are in
effect.</para></listitem>
</varlistentry>
</variablelist>
<refsect2>
<title>Image Options</title>
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>-D</option></term>
<term><option>--directory=</option></term>
<listitem><para>Directory to use as file system root for the
container.</para>
<para>If neither <option>--directory=</option>, nor
<option>--image=</option> is specified the directory is
man: point nspawn --machine to machinectl search-path The --machine option used to describe searching for machines in /var/lib/machines, which is not the whole story, so let's link to where it's described in more detail.
2015-08-05 11:40:36 +03:00
determined by searching for a directory named the same as the
machine name specified with <option>--machine=</option>. See
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
section "Files and Directories" for the precise search path.</para>
<para>If neither <option>--directory=</option>,
<option>--image=</option>, nor <option>--machine=</option>
are specified, the current directory will
be used. May not be specified together with
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<option>--image=</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--template=</option></term>
man: document that --ephemeral and --template= don't cover submounts We never made this clear, let's fix that.
2019-03-01 17:14:36 +03:00
<listitem><para>Directory or <literal>btrfs</literal> subvolume to use as template for the
container's root directory. If this is specified and the container's root directory (as configured by
<option>--directory=</option>) does not yet exist it is created as <literal>btrfs</literal> snapshot
(if supported) or plain directory (otherwise) and populated from this template tree. Ideally, the
specified template path refers to the root of a <literal>btrfs</literal> subvolume, in which case a
simple copy-on-write snapshot is taken, and populating the root directory is instant. If the
specified template path does not refer to the root of a <literal>btrfs</literal> subvolume (or not
even to a <literal>btrfs</literal> file system at all), the tree is copied (though possibly in a
'reflink' copy-on-write scheme — if the file system supports that), which can be substantially more
time-consuming. Note that the snapshot taken is of the specified directory or subvolume, including
all subdirectories and subvolumes below it, but excluding any sub-mounts. May not be specified
together with <option>--image=</option> or <option>--ephemeral</option>.</para>
man: document that nspawn -x, --template= and machinectl clone leave hostname and machine id unmodified
2015-05-05 23:48:28 +03:00
tree-wide: use "hostname" spelling everywhere It's not that I think that "hostname" is vastly superior to "host name". Quite the opposite — the difference is small, and in some context the two-word version does fit better. But in the tree, there are ~200 occurrences of the first, and >1600 of the other, and consistent spelling is more important than any particular spelling choice.
2020-04-14 11:37:40 +03:00
<para>Note that this switch leaves hostname, machine ID and
man: document that nspawn -x, --template= and machinectl clone leave hostname and machine id unmodified
2015-05-05 23:48:28 +03:00
all other settings that could identify the instance
unmodified.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>-x</option></term>
<term><option>--ephemeral</option></term>
nspawn: support ephemeral boots from images Previously --ephemeral was only supported with container trees in btrfs subvolumes (i.e. in combination with --directory=). This adds support for --ephemeral in conjunction with disk images (i.e. --image=) too. As side effect this fixes that --ephemeral was accepted but ignored when using -M on a container that turned out to be an image. Fixes: #4664
2016-11-18 20:38:06 +03:00
<listitem><para>If specified, the container is run with a temporary snapshot of its file system that is removed
immediately when the container terminates. May not be specified together with
man: document that nspawn -x, --template= and machinectl clone leave hostname and machine id unmodified
2015-05-05 23:48:28 +03:00
<option>--template=</option>.</para>
tree-wide: use "hostname" spelling everywhere It's not that I think that "hostname" is vastly superior to "host name". Quite the opposite — the difference is small, and in some context the two-word version does fit better. But in the tree, there are ~200 occurrences of the first, and >1600 of the other, and consistent spelling is more important than any particular spelling choice.
2020-04-14 11:37:40 +03:00
<para>Note that this switch leaves hostname, machine ID and all other settings that could identify
man: document that --ephemeral and --template= don't cover submounts We never made this clear, let's fix that.
2019-03-01 17:14:36 +03:00
the instance unmodified. Please note that — as with <option>--template=</option> — taking the
temporary snapshot is more efficient on file systems that support subvolume snapshots or 'reflinks'
natively (<literal>btrfs</literal> or new <literal>xfs</literal>) than on more traditional file
systems that do not (<literal>ext4</literal>). Note that the snapshot taken is of the specified
directory or subvolume, including all subdirectories and subvolumes below it, but excluding any
sub-mounts.</para>
man: document nspawn's new --volatile=overlay switch
2018-12-21 23:45:46 +03:00
<para>With this option no modifications of the container image are retained. Use
<option>--volatile=</option> (described below) for other mechanisms to restrict persistency of
container images during runtime.</para>
</listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>-i</option></term>
<term><option>--image=</option></term>
<listitem><para>Disk image to mount the root directory for the
container from. Takes a path to a regular file or to a block
device node. The file or block device must contain
either:</para>
<itemizedlist>
<listitem><para>An MBR partition table with a single
partition of type 0x83 that is marked
bootable.</para></listitem>
<listitem><para>A GUID partition table (GPT) with a single
partition of type
0fc63daf-8483-4772-8e79-3d69d8477de4.</para></listitem>
<listitem><para>A GUID partition table (GPT) with a marked
root partition which is mounted as the root directory of the
container. Optionally, GPT images may contain a home and/or
a server data partition which are mounted to the appropriate
places in the container. All these partitions must be
identified by the partition types defined by the <ulink
docs: import discoverable partitions spec This was previously available here: https://www.freedesktop.org/wiki/Specifications/DiscoverablePartitionsSpec/ Let's pull it into our repository.
2019-12-19 11:27:10 +03:00
url="https://systemd.io/DISCOVERABLE_PARTITIONS">Discoverable
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
Partitions Specification</ulink>.</para></listitem>
man: update the nspawn man page, and document what kind of dissection features we now support
2016-12-07 20:36:08 +03:00
<listitem><para>No partition table, and a single file system spanning the whole image.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</itemizedlist>
nspawn: support ephemeral boots from images Previously --ephemeral was only supported with container trees in btrfs subvolumes (i.e. in combination with --directory=). This adds support for --ephemeral in conjunction with disk images (i.e. --image=) too. As side effect this fixes that --ephemeral was accepted but ignored when using -M on a container that turned out to be an image. Fixes: #4664
2016-11-18 20:38:06 +03:00
<para>On GPT images, if an EFI System Partition (ESP) is discovered, it is automatically mounted to
<filename>/efi</filename> (or <filename>/boot</filename> as fallback) in case a directory by this name exists
and is empty.</para>
man: update the nspawn man page, and document what kind of dissection features we now support
2016-12-07 20:36:08 +03:00
<para>Partitions encrypted with LUKS are automatically decrypted. Also, on GPT images dm-verity data integrity
hash partitions are set up if the root hash for them is specified using the <option>--root-hash=</option>
option.</para>
dissect: support single-filesystem verity images with external verity hash dm-verity support in dissect-image at the moment is restricted to GPT volumes. If the image a single-filesystem type without a partition table (eg: squashfs) and a roothash/verity file are passed, set the verity flag and mark as read-only.
2020-05-29 19:51:20 +03:00
<para>Single file system images (i.e. file systems without a surrounding partition table) can be opened using
dm-verity if the integrity data is passed using the <option>--root-hash=</option> and
dissect/nspawn: add support for dm-verity root hash signature Since cryptsetup 2.3.0 a new API to verify dm-verity volumes by a pkcs7 signature, with the public key in the kernel keyring, is available. Use it if libcryptsetup supports it.
2020-06-02 17:35:58 +03:00
<option>--verity-data=</option> (and optionally <option>--root-hash-sig=</option>) options.</para>
dissect: support single-filesystem verity images with external verity hash dm-verity support in dissect-image at the moment is restricted to GPT volumes. If the image a single-filesystem type without a partition table (eg: squashfs) and a roothash/verity file are passed, set the verity flag and mark as read-only.
2020-05-29 19:51:20 +03:00
nspawn: support ephemeral boots from images Previously --ephemeral was only supported with container trees in btrfs subvolumes (i.e. in combination with --directory=). This adds support for --ephemeral in conjunction with disk images (i.e. --image=) too. As side effect this fixes that --ephemeral was accepted but ignored when using -M on a container that turned out to be an image. Fixes: #4664
2016-11-18 20:38:06 +03:00
<para>Any other partitions, such as foreign partitions or swap partitions are not mounted. May not be specified
together with <option>--directory=</option>, <option>--template=</option>.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: update the nspawn man page, and document what kind of dissection features we now support
2016-12-07 20:36:08 +03:00
man: document the various new options nspawn learnt
2018-07-31 14:18:55 +03:00
<varlistentry>
<term><option>--oci-bundle=</option></term>
<listitem><para>Takes the path to an OCI runtime bundle to invoke, as specified in the <ulink
url="https://github.com/opencontainers/runtime-spec/blob/master/spec.md">OCI Runtime Specification</ulink>. In
this case no <filename>.nspawn</filename> file is loaded, and the root directory and various settings are read
from the OCI runtime JSON data (but data passed on the command line takes precedence).</para></listitem>
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>--read-only</option></term>
<listitem><para>Mount the container's root file system (and any other file systems container in the container
image) read-only. This has no effect on additional mounts made with <option>--bind=</option>,
<option>--tmpfs=</option> and similar options. This mode is implied if the container image file or directory is
marked read-only itself. It is also implied if <option>--volatile=</option> is used. In this case the container
image on disk is strictly read-only, while changes are permitted but kept non-persistently in memory only. For
further details, see below.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--volatile</option></term>
<term><option>--volatile=</option><replaceable>MODE</replaceable></term>
<listitem><para>Boots the container in volatile mode. When no mode parameter is passed or when mode is
specified as <option>yes</option>, full volatile mode is enabled. This means the root directory is mounted as a
mostly unpopulated <literal>tmpfs</literal> instance, and <filename>/usr/</filename> from the OS tree is
mounted into it in read-only mode (the system thus starts up with read-only OS image, but pristine state and
configuration, any changes are lost on shutdown). When the mode parameter is specified as
<option>state</option>, the OS tree is mounted read-only, but <filename>/var/</filename> is mounted as a
writable <literal>tmpfs</literal> instance into it (the system thus starts up with read-only OS resources and
configuration, but pristine state, and any changes to the latter are lost on shutdown). When the mode parameter
is specified as <option>overlay</option> the read-only root file system is combined with a writable
<filename>tmpfs</filename> instance through <literal>overlayfs</literal>, so that it appears at it normally
would, but any changes are applied to the temporary file system only and lost when the container is
terminated. When the mode parameter is specified as <option>no</option> (the default), the whole OS tree is
made available writable (unless <option>--read-only</option> is specified, see above).</para>
man: do not index various /foobar/ paths For #17177.
2020-09-29 11:04:12 +03:00
<para>Note that if one of the volatile modes is chosen, its effect is limited to the root file system
(or <filename>/var/</filename> in case of <option>state</option>), and any other mounts placed in the
hierarchy are unaffected — regardless if they are established automatically (e.g. the EFI system
partition that might be mounted to <filename>/efi/</filename> or <filename>/boot/</filename>) or
explicitly (e.g. through an additional command line option such as <option>--bind=</option>, see
below). This means, even if <option>--volatile=overlay</option> is used changes to
<filename>/efi/</filename> or <filename>/boot/</filename> are prohibited in case such a partition
exists in the container image operated on, and even if <option>--volatile=state</option> is used the
hypothetical file <filename index="false">/etc/foobar</filename> is potentially writable if
<option>--bind=/etc/foobar</option> if used to mount it from outside the read-only container
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
<filename>/etc/</filename> directory.</para>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<para>The <option>--ephemeral</option> option is closely related to this setting, and provides similar
behaviour by making a temporary, ephemeral copy of the whole OS image and executing that. For further details,
see above.</para>
<para>The <option>--tmpfs=</option> and <option>--overlay=</option> options provide similar functionality, but
for specific sub-directories of the OS image only. For details, see below.</para>
<para>This option provides similar functionality for containers as the <literal>systemd.volatile=</literal>
kernel command line switch provides for host systems. See
<citerefentry><refentrytitle>kernel-command-line</refentrytitle><manvolnum>7</manvolnum></citerefentry> for
details.</para>
man: document that --volatile=yes is not supported for split /usr systems
2019-07-29 10:45:11 +03:00
<para>Note that setting this option to <option>yes</option> or <option>state</option> will only work
correctly with operating systems in the container that can boot up with only
<filename>/usr/</filename> mounted, and are able to automatically populate <filename>/var/</filename>
(and <filename>/etc/</filename> in case of <literal>--volatile=yes</literal>). Specifically, this
means that operating systems that follow the historic split of <filename>/bin/</filename> and
<filename>/lib/</filename> (and related directories) from <filename>/usr/</filename> (i.e. where the
former are not symlinks into the latter) are not supported by <literal>--volatile=yes</literal> as
container payload. The <option>overlay</option> option does not require any particular preparations
in the OS, but do note that <literal>overlayfs</literal> behaviour differs from regular file systems
in a number of ways, and hence compatibility is limited.</para></listitem>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</varlistentry>
man: update the nspawn man page, and document what kind of dissection features we now support
2016-12-07 20:36:08 +03:00
<varlistentry>
<term><option>--root-hash=</option></term>
<listitem><para>Takes a data integrity (dm-verity) root hash specified in hexadecimal. This option enables data
integrity checks using dm-verity, if the used image contains the appropriate integrity data (see above). The
man: add more commas for clarify and reword a few sentences
2017-02-09 06:53:16 +03:00
specified hash must match the root hash of integrity data, and is usually at least 256 bits (and hence 64
dissect: try to read roothash value off user.verity.roothash xattr of image file This slightly extends the roothash loading logic to first check for a user.verity.roothash extended attribute on the image file. If it exists, it is used as Verity root hash and the ".roothash" file is not used. This should improve the chance that the roothash is retained when the file is moved around, as the data snippet is attached directly to the image file. The field is still detached from the file payload however, in order to make sure it may be trusted independently. This does not replace the ".roothash" file loading, it simply adds a second way to retrieve the data. Extended attributes are often a poor choice for storing metadata like this as it is usually difficult to discover for admins and users, and hard to fix if it ever gets out of sync. However, in this case I think it's safe as verity implies read-only access, and thus there's little chance of it to get out of sync.
2016-12-23 19:38:12 +03:00
formatted hexadecimal characters) long (in case of SHA256 for example). If this option is not specified, but
the image file carries the <literal>user.verity.roothash</literal> extended file attribute (see <citerefentry
project='man-pages'><refentrytitle>xattr</refentrytitle><manvolnum>7</manvolnum></citerefentry>), then the root
hash is read from it, also as formatted hexadecimal characters. If the extended file attribute is not found (or
man: add more commas for clarify and reword a few sentences
2017-02-09 06:53:16 +03:00
is not supported by the underlying file system), but a file with the <filename>.roothash</filename> suffix is
dissect: support single-filesystem verity images with external verity hash dm-verity support in dissect-image at the moment is restricted to GPT volumes. If the image a single-filesystem type without a partition table (eg: squashfs) and a roothash/verity file are passed, set the verity flag and mark as read-only.
2020-05-29 19:51:20 +03:00
found next to the image file, bearing otherwise the same name (except if the image has the
<filename>.raw</filename> suffix, in which case the root hash file must not have it in its name), the root hash
doc: document the new GPT partition type UUIDs
2020-09-17 19:57:27 +03:00
is read from it and automatically used, also as formatted hexadecimal characters.</para>
<para>Note that this configures the root hash for the root file system. Disk images may also contain
separate file systems for the <filename>/usr/</filename> hierarchy, which may be Verity protected as
well. The root hash for this protection may be configured via the
<literal>user.verity.usrhash</literal> extended file attribute or via a <filename>.usrhash</filename>
file adjacent to the disk image, following the same format and logic as for the root hash for the
root file system described here. Note that there's currently no switch to configure the root hash for
man: in systemd-nspawn(1), refer to systemd.exec(5) for the shared stuff We should avoid duplicating lengthy description of very similar concepts. --root-hash-sig follows the same semantics as RootHashSig=, so just refer the reader to the other man page. --root-hash doesn't implement the same features as RootHash=, so we can't fully replace the description, but let's give the user a hint to look at the other man page too. For #17177.
2020-09-29 13:16:12 +03:00
the <filename>/usr/</filename> from the command line.</para>
<para>Also see the <varname>RootHash=</varname> option in
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
</listitem>
dissect: support single-filesystem verity images with external verity hash dm-verity support in dissect-image at the moment is restricted to GPT volumes. If the image a single-filesystem type without a partition table (eg: squashfs) and a roothash/verity file are passed, set the verity flag and mark as read-only.
2020-05-29 19:51:20 +03:00
</varlistentry>
dissect/nspawn: add support for dm-verity root hash signature Since cryptsetup 2.3.0 a new API to verify dm-verity volumes by a pkcs7 signature, with the public key in the kernel keyring, is available. Use it if libcryptsetup supports it.
2020-06-02 17:35:58 +03:00
<varlistentry>
<term><option>--root-hash-sig=</option></term>
man: in systemd-nspawn(1), refer to systemd.exec(5) for the shared stuff We should avoid duplicating lengthy description of very similar concepts. --root-hash-sig follows the same semantics as RootHashSig=, so just refer the reader to the other man page. --root-hash doesn't implement the same features as RootHash=, so we can't fully replace the description, but let's give the user a hint to look at the other man page too. For #17177.
2020-09-29 13:16:12 +03:00
<listitem><para>Takes a PKCS7 signature of the <option>--root-hash=</option> option.
The semantics are the same as for the <varname>RootHashSignature=</varname> option, see
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para></listitem>
dissect/nspawn: add support for dm-verity root hash signature Since cryptsetup 2.3.0 a new API to verify dm-verity volumes by a pkcs7 signature, with the public key in the kernel keyring, is available. Use it if libcryptsetup supports it.
2020-06-02 17:35:58 +03:00
</varlistentry>
dissect: support single-filesystem verity images with external verity hash dm-verity support in dissect-image at the moment is restricted to GPT volumes. If the image a single-filesystem type without a partition table (eg: squashfs) and a roothash/verity file are passed, set the verity flag and mark as read-only.
2020-05-29 19:51:20 +03:00
<varlistentry>
<term><option>--verity-data=</option></term>
<listitem><para>Takes the path to a data integrity (dm-verity) file. This option enables data integrity checks
using dm-verity, if a root-hash is passed and if the used image itself does not contains the integrity data.
The integrity data must be matched by the root hash. If this option is not specified, but a file with the
<filename>.verity</filename> suffix is found next to the image file, bearing otherwise the same name (except if
the image has the <filename>.raw</filename> suffix, in which case the verity data file must not have it in its name),
the verity data is read from it and automatically used.</para></listitem>
man: update the nspawn man page, and document what kind of dissection features we now support
2016-12-07 20:36:08 +03:00
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>--pivot-root=</option></term>
<listitem><para>Pivot the specified directory to <filename>/</filename> inside the container, and either unmount the
container's old root, or pivot it to another specified directory. Takes one of: a path argument — in which case the
specified path will be pivoted to <filename>/</filename> and the old root will be unmounted; or a colon-separated pair
of new root path and pivot destination for the old root. The new root path will be pivoted to <filename>/</filename>,
and the old <filename>/</filename> will be pivoted to the other directory. Both paths must be absolute, and are resolved
in the container's file system namespace.</para>
<para>This is for containers which have several bootable directories in them; for example, several
<ulink url="https://ostree.readthedocs.io/en/latest/">OSTree</ulink> deployments. It emulates the behavior of
the boot loader and initial RAM disk which normally select which directory to mount as the root and start the
container's PID 1 in.</para></listitem>
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>Execution Options</title>
<variablelist>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
<varlistentry>
<term><option>-a</option></term>
<term><option>--as-pid2</option></term>
<listitem><para>Invoke the shell or specified program as process ID (PID) 2 instead of PID 1 (init). By
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
default, if neither this option nor <option>--boot</option> is used, the selected program is run as the process
with PID 1, a mode only suitable for programs that are aware of the special semantics that the process with
PID 1 has on UNIX. For example, it needs to reap all processes reparented to it, and should implement
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
<command>sysvinit</command> compatible signal handling (specifically: it needs to reboot on SIGINT, reexecute
on SIGTERM, reload configuration on SIGHUP, and so on). With <option>--as-pid2</option> a minimal stub init
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
process is run as PID 1 and the selected program is executed as PID 2 (and hence does not need to implement any
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
special semantics). The stub init process will reap processes as necessary and react appropriately to
signals. It is recommended to use this mode to invoke arbitrary commands in containers, unless they have been
modified to run correctly as PID 1. Or in other words: this switch should be used for pretty much all commands,
except when the command refers to an init or shell implementation, as these are generally capable of running
nspawn: deprecate --share-system support This removes the --share-system switch: from the documentation, the --help text as well as the command line parsing. It's an ugly option, given that it kinda contradicts the whole concept of PID namespaces that nspawn implements. Since it's barely ever used, let's just deprecate it and remove it from the options. It might be useful as a debugging option, hence the functionality is kept around for now, exposed via an undocumented $SYSTEMD_NSPAWN_SHARE_SYSTEM environment variable.
2016-07-27 15:56:17 +03:00
correctly as PID 1. This option may not be combined with <option>--boot</option>.</para>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
</listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>-b</option></term>
<term><option>--boot</option></term>
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
<listitem><para>Automatically search for an init program and invoke it as PID 1, instead of a shell or a user
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
supplied program. If this option is used, arguments specified on the command line are used as arguments for the
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
init program. This option may not be combined with <option>--as-pid2</option>.</para>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
<para>The following table explains the different modes of invocation and relationship to
<option>--as-pid2</option> (see above):</para>
<table>
<title>Invocation Mode</title>
<tgroup cols='2' align='left' colsep='1' rowsep='1'>
<colspec colname="switch" />
<colspec colname="explanation" />
<thead>
<row>
<entry>Switch</entry>
<entry>Explanation</entry>
</row>
</thead>
<tbody>
<row>
<entry>Neither <option>--as-pid2</option> nor <option>--boot</option> specified</entry>
man: minor nspawn doc fixes
2016-02-24 16:08:53 +03:00
<entry>The passed parameters are interpreted as the command line, which is executed as PID 1 in the container.</entry>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
</row>
<row>
<entry><option>--as-pid2</option> specified</entry>
man: minor nspawn doc fixes
2016-02-24 16:08:53 +03:00
<entry>The passed parameters are interpreted as the command line, which is executed as PID 2 in the container. A stub init process is run as PID 1.</entry>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
</row>
<row>
<entry><option>--boot</option> specified</entry>
man: generalize "binary" to "program" (#7668) Systemd services are permitted to be scripts, as well as binary executables. The same also applies to the underlying /sbin/mount and /sbin/swapon. It is not necessary for the user to consider what type of program file these are. Nor is it necessary with systemd-nspawn, to distinguish between init as a "binary" v.s. a user-specified "program". Also fix a couple of grammar nits in the modified sentences.
2017-12-16 13:48:12 +03:00
<entry>An init program is automatically searched for and run as PID 1 in the container. The passed parameters are used as invocation parameters for this process.</entry>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
</row>
</tbody>
</tgroup>
</table>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<para>Note that <option>--boot</option> is the default mode of operation if the
<filename>systemd-nspawn@.service</filename> template unit file is used.</para>
nspawn: optionally run a stub init process as PID 1 This adds a new switch --as-pid2, which allows running commands as PID 2, while a stub init process is run as PID 1. This is useful in order to run arbitrary commands in a container, as PID1's semantics are different from all other processes regarding reaping of unknown children or signal handling.
2016-02-03 22:32:06 +03:00
</listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
nspawn: add new --chdir= switch Fixes: #2192
2016-02-02 03:52:01 +03:00
<varlistentry>
<term><option>--chdir=</option></term>
<listitem><para>Change to the specified working directory before invoking the process in the container. Expects
an absolute path in the container's file system namespace.</para></listitem>
</varlistentry>
nspawn: Add support for sysroot pivoting (#5258) Add a new --pivot-root argument to systemd-nspawn, which specifies a directory to pivot to / inside the container; while the original / is pivoted to another specified directory (if provided). This adds support for booting container images which may contain several bootable sysroots, as is common with OSTree disk images. When these disk images are booted on real hardware, ostree-prepare-root is run in conjunction with sysroot.mount in the initramfs to achieve the same results.
2017-02-08 18:54:31 +03:00
<varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<term><option>-E <replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term>
<term><option>--setenv=<replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term>
nspawn: Add support for sysroot pivoting (#5258) Add a new --pivot-root argument to systemd-nspawn, which specifies a directory to pivot to / inside the container; while the original / is pivoted to another specified directory (if provided). This adds support for booting container images which may contain several bootable sysroots, as is common with OSTree disk images. When these disk images are booted on real hardware, ostree-prepare-root is run in conjunction with sysroot.mount in the initramfs to achieve the same results.
2017-02-08 18:54:31 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<listitem><para>Specifies an environment variable assignment
to pass to the init process in the container, in the format
<literal>NAME=VALUE</literal>. This may be used to override
the default variables or to set additional variables. This
parameter may be used more than once.</para></listitem>
nspawn: Add support for sysroot pivoting (#5258) Add a new --pivot-root argument to systemd-nspawn, which specifies a directory to pivot to / inside the container; while the original / is pivoted to another specified directory (if provided). This adds support for booting container images which may contain several bootable sysroots, as is common with OSTree disk images. When these disk images are booted on real hardware, ostree-prepare-root is run in conjunction with sysroot.mount in the initramfs to achieve the same results.
2017-02-08 18:54:31 +03:00
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>-u</option></term>
<term><option>--user=</option></term>
tree-wide: fixes for assorted grammar and spelling issues Fixes #16363. Also includes some changes where I generalized the pattern.
2020-07-06 11:49:59 +03:00
<listitem><para>After transitioning into the container, change to the specified user defined in the
container's user database. Like all other systemd-nspawn features, this is not a security feature and
provides protection against accidental destructive operations only.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>--kill-signal=</option></term>
<listitem><para>Specify the process signal to send to the container's PID 1 when nspawn itself receives
<constant>SIGTERM</constant>, in order to trigger an orderly shutdown of the container. Defaults to
<constant>SIGRTMIN+3</constant> if <option>--boot</option> is used (on systemd-compatible init systems
<constant>SIGRTMIN+3</constant> triggers an orderly shutdown). If <option>--boot</option> is not used and this
option is not specified the container's processes are terminated abruptly via <constant>SIGKILL</constant>. For
a list of valid signals, see <citerefentry
project='man-pages'><refentrytitle>signal</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--notify-ready=</option></term>
<listitem><para>Configures support for notifications from the container's init process.
<option>--notify-ready=</option> takes a boolean (<option>no</option> and <option>yes</option>).
With option <option>no</option> systemd-nspawn notifies systemd
with a <literal>READY=1</literal> message when the init process is created.
With option <option>yes</option> systemd-nspawn waits for the
<literal>READY=1</literal> message from the init process in the container
before sending its own to systemd. For more details about notifications
man: match parentheses Files found with: for f in *; do \ l=`tr -d '[^(]' < $f | wc -c`; \ r=`tr -d '[^)]' < $f | wc -c`; \ if [ $l -ne $r ]; then \ echo $f $l $r; \ fi; \ done
2020-07-06 20:46:01 +03:00
see <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>System Identity Options</title>
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>-M</option></term>
<term><option>--machine=</option></term>
<listitem><para>Sets the machine name for this container. This
name may be used to identify this container during its runtime
(for example in tools like
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
and similar), and is used to initialize the container's
hostname (which the container can choose to override,
however). If not specified, the last component of the root
directory path of the container is used, possibly suffixed
with a random identifier in case <option>--ephemeral</option>
mode is selected. If the root directory selected is the host's
root directory the host's hostname is used as default
instead.</para></listitem>
</varlistentry>
nspawn: make the hostname of the container explicitly configurable with a new --hostname= switch Previously, the container's hostname was exclusively initialized from the machine name configured with --machine=, i.e. the internal name and the external name used for and by the container was synchronized. This adds a new option --hostname= that optionally allows the internal name to deviate from the external name. This new option is mainly useful to ultimately implement the OCI runtime spec directly in nspawn, but it might be useful on its own for some other usecases too.
2018-05-07 19:37:32 +03:00
<varlistentry>
<term><option>--hostname=</option></term>
<listitem><para>Controls the hostname to set within the container, if different from the machine name. Expects
a valid hostname as argument. If this option is used, the kernel hostname of the container will be set to this
value, otherwise it will be initialized to the machine name as controlled by the <option>--machine=</option>
option described above. The machine name is used for various aspect of identification of the container from the
outside, the kernel hostname configurable with this option is useful for the container to identify itself from
the inside. It is usually a good idea to keep both forms of identification synchronized, in order to avoid
confusion. It is hence recommended to avoid usage of this option, and use <option>--machine=</option>
exclusively. Note that regardless whether the container's hostname is initialized from the name set with
<option>--hostname=</option> or the one set with <option>--machine=</option>, the container can later override
its kernel hostname freely on its own as well.</para>
</listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--uuid=</option></term>
<listitem><para>Set the specified UUID for the container. The
init system will initialize
<filename>/etc/machine-id</filename> from this if this file is
nspawn: always setup machine id We check /etc/machine-id of the container and if it is already populated we use value from there, possibly ignoring value of --uuid option from the command line. When dealing with R/O image we setup transient machine id. Once we determined machine id of the container, we use this value for registration with systemd-machined and we also export it via container_uuid environment variable. As registration with systemd-machined is done by the main nspawn process we communicate container machine id established by setup_machine_id from outer child to the main process by unix domain socket. Similarly to PID of inner child.
2016-04-08 14:22:54 +03:00
not set yet. Note that this option takes effect only if
<filename>/etc/machine-id</filename> in the container is
unpopulated.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</refsect2><refsect2>
<title>Property Options</title>
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
man: nspawn: add missing option
2018-01-10 17:20:20 +03:00
<term><option>-S</option></term>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<term><option>--slice=</option></term>
nspawn: register a scope for the unit if --register=no is specified (#6166) Previously, only when --register=yes was set (the default) the invoked container would get its own scope, created by machined on behalf of nspawn. With this change if --register=no is set nspawn will still get its own scope (which is a good thing, so that --slice= and --property= take effect), but this is not done through machined but by registering a scope unit directly in PID 1. Summary: --register=yes → allocate a new scope through machined (the default) --register=yes --keep-unit → use the unit we are already running in an register with machined --register=no → allocate a new scope directly, but no machined --register=no --keep-unit → do not allocate nor register anything Fixes: #5823
2017-06-28 20:22:46 +03:00
<listitem><para>Make the container part of the specified slice, instead of the default
<filename>machine.slice</filename>. This applies only if the machine is run in its own scope unit, i.e. if
<option>--keep-unit</option> isn't used.</para>
nspawn: add support for --property= to set scope properties This is similar to systemd-run's --property= setting.
2015-02-18 21:38:55 +03:00
</listitem>
</varlistentry>
<varlistentry>
<term><option>--property=</option></term>
nspawn: register a scope for the unit if --register=no is specified (#6166) Previously, only when --register=yes was set (the default) the invoked container would get its own scope, created by machined on behalf of nspawn. With this change if --register=no is set nspawn will still get its own scope (which is a good thing, so that --slice= and --property= take effect), but this is not done through machined but by registering a scope unit directly in PID 1. Summary: --register=yes → allocate a new scope through machined (the default) --register=yes --keep-unit → use the unit we are already running in an register with machined --register=no → allocate a new scope directly, but no machined --register=no --keep-unit → do not allocate nor register anything Fixes: #5823
2017-06-28 20:22:46 +03:00
<listitem><para>Set a unit property on the scope unit to register for the machine. This applies only if the
machine is run in its own scope unit, i.e. if <option>--keep-unit</option> isn't used. Takes unit property
assignments in the same format as <command>systemctl set-property</command>. This is useful to set memory
limits and similar for container.</para>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</listitem>
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>--register=</option></term>
<listitem><para>Controls whether the container is registered with
<citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. Takes a
boolean argument, which defaults to <literal>yes</literal>. This option should be enabled when the container
runs a full Operating System (more specifically: a system and service manager as PID 1), and is useful to
ensure that the container is accessible via
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> and shown by
tools such as <citerefentry
project='man-pages'><refentrytitle>ps</refentrytitle><manvolnum>1</manvolnum></citerefentry>. If the container
does not run a service manager, it is recommended to set this option to
<literal>no</literal>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--keep-unit</option></term>
<listitem><para>Instead of creating a transient scope unit to run the container in, simply use the service or
scope unit <command>systemd-nspawn</command> has been invoked in. If <option>--register=yes</option> is set
this unit is registered with
<citerefentry><refentrytitle>systemd-machined</refentrytitle><manvolnum>8</manvolnum></citerefentry>. This
switch should be used if <command>systemd-nspawn</command> is invoked from within a service unit, and the
service unit's sole purpose is to run a single <command>systemd-nspawn</command> container. This option is not
available if run from a user session.</para>
<para>Note that passing <option>--keep-unit</option> disables the effect of <option>--slice=</option> and
<option>--property=</option>. Use <option>--keep-unit</option> and <option>--register=no</option> in
combination to disable any kind of unit allocation or registration with
<command>systemd-machined</command>.</para></listitem>
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>User Namespacing Options</title>
<variablelist>
nspawn: finish user namespace support
2015-05-21 17:30:58 +03:00
<varlistentry>
<term><option>--private-users=</option></term>
man: document the new user namespacing options
2016-04-22 14:46:23 +03:00
<listitem><para>Controls user namespacing. If enabled, the container will run with its own private set of UNIX
user and group ids (UIDs and GIDs). This involves mapping the private UIDs/GIDs used in the container (starting
with the container's root user 0 and up) to a range of UIDs/GIDs on the host that are not used for other
purposes (usually in the range beyond the host's UID/GID 65536). The parameter may be specified as follows:</para>
<orderedlist>
man: typo fixes A mix of fixes for typos and UK english
2016-10-13 00:02:44 +03:00
<listitem><para>If one or two colon-separated numbers are specified, user namespacing is turned on. The first
nspawn,man: fix parsing of numeric args for --private-users, accept any boolean This is like the previous reverted commit, but any boolean is still accepted, not just "yes" and "no". Man page is adjusted to match the code.
2016-10-10 18:12:57 +03:00
parameter specifies the first host UID/GID to assign to the container, the second parameter specifies the
number of host UIDs/GIDs to assign to the container. If the second parameter is omitted, 65536 UIDs/GIDs are
assigned.</para></listitem>
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<listitem><para>If the parameter is <literal>yes</literal>, user namespacing is turned on. The
UID/GID range to use is determined automatically from the file ownership of the root directory of
the container's directory tree. To use this option, make sure to prepare the directory tree in
advance, and ensure that all files and directories in it are owned by UIDs/GIDs in the range you'd
like to use. Also, make sure that used file ACLs exclusively reference UIDs/GIDs in the appropriate
range. In this mode, the number of UIDs/GIDs assigned to the container is 65536, and the owner
UID/GID of the root directory must be a multiple of 65536.</para></listitem>
<listitem><para>If the parameter is <literal>no</literal>, user namespacing is turned off. This is
the default.</para>
nspawn,man: fix parsing of numeric args for --private-users, accept any boolean This is like the previous reverted commit, but any boolean is still accepted, not just "yes" and "no". Man page is adjusted to match the code.
2016-10-10 18:12:57 +03:00
</listitem>
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<listitem><para>If the parameter is <literal>identity</literal>, user namespacing is employed with
an identity mapping for the first 65536 UIDs/GIDs. This is mostly equivalent to
<option>--private-users=0:65536</option>. While it does not provide UID/GID isolation, since all
host and container UIDs/GIDs are chosen identically it does provide process capability isolation,
and hence is often a good choice if proper user namespacing with distinct UID maps is not
appropriate.</para></listitem>
<listitem><para>The special value <literal>pick</literal> turns on user namespacing. In this case
the UID/GID range is automatically chosen. As first step, the file owner UID/GID of the root
directory of the container's directory tree is read, and it is checked that no other container is
currently using it. If this check is successful, the UID/GID range determined this way is used,
similar to the behavior if <literal>yes</literal> is specified. If the check is not successful (and
thus the UID/GID range indicated in the root directory's file owner is already used elsewhere) a
new – currently unused – UID/GID range of 65536 UIDs/GIDs is randomly chosen between the host
UID/GIDs of 524288 and 1878982656, always starting at a multiple of 65536, and, if possible,
consistently hashed from the machine name. This setting implies
<option>--private-users-ownership=auto</option> (see below), which possibly has the effect that the
files and directories in the container's directory tree will be owned by the appropriate users of
the range picked. Using this option makes user namespace behavior fully automatic. Note that the
first invocation of a previously unused container image might result in picking a new UID/GID range
for it, and thus in the (possibly expensive) file ownership adjustment operation. However,
subsequent invocations of the container will be cheap (unless of course the picked UID/GID range is
assigned to a different use by then).</para></listitem>
man: document the new user namespacing options
2016-04-22 14:46:23 +03:00
</orderedlist>
<para>It is recommended to assign at least 65536 UIDs/GIDs to each container, so that the usable UID/GID range in the
container covers 16 bit. For best security, do not assign overlapping UID/GID ranges to multiple containers. It is
hence a good idea to use the upper 16 bit of the host 32-bit UIDs/GIDs as container identifier, while the lower 16
man: typo fixes A mix of fixes for typos and UK english
2016-10-13 00:02:44 +03:00
bit encode the container UID/GID used. This is in fact the behavior enforced by the
man: document the new user namespacing options
2016-04-22 14:46:23 +03:00
<option>--private-users=pick</option> option.</para>
<para>When user namespaces are used, the GID range assigned to each container is always chosen identical to the
UID range.</para>
<para>In most cases, using <option>--private-users=pick</option> is the recommended option as it enhances
container security massively and operates fully automatically in most cases.</para>
<para>Note that the picked UID/GID range is not written to <filename>/etc/passwd</filename> or
<filename>/etc/group</filename>. In fact, the allocation of the range is not stored persistently anywhere,
man: document that user namespacing complicates file copies
2017-02-16 16:38:05 +03:00
except in the file ownership of the files and directories of the container.</para>
<para>Note that when user namespacing is used file ownership on disk reflects this, and all of the container's
files and directories are owned by the container's effective user and group IDs. This means that copying files
from and to the container image requires correction of the numeric UID/GID values, according to the UID/GID
shift applied.</para></listitem>
nspawn: finish user namespace support
2015-05-21 17:30:58 +03:00
</varlistentry>
man: document the new user namespacing options
2016-04-22 14:46:23 +03:00
<varlistentry>
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<term><option>--private-users-ownership=</option></term>
<listitem><para>Controls how to adjust the container image's UIDs and GIDs to match the UID/GID range
chosen with <option>--private-users=</option>, see above. Takes one of <literal>off</literal> (to
leave the image as is), <literal>chown</literal> (to recursively <function>chown()</function> the
container's directory tree as needed), <literal>map</literal> (in order to use transparent ID mapping
mounts) or <literal>auto</literal> for automatically using <literal>map</literal> where available and
<literal>chown</literal> where not.</para>
<para>If <literal>chown</literal> is selected, all files and directories in the container's directory
tree will be adjusted so that they are owned by the appropriate UIDs/GIDs selected for the container
(see above). This operation is potentially expensive, as it involves iterating through the full
directory tree of the container. Besides actual file ownership, file ACLs are adjusted as
well.</para>
<para>Typically <literal>map</literal> is the best choice, since it transparently maps UIDs/GIDs in
memory as needed without modifying the image, and without requiring an expensive recursive adjustment
operation. However, it is not available for all file systems, currently.</para>
<para>The <option>--private-users-ownership=auto</option> option is implied if
<option>--private-users=pick</option> is used. This option has no effect if user namespacing is not
used.</para></listitem>
man: document the new user namespacing options
2016-04-22 14:46:23 +03:00
</varlistentry>
nspawn: finish user namespace support
2015-05-21 17:30:58 +03:00
man: describe how to reverse systemd-nspawn -U Now that systemd-nspawn@.service includes -U, more users might be interested in this tidbit ;)
2016-10-09 18:48:01 +03:00
<varlistentry>
<term><option>-U</option></term>
<listitem><para>If the kernel supports the user namespaces feature, equivalent to
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<option>--private-users=pick --private-users-ownership=auto</option>, otherwise equivalent to
man: describe how to reverse systemd-nspawn -U Now that systemd-nspawn@.service includes -U, more users might be interested in this tidbit ;)
2016-10-09 18:48:01 +03:00
<option>--private-users=no</option>.</para>
<para>Note that <option>-U</option> is the default if the
<filename>systemd-nspawn@.service</filename> template unit file is used.</para>
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<para>Note: it is possible to undo the effect of <option>--private-users-ownership=chown</option> (or
man: describe how to reverse systemd-nspawn -U Now that systemd-nspawn@.service includes -U, more users might be interested in this tidbit ;)
2016-10-09 18:48:01 +03:00
<option>-U</option>) on the file system by redoing the operation with the first UID of 0:</para>
man: document new nspawn ID mapping mounts features
2021-04-27 19:31:24 +03:00
<programlisting>systemd-nspawn … --private-users=0 --private-users-ownership=chown</programlisting>
man: describe how to reverse systemd-nspawn -U Now that systemd-nspawn@.service includes -U, more users might be interested in this tidbit ;)
2016-10-09 18:48:01 +03:00
</listitem>
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</variablelist>
</refsect2><refsect2>
<title>Networking Options</title>
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--private-network</option></term>
<listitem><para>Disconnect networking of the container from
the host. This makes all network interfaces unavailable in the
container, with the exception of the loopback device and those
specified with <option>--network-interface=</option> and
configured with <option>--network-veth</option>. If this
man: use <constant> for capability names in nspawn page
2019-11-20 20:35:26 +03:00
option is specified, the <constant>CAP_NET_ADMIN</constant> capability will be
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
added to the set of capabilities the container retains. The
man: add a note that nspawn gives access to network by default Fixes #6546.
2018-03-21 18:07:20 +03:00
latter may be disabled by using <option>--drop-capability=</option>.
If this option is not specified (or implied by one of the options
listed below), the container will have full access to the host network.
</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>--network-interface=</option></term>
man: document how to use --network-interface= during boot Fixes: #18793
2021-03-03 19:28:09 +03:00
<listitem><para>Assign the specified network interface to the container. This will remove the
specified interface from the calling namespace and place it in the container. When the container
terminates, it is moved back to the calling namespace. Note that
<option>--network-interface=</option> implies <option>--private-network</option>. This option may be
used more than once to add multiple network interfaces to the container.</para>
<para>Note that any network interface specified this way must already exist at the time the container
is started. If the container shall be started automatically at boot via a
<filename>systemd-nspawn@.service</filename> unit file instance, it might hence make sense to add a
unit file drop-in to the service instance
(e.g. <filename>/etc/systemd/system/systemd-nspawn@foobar.service.d/50-network.conf</filename>) with
contents like the following:</para>
<programlisting>[Unit]
Wants=sys-subsystem-net-devices-ens1.device
After=sys-subsystem-net-devices-ens1.device</programlisting>
<para>This will make sure that activation of the container service will be delayed until the
<literal>ens1</literal> network interface has shown up. This is required since hardware probing is
fully asynchronous, and network interfaces might be discovered only later during the boot process,
after the container would normally be started without these explicit dependencies.</para>
</listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>--network-macvlan=</option></term>
man: document how to use --network-interface= during boot Fixes: #18793
2021-03-03 19:28:09 +03:00
<listitem><para>Create a <literal>macvlan</literal> interface of the specified Ethernet network
interface and add it to the container. A <literal>macvlan</literal> interface is a virtual interface
that adds a second MAC address to an existing physical Ethernet link. The interface in the container
will be named after the interface on the host, prefixed with <literal>mv-</literal>. Note that
<option>--network-macvlan=</option> implies <option>--private-network</option>. This option may be
used more than once to add multiple network interfaces to the container.</para>
<para>As with <option>--network-interface=</option>, the underlying Ethernet network interface must
already exist at the time the container is started, and thus similar unit file drop-ins as described
above might be useful.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>--network-ipvlan=</option></term>
man: document how to use --network-interface= during boot Fixes: #18793
2021-03-03 19:28:09 +03:00
<listitem><para>Create an <literal>ipvlan</literal> interface of the specified Ethernet network
interface and add it to the container. An <literal>ipvlan</literal> interface is a virtual interface,
similar to a <literal>macvlan</literal> interface, which uses the same MAC address as the underlying
interface. The interface in the container will be named after the interface on the host, prefixed
with <literal>iv-</literal>. Note that <option>--network-ipvlan=</option> implies
<option>--private-network</option>. This option may be used more than once to add multiple network
interfaces to the container.</para>
<para>As with <option>--network-interface=</option>, the underlying Ethernet network interface must
already exist at the time the container is started, and thus similar unit file drop-ins as described
above might be useful.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>-n</option></term>
<term><option>--network-veth</option></term>
man: document that nspawn's host0 and ve-* interfaces have default config in networkd
2016-05-06 21:50:16 +03:00
<listitem><para>Create a virtual Ethernet link (<literal>veth</literal>) between host and container. The host
side of the Ethernet link will be available as a network interface named after the container's name (as
specified with <option>--machine=</option>), prefixed with <literal>ve-</literal>. The container side of the
Ethernet link will be named <literal>host0</literal>. The <option>--network-veth</option> option implies
<option>--private-network</option>.</para>
<para>Note that
<citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
includes by default a network file <filename>/usr/lib/systemd/network/80-container-ve.network</filename>
matching the host-side interfaces created this way, which contains settings to enable automatic address
provisioning on the created virtual link via DHCP, as well as automatic IP routing onto the host's external
network interfaces. It also contains <filename>/usr/lib/systemd/network/80-container-host0.network</filename>
matching the container-side interface created this way, containing settings to enable client side address
assignment via DHCP. In case <filename>systemd-networkd</filename> is running on both the host and inside the
container, automatic IP communication from the container to the host is thus available, with further
connectivity to the external network.</para>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
<para>Note that <option>--network-veth</option> is the default if the
<filename>systemd-nspawn@.service</filename> template unit file is used.</para>
man: document the network interface size limits --network-veth= enforces Fixes: #10721
2019-03-13 18:24:59 +03:00
<para>Note that on Linux network interface names may have a length of 15 characters at maximum, while
container names may have a length up to 64 characters. As this option derives the host-side interface
name from the container name the name is possibly truncated. Thus, care needs to be taken to ensure
that interface names remain unique in this case, or even better container names are generally not
nspawn: Generate unique short veth names This commit lowers the chance of having veth name conflicts for machines created with similar names. Replaces: #12865 Fixes: #13417
2019-06-24 01:24:18 +03:00
chosen longer than 12 characters, to avoid the truncation. If the name is truncated,
<command>systemd-nspawn</command> will automatically append a 4-digit hash value to the name to
reduce the chance of collisions. However, the hash algorithm is not collision-free. (See
<citerefentry><refentrytitle>systemd.net-naming-scheme</refentrytitle><manvolnum>7</manvolnum></citerefentry>
for details on older naming algorithms for this interface). Alternatively, the
man: document the network interface size limits --network-veth= enforces Fixes: #10721
2019-03-13 18:24:59 +03:00
<option>--network-veth-extra=</option> option may be used, which allows free configuration of the
host-side interface name independently of the container name — but might require a bit more
additional configuration in case bridging in a fashion similar to <option>--network-bridge=</option>
is desired.</para>
man: document that nspawn's host0 and ve-* interfaces have default config in networkd
2016-05-06 21:50:16 +03:00
</listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
nspawn: add new --network-veth-extra= switch for defining additional veth links The new switch operates like --network-veth, but may be specified multiple times (to define multiple link pairs) and allows flexible definition of the interface names. This is an independent reimplementation of #1678, but defines different semantics, keeping the behaviour completely independent of --network-veth. It also comes will full hook-up for .nspawn files, and the matching documentation.
2015-11-12 23:54:28 +03:00
<varlistentry>
<term><option>--network-veth-extra=</option></term>
<listitem><para>Adds an additional virtual Ethernet link
between host and container. Takes a colon-separated pair of
host interface name and container interface name. The latter
may be omitted in which case the container and host sides will
be assigned the same name. This switch is independent of
tree-wide: use mdash instead of a two minuses
2016-04-22 05:57:06 +03:00
<option>--network-veth</option>, and — in contrast — may be
nspawn: add new --network-veth-extra= switch for defining additional veth links The new switch operates like --network-veth, but may be specified multiple times (to define multiple link pairs) and allows flexible definition of the interface names. This is an independent reimplementation of #1678, but defines different semantics, keeping the behaviour completely independent of --network-veth. It also comes will full hook-up for .nspawn files, and the matching documentation.
2015-11-12 23:54:28 +03:00
used multiple times, and allows configuration of the network
interface names. Note that <option>--network-bridge=</option>
has no effect on interfaces created with
<option>--network-veth-extra=</option>.</para></listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--network-bridge=</option></term>
man: document the network interface size limits --network-veth= enforces Fixes: #10721
2019-03-13 18:24:59 +03:00
<listitem><para>Adds the host side of the Ethernet link created with <option>--network-veth</option>
to the specified Ethernet bridge interface. Expects a valid network interface name of a bridge device
as argument. Note that <option>--network-bridge=</option> implies <option>--network-veth</option>. If
this option is used, the host side of the Ethernet link will use the <literal>vb-</literal> prefix
instead of <literal>ve-</literal>. Regardless of the used naming prefix the same network interface
name length limits imposed by Linux apply, along with the complications this creates (for details see
man: document how to use --network-interface= during boot Fixes: #18793
2021-03-03 19:28:09 +03:00
above).</para>
<para>As with <option>--network-interface=</option>, the underlying bridge network interface must
already exist at the time the container is started, and thus similar unit file drop-ins as described
above might be useful.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: add documentation for the new --network-zone= concept of nspawn
2016-05-06 22:04:52 +03:00
<varlistentry>
<term><option>--network-zone=</option></term>
<listitem><para>Creates a virtual Ethernet link (<literal>veth</literal>) to the container and adds it to an
automatically managed Ethernet bridge interface. The bridge interface is named after the passed argument,
prefixed with <literal>vz-</literal>. The bridge interface is automatically created when the first container
configured for its name is started, and is automatically removed when the last container configured for its
name exits. Hence, each bridge interface configured this way exists only as long as there's at least one
container referencing it running. This option is very similar to <option>--network-bridge=</option>, besides
this automatic creation/removal of the bridge device.</para>
<para>This setting makes it easy to place multiple related containers on a common, virtual Ethernet-based
broadcast domain, here called a "zone". Each container may only be part of one zone, but each zone may contain
any number of containers. Each zone is referenced by its name. Names may be chosen freely (as long as they form
valid network interface names when prefixed with <literal>vz-</literal>), and it is sufficient to pass the same
man: fix typo (`--network-zones` → `--network-zone`)
2017-05-13 21:55:03 +03:00
name to the <option>--network-zone=</option> switch of the various concurrently running containers to join
man: add documentation for the new --network-zone= concept of nspawn
2016-05-06 22:04:52 +03:00
them in one zone.</para>
<para>Note that
<citerefentry><refentrytitle>systemd-networkd.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
includes by default a network file <filename>/usr/lib/systemd/network/80-container-vz.network</filename>
matching the bridge interfaces created this way, which contains settings to enable automatic address
provisioning on the created virtual network via DHCP, as well as automatic IP routing onto the host's external
network interfaces. Using <option>--network-zone=</option> is hence in most cases fully automatic and
sufficient to connect multiple local containers in a joined broadcast domain to the host, with further
connectivity to the external network.</para>
</listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<term><option>--network-namespace-path=</option></term>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<listitem><para>Takes the path to a file representing a kernel
network namespace that the container shall run in. The specified path
should refer to a (possibly bind-mounted) network namespace file, as
exposed by the kernel below <filename>/proc/$PID/ns/net</filename>.
This makes the container enter the given network namespace. One of the
typical use cases is to give a network namespace under
<filename>/run/netns</filename> created by <citerefentry
project='man-pages'><refentrytitle>ip-netns</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
for example, <option>--network-namespace-path=/run/netns/foo</option>.
Note that this option cannot be used together with other
network-related options, such as <option>--private-network</option>
or <option>--network-interface=</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>-p</option></term>
<term><option>--port=</option></term>
<listitem><para>If private networking is enabled, maps an IP
port on the host onto an IP port on the container. Takes a
protocol specifier (either <literal>tcp</literal> or
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<literal>udp</literal>), separated by a colon from a host port
number in the range 1 to 65535, separated by a colon from a
container port number in the range from 1 to 65535. The
protocol specifier and its separating colon may be omitted, in
which case <literal>tcp</literal> is assumed. The container
fix typos in systemd-nspawn man page
2015-05-23 06:11:01 +03:00
port number and its colon may be omitted, in which case the
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
same port as the host port is implied. This option is only
doc: correct orthography, word forms and missing/extraneous words
2014-08-03 09:11:37 +04:00
supported if private networking is used, such as with
man: add documentation for the new --network-zone= concept of nspawn
2016-05-06 22:04:52 +03:00
<option>--network-veth</option>, <option>--network-zone=</option>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<option>--network-bridge=</option>.</para></listitem>
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</refsect2><refsect2>
<title>Security Options</title>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--capability=</option></term>
man: use <constant> for capability names in nspawn page
2019-11-20 20:35:26 +03:00
<listitem><para>List one or more additional capabilities to grant the container. Takes a
comma-separated list of capability names, see <citerefentry
project='man-pages'><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>
man: systemd-nspawn: fix list of default capabilities (#7925) * Sort them alphabetically. * Add CAP_MKNOD (commit 7f112f50fe added it). the list is now in sync with the one at the top of nspawn.c
2018-01-18 22:11:11 +03:00
for more information. Note that the following capabilities will be granted in any way:
man: use <constant> for capability names in nspawn page
2019-11-20 20:35:26 +03:00
<constant>CAP_AUDIT_CONTROL</constant>, <constant>CAP_AUDIT_WRITE</constant>,
<constant>CAP_CHOWN</constant>, <constant>CAP_DAC_OVERRIDE</constant>,
<constant>CAP_DAC_READ_SEARCH</constant>, <constant>CAP_FOWNER</constant>,
<constant>CAP_FSETID</constant>, <constant>CAP_IPC_OWNER</constant>, <constant>CAP_KILL</constant>,
<constant>CAP_LEASE</constant>, <constant>CAP_LINUX_IMMUTABLE</constant>,
<constant>CAP_MKNOD</constant>, <constant>CAP_NET_BIND_SERVICE</constant>,
<constant>CAP_NET_BROADCAST</constant>, <constant>CAP_NET_RAW</constant>,
<constant>CAP_SETFCAP</constant>, <constant>CAP_SETGID</constant>, <constant>CAP_SETPCAP</constant>,
<constant>CAP_SETUID</constant>, <constant>CAP_SYS_ADMIN</constant>,
<constant>CAP_SYS_BOOT</constant>, <constant>CAP_SYS_CHROOT</constant>,
<constant>CAP_SYS_NICE</constant>, <constant>CAP_SYS_PTRACE</constant>,
<constant>CAP_SYS_RESOURCE</constant>, <constant>CAP_SYS_TTY_CONFIG</constant>. Also
<constant>CAP_NET_ADMIN</constant> is retained if <option>--private-network</option> is specified.
If the special value <literal>all</literal> is passed, all capabilities are retained.</para>
nspawn: dump capability list with --capabilities=help
2019-11-20 20:33:32 +03:00
<para>If the special value of <literal>help</literal> is passed, the program will print known
systemd-nspawn: Allow setting ambient capability set The old code was only able to pass the value 0 for the inheritable and ambient capability set when a non-root user was specified. However, sometimes it is useful to run a program in its own container with a user specification and some capabilities set. This is needed when the capabilities cannot be provided by file capabilities (because the file system is mounted with MS_NOSUID for additional security). This commit introduces the option --ambient-capability and the config file option AmbientCapability=. Both are used in a similar way to the existing Capability= setting. It changes the inheritable and ambient set (which is 0 by default). The code also checks that the settings for the bounding set (as defined by Capability= and DropCapability=) and the setting for the ambient set (as defined by AmbientCapability=) are compatible. Otherwise, the operation would fail in any way. Due to the current use of -1 to indicate no support for ambient capability set the special value "all" cannot be supported. Also, the setting of ambient capability is restricted to running a single program in the container payload.
2020-12-04 13:27:12 +03:00
capability names and exit.</para>
<para>This option sets the bounding set of capabilities which
also limits the ambient capabilities as given with the
<option>--ambient-capability=</option>.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
<varlistentry>
<term><option>--drop-capability=</option></term>
<listitem><para>Specify one or more additional capabilities to
drop for the container. This allows running the container with
fewer capabilities than the default (see
nspawn: dump capability list with --capabilities=help
2019-11-20 20:33:32 +03:00
above).</para>
<para>If the special value of <literal>help</literal> is passed, the program will print known
systemd-nspawn: Allow setting ambient capability set The old code was only able to pass the value 0 for the inheritable and ambient capability set when a non-root user was specified. However, sometimes it is useful to run a program in its own container with a user specification and some capabilities set. This is needed when the capabilities cannot be provided by file capabilities (because the file system is mounted with MS_NOSUID for additional security). This commit introduces the option --ambient-capability and the config file option AmbientCapability=. Both are used in a similar way to the existing Capability= setting. It changes the inheritable and ambient set (which is 0 by default). The code also checks that the settings for the bounding set (as defined by Capability= and DropCapability=) and the setting for the ambient set (as defined by AmbientCapability=) are compatible. Otherwise, the operation would fail in any way. Due to the current use of -1 to indicate no support for ambient capability set the special value "all" cannot be supported. Also, the setting of ambient capability is restricted to running a single program in the container payload.
2020-12-04 13:27:12 +03:00
capability names and exit.</para>
<para>This option sets the bounding set of capabilities which
also limits the ambient capabilities as given with the
<option>--ambient-capability=</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--ambient-capability=</option></term>
<listitem><para>Specify one or more additional capabilities to
pass in the inheritable and ambient set to the program started
within the container. The value <literal>all</literal> is not
supported for this setting.</para>
<para>All capabilities specified here must be in the set
allowed with the <option>--capability=</option> and
<option>--drop-capability=</option> options. Otherwise, an
error message will be shown.</para>
<para>This option cannot be combined with the boot mode of the
container (as requested via <option>--boot</option>).</para>
<para>If the special value of <literal>help</literal> is
passed, the program will print known capability names and
exit.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
nspawn: add a new --no-new-privileges= cmdline option to nspawn This simply controls the PR_SET_NO_NEW_PRIVS flag for the container. This too is primarily relevant to provide OCI runtime compaitiblity, but might have other uses too, in particular as it nicely complements the existing --capability= and --drop-capability= flags.
2018-05-07 20:35:48 +03:00
<varlistentry>
<term><option>--no-new-privileges=</option></term>
tree-wide: avoid some loaded terms https://tools.ietf.org/html/draft-knodel-terminology-02 https://lwn.net/Articles/823224/ This gets rid of most but not occasions of these loaded terms: 1. scsi_id and friends are something that is supposed to be removed from our tree (see #7594) 2. The test suite defines an API used by the ubuntu CI. We can remove this too later, but this needs to be done in sync with the ubuntu CI. 3. In some cases the terms are part of APIs we call or where we expose concepts the kernel names the way it names them. (In particular all remaining uses of the word "slave" in our codebase are like this, it's used by the POSIX PTY layer, by the network subsystem, the mount API and the block device subsystem). Getting rid of the term in these contexts would mean doing some major fixes of the kernel ABI first. Regarding the replacements: when whitelist/blacklist is used as noun we replace with with allow list/deny list, and when used as verb with allow-list/deny-list.
2020-06-23 09:31:16 +03:00
<listitem><para>Takes a boolean argument. Specifies the value of the
<constant>PR_SET_NO_NEW_PRIVS</constant> flag for the container payload. Defaults to off. When turned
on the payload code of the container cannot acquire new privileges, i.e. the "setuid" file bit as
well as file system capabilities will not have an effect anymore. See <citerefentry
project='man-pages'><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry> for
details about this flag. </para></listitem>
nspawn: add a new --no-new-privileges= cmdline option to nspawn This simply controls the PR_SET_NO_NEW_PRIVS flag for the container. This too is primarily relevant to provide OCI runtime compaitiblity, but might have other uses too, in particular as it nicely complements the existing --capability= and --drop-capability= flags.
2018-05-07 20:35:48 +03:00
</varlistentry>
nspawn: implement configurable syscall whitelisting/blacklisting Now that we have ported nspawn's seccomp code to the generic code in seccomp-util, let's extend it to support whitelisting and blacklisting of specific additional syscalls. This uses similar syntax as PID1's support for system call filtering, but in contrast to that always implements a blacklist (and not a whitelist), as we prepopulate the filter with a blacklist, and the unit's system call filter logic does not come with anything prepopulated. (Later on we might actually want to invert the logic here, and whitelist rather than blacklist things, but at this point let's not do that. In case we switch this over later, the syscall add/remove logic of this commit should be compatible conceptually.) Fixes: #5163 Replaces: #5944
2017-09-11 18:45:21 +03:00
<varlistentry>
tree-wide: avoid some loaded terms https://tools.ietf.org/html/draft-knodel-terminology-02 https://lwn.net/Articles/823224/ This gets rid of most but not occasions of these loaded terms: 1. scsi_id and friends are something that is supposed to be removed from our tree (see #7594) 2. The test suite defines an API used by the ubuntu CI. We can remove this too later, but this needs to be done in sync with the ubuntu CI. 3. In some cases the terms are part of APIs we call or where we expose concepts the kernel names the way it names them. (In particular all remaining uses of the word "slave" in our codebase are like this, it's used by the POSIX PTY layer, by the network subsystem, the mount API and the block device subsystem). Getting rid of the term in these contexts would mean doing some major fixes of the kernel ABI first. Regarding the replacements: when whitelist/blacklist is used as noun we replace with with allow list/deny list, and when used as verb with allow-list/deny-list.
2020-06-23 09:31:16 +03:00
<term><option>--system-call-filter=</option></term> <listitem><para>Alter the system call filter
applied to containers. Takes a space-separated list of system call names or group names (the latter
prefixed with <literal>@</literal>, as listed by the <command>syscall-filter</command> command of
man: don't claim systemd-analyze was documented as part of the man-pages project It's our own command, we document it in our own set of man pages.
2018-05-07 18:50:48 +03:00
<citerefentry><refentrytitle>systemd-analyze</refentrytitle><manvolnum>1</manvolnum></citerefentry>). Passed
tree-wide: avoid some loaded terms https://tools.ietf.org/html/draft-knodel-terminology-02 https://lwn.net/Articles/823224/ This gets rid of most but not occasions of these loaded terms: 1. scsi_id and friends are something that is supposed to be removed from our tree (see #7594) 2. The test suite defines an API used by the ubuntu CI. We can remove this too later, but this needs to be done in sync with the ubuntu CI. 3. In some cases the terms are part of APIs we call or where we expose concepts the kernel names the way it names them. (In particular all remaining uses of the word "slave" in our codebase are like this, it's used by the POSIX PTY layer, by the network subsystem, the mount API and the block device subsystem). Getting rid of the term in these contexts would mean doing some major fixes of the kernel ABI first. Regarding the replacements: when whitelist/blacklist is used as noun we replace with with allow list/deny list, and when used as verb with allow-list/deny-list.
2020-06-23 09:31:16 +03:00
system calls will be permitted. The list may optionally be prefixed by <literal>~</literal>, in which
case all listed system calls are prohibited. If this command line option is used multiple times the
configured lists are combined. If both a positive and a negative list (that is one system call list
without and one with the <literal>~</literal> prefix) are configured, the negative list takes
precedence over the positive list. Note that <command>systemd-nspawn</command> always implements a
system call allow list (as opposed to a deny list!), and this command line option hence adds or
removes entries from the default allow list, depending on the <literal>~</literal> prefix. Note that
the applied system call filter is also altered implicitly if additional capabilities are passed using
the <command>--capabilities=</command>.</para></listitem>
nspawn: implement configurable syscall whitelisting/blacklisting Now that we have ported nspawn's seccomp code to the generic code in seccomp-util, let's extend it to support whitelisting and blacklisting of specific additional syscalls. This uses similar syntax as PID1's support for system call filtering, but in contrast to that always implements a blacklist (and not a whitelist), as we prepopulate the filter with a blacklist, and the unit's system call filter logic does not come with anything prepopulated. (Later on we might actually want to invert the logic here, and whitelist rather than blacklist things, but at this point let's not do that. In case we switch this over later, the syscall add/remove logic of this commit should be compatible conceptually.) Fixes: #5163 Replaces: #5944
2017-09-11 18:45:21 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>-Z</option></term>
<term><option>--selinux-context=</option></term>
<listitem><para>Sets the SELinux security context to be used
to label processes in the container.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-L</option></term>
<term><option>--selinux-apifs-context=</option></term>
<listitem><para>Sets the SELinux security context to be used
to label files in the virtual API file systems in the
container.</para>
</listitem>
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>Resource Options</title>
<variablelist>
nspawn: add new --rlimit= switch, and always set resource limits explicitly for our container payloads This ensures we set the various resource limits of our container explicitly on each invocation so that we inherit less from our callers into the payload. By default resource limits are now set to the same values Linux generally passes to the host PID 1, thus minimizing needless differences between host and container environments. The limits are now also configurable using a new --rlimit= switch. This is preparation for teaching nspawn native OCI runtime support as OCI permits setting resource limits for container payloads, and it hence probably makes sense if we do too.
2018-05-07 18:59:18 +03:00
<varlistentry>
<term><option>--rlimit=</option></term>
<listitem><para>Sets the specified POSIX resource limit for the container payload. Expects an assignment of the
form
<literal><replaceable>LIMIT</replaceable>=<replaceable>SOFT</replaceable>:<replaceable>HARD</replaceable></literal>
or <literal><replaceable>LIMIT</replaceable>=<replaceable>VALUE</replaceable></literal>, where
<replaceable>LIMIT</replaceable> should refer to a resource limit type, such as
<constant>RLIMIT_NOFILE</constant> or <constant>RLIMIT_NICE</constant>. The <replaceable>SOFT</replaceable> and
<replaceable>HARD</replaceable> fields should refer to the numeric soft and hard resource limit values. If the
doc: more spelling fixes
2018-06-12 17:19:21 +03:00
second form is used, <replaceable>VALUE</replaceable> may specify a value that is used both as soft and hard
nspawn: add new --rlimit= switch, and always set resource limits explicitly for our container payloads This ensures we set the various resource limits of our container explicitly on each invocation so that we inherit less from our callers into the payload. By default resource limits are now set to the same values Linux generally passes to the host PID 1, thus minimizing needless differences between host and container environments. The limits are now also configurable using a new --rlimit= switch. This is preparation for teaching nspawn native OCI runtime support as OCI permits setting resource limits for container payloads, and it hence probably makes sense if we do too.
2018-05-07 18:59:18 +03:00
limit. In place of a numeric value the special string <literal>infinity</literal> may be used to turn off
resource limiting for the specific type of resource. This command line option may be used multiple times to
doc: more spelling fixes
2018-06-12 17:19:21 +03:00
control limits on multiple limit types. If used multiple times for the same limit type, the last use
nspawn: add new --rlimit= switch, and always set resource limits explicitly for our container payloads This ensures we set the various resource limits of our container explicitly on each invocation so that we inherit less from our callers into the payload. By default resource limits are now set to the same values Linux generally passes to the host PID 1, thus minimizing needless differences between host and container environments. The limits are now also configurable using a new --rlimit= switch. This is preparation for teaching nspawn native OCI runtime support as OCI permits setting resource limits for container payloads, and it hence probably makes sense if we do too.
2018-05-07 18:59:18 +03:00
wins. For details about resource limits see <citerefentry
project='man-pages'><refentrytitle>setrlimit</refentrytitle><manvolnum>2</manvolnum></citerefentry>. By default
resource limits for the container's init process (PID 1) are set to the same values the Linux kernel originally
passed to the host init system. Note that some resource limits are enforced on resources counted per user, in
particular <constant>RLIMIT_NPROC</constant>. This means that unless user namespacing is deployed
(i.e. <option>--private-users=</option> is used, see above), any limits set will be applied to the resource
usage of the same user on all local containers as well as the host. This means particular care needs to be
taken with these limits as they might be triggered by possibly less trusted code. Example:
<literal>--rlimit=RLIMIT_NOFILE=8192:16384</literal>.</para></listitem>
</varlistentry>
nspawn: add a new --oom-score-adjust= command line switch This is primarily useful in order to provide comprehensive OCI runtime compatibility with nspawn, but might have uses outside of it.
2018-05-07 22:17:09 +03:00
<varlistentry>
<term><option>--oom-score-adjust=</option></term>
<listitem><para>Changes the OOM ("Out Of Memory") score adjustment value for the container payload. This controls
<filename>/proc/self/oom_score_adj</filename> which influences the preference with which this container is
terminated when memory becomes scarce. For details see <citerefentry
project='man-pages'><refentrytitle>proc</refentrytitle><manvolnum>5</manvolnum></citerefentry>. Takes an
integer in the range -1000…1000.</para></listitem>
</varlistentry>
nspawn: add a new --cpu-affinity= switch Similar as the other options added before, this is primarily useful to provide comprehensive OCI runtime compatbility, but might be useful otherwise, too.
2018-05-07 22:47:15 +03:00
<varlistentry>
<term><option>--cpu-affinity=</option></term>
<listitem><para>Controls the CPU affinity of the container payload. Takes a comma separated list of CPU numbers
or number ranges (the latter's start and end value separated by dashes). See <citerefentry
project='man-pages'><refentrytitle>sched_setaffinity</refentrytitle><manvolnum>2</manvolnum></citerefentry> for
details.</para></listitem>
</varlistentry>
nspawn: make kill signal to use for PID 1 configurable
2015-02-26 00:04:48 +03:00
<varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<term><option>--personality=</option></term>
nspawn: improve man page (#3577) This change documents the existance of the systemd-nspawn@.service template unit file, which was previously not mentioned at all. Since the unit file uses slightly different default than nspawn invoked from the command line, these defaults are now explicitly documented too. A couple of further additions and changes are made, too. Replaces: #3497
2016-06-23 00:30:36 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<listitem><para>Control the architecture ("personality")
reported by
<citerefentry project='man-pages'><refentrytitle>uname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
in the container. Currently, only <literal>x86</literal> and
<literal>x86-64</literal> are supported. This is useful when
running a 32-bit container on a 64-bit host. If this setting
is not used, the personality reported in the container is the
same as the one reported on the host.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</refsect2><refsect2>
<title>Integration Options</title>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<variablelist>
nspawn: add greater control over how /etc/resolv.conf is handled Fixes: #8014 #1781
2018-05-12 22:50:57 +03:00
<varlistentry>
<term><option>--resolv-conf=</option></term>
man: document the new --resolv-conf= options
2020-04-21 19:56:30 +03:00
<listitem><para>Configures how <filename>/etc/resolv.conf</filename> inside of the container shall be
handled (i.e. DNS configuration synchronization from host to container). Takes one of
<literal>off</literal>, <literal>copy-host</literal>, <literal>copy-static</literal>,
<literal>copy-uplink</literal>, <literal>copy-stub</literal>, <literal>replace-host</literal>,
<literal>replace-static</literal>, <literal>replace-uplink</literal>,
<literal>replace-stub</literal>, <literal>bind-host</literal>, <literal>bind-static</literal>,
<literal>bind-uplink</literal>, <literal>bind-stub</literal>, <literal>delete</literal> or
<literal>auto</literal>.</para>
<para>If set to <literal>off</literal> the <filename>/etc/resolv.conf</filename> file in the
container is left as it is included in the image, and neither modified nor bind mounted over.</para>
<para>If set to <literal>copy-host</literal>, the <filename>/etc/resolv.conf</filename> file from the
host is copied into the container, unless the file exists already and is not a regular file (e.g. a
symlink). Similar, if <literal>replace-host</literal> is used the file is copied, replacing any
existing inode, including symlinks. Similar, if <literal>bind-host</literal> is used, the file is
bind mounted from the host into the container.</para>
<para>If set to <literal>copy-static</literal>, <literal>replace-static</literal> or
<literal>bind-static</literal> the static <filename>resolv.conf</filename> file supplied with
<citerefentry><refentrytitle>systemd-resolved.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
(specifically: <filename>/usr/lib/systemd/resolv.conf</filename>) is copied or bind mounted into the
container.</para>
<para>If set to <literal>copy-uplink</literal>, <literal>replace-uplink</literal> or
<literal>bind-uplink</literal> the uplink <filename>resolv.conf</filename> file managed by
<filename>systemd-resolved.service</filename> (specifically:
<filename>/run/systemd/resolve/resolv.conf</filename>) is copied or bind mounted into the
container.</para>
<para>If set to <literal>copy-stub</literal>, <literal>replace-stub</literal> or
<literal>bind-stub</literal> the stub <filename>resolv.conf</filename> file managed by
<filename>systemd-resolved.service</filename> (specifically:
<filename>/run/systemd/resolve/stub-resolv.conf</filename>) is copied or bind mounted into the
container.</para>
<para>If set to <literal>delete</literal> the <filename>/etc/resolv.conf</filename> file in the
container is deleted if it exists.</para>
<para>Finally, if set to <literal>auto</literal> the file is left as it is if private networking is
turned on (see <option>--private-network</option>). Otherwise, if
tree-wide: fixes for assorted grammar and spelling issues Fixes #16363. Also includes some changes where I generalized the pattern.
2020-07-06 11:49:59 +03:00
<filename>systemd-resolved.service</filename> is running its stub <filename>resolv.conf</filename>
file is used, and if not the host's <filename>/etc/resolv.conf</filename> file. In the latter cases
the file is copied if the image is writable, and bind mounted otherwise.</para>
man: document the new --resolv-conf= options
2020-04-21 19:56:30 +03:00
<para>It's recommended to use <literal>copy-…</literal> or <literal>replace-…</literal> if the
container shall be able to make changes to the DNS configuration on its own, deviating from the
host's settings. Otherwise <literal>bind</literal> is preferable, as it means direct changes to
<filename>/etc/resolv.conf</filename> in the container are not allowed, as it is a read-only bind
mount (but note that if the container has enough privileges, it might simply go ahead and unmount the
bind mount anyway). Note that both if the file is bind mounted and if it is copied no further
propagation of configuration is generally done after the one-time early initialization (this is
because the file is usually updated through copying and renaming). Defaults to
nspawn: add greater control over how /etc/resolv.conf is handled Fixes: #8014 #1781
2018-05-12 22:50:57 +03:00
<literal>auto</literal>.</para></listitem>
</varlistentry>
nspawn: similar to the previous patches, also make /etc/localtime handling more configurable Fixes: #9009
2018-05-17 06:43:03 +03:00
<varlistentry>
<term><option>--timezone=</option></term>
tree-wide: fixes for assorted grammar and spelling issues Fixes #16363. Also includes some changes where I generalized the pattern.
2020-07-06 11:49:59 +03:00
<listitem><para>Configures how <filename>/etc/localtime</filename> inside of the container
(i.e. local timezone synchronization from host to container) shall be handled. Takes one of
<literal>off</literal>, <literal>copy</literal>, <literal>bind</literal>, <literal>symlink</literal>,
<literal>delete</literal> or <literal>auto</literal>. If set to <literal>off</literal> the
<filename>/etc/localtime</filename> file in the container is left as it is included in the image, and
neither modified nor bind mounted over. If set to <literal>copy</literal> the
<filename>/etc/localtime</filename> file of the host is copied into the container. Similarly, if
<literal>bind</literal> is used, the file is bind mounted from the host into the container. If set to
<literal>symlink</literal>, a symlink is created pointing from <filename>/etc/localtime</filename> in
the container to the timezone file in the container that matches the timezone setting on the host. If
set to <literal>delete</literal>, the file in the container is deleted, should it exist. If set to
<literal>auto</literal> and the <filename>/etc/localtime</filename> file of the host is a symlink,
then <literal>symlink</literal> mode is used, and <literal>copy</literal> otherwise, except if the
image is read-only in which case <literal>bind</literal> is used instead. Defaults to
nspawn: similar to the previous patches, also make /etc/localtime handling more configurable Fixes: #9009
2018-05-17 06:43:03 +03:00
<literal>auto</literal>.</para></listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<term><option>--link-journal=</option></term>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<listitem><para>Control whether the container's journal shall
be made visible to the host system. If enabled, allows viewing
the container's journal files from the host (but not vice
versa). Takes one of <literal>no</literal>,
<literal>host</literal>, <literal>try-host</literal>,
<literal>guest</literal>, <literal>try-guest</literal>,
<literal>auto</literal>. If <literal>no</literal>, the journal
is not linked. If <literal>host</literal>, the journal files
are stored on the host file system (beneath
<filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>)
and the subdirectory is bind-mounted into the container at the
same location. If <literal>guest</literal>, the journal files
are stored on the guest file system (beneath
<filename>/var/log/journal/<replaceable>machine-id</replaceable></filename>)
and the subdirectory is symlinked into the host at the same
location. <literal>try-host</literal> and
<literal>try-guest</literal> do the same but do not fail if
the host does not have persistent journaling enabled. If
<literal>auto</literal> (the default), and the right
subdirectory of <filename>/var/log/journal</filename> exists,
it will be bind mounted into the container. If the
subdirectory does not exist, no linking is performed.
Effectively, booting a container once with
<literal>guest</literal> or <literal>host</literal> will link
the journal persistently if further on the default of
<literal>auto</literal> is used.</para>
<para>Note that <option>--link-journal=try-guest</option> is the default if the
<filename>systemd-nspawn@.service</filename> template unit file is used.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<varlistentry>
<term><option>-j</option></term>
<listitem><para>Equivalent to
<option>--link-journal=try-guest</option>.</para></listitem>
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>Mount Options</title>
<variablelist>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--bind=</option></term>
<term><option>--bind-ro=</option></term>
nspawn: permit prefixing of source paths in --bind= and --overlay= with "+" If a source path is prefixed with "+" it is taken relative to the container's root directory instead of the host. This permits easily establishing bind and overlay mounts based on data from the container rather than the host. This also reworks custom_mounts_prepare(), and turns it into two functions: one custom_mount_check_all() that remains in nspawn.c but purely verifies the validity of the custom mounts configured. And one called custom_mount_prepare_all() that actually does the preparation step, sorts the custom mounts, resolves relative paths, and allocates temporary directories as necessary.
2016-11-30 18:02:47 +03:00
<listitem><para>Bind mount a file or directory from the host into the container. Takes one of: a path
nspawn: optionally, automatically allocated --bind=/--overlay source from /var/tmp This extends the --bind= and --overlay= syntax so that an empty string as source/upper directory is taken as request to automatically allocate a temporary directory below /var/tmp, whose lifetime is bound to the nspawn runtime. In combination with the "+" path extension this permits a switch "--overlay=+/var::/var" in order to use the container's shipped /var, combine it with a writable temporary directory and mount it to the runtime /var of the container.
2016-11-30 20:57:42 +03:00
argument — in which case the specified path will be mounted from the host to the same path in the container, or
a colon-separated pair of paths — in which case the first specified path is the source in the host, and the
second path is the destination in the container, or a colon-separated triple of source path, destination path
nspawn: permit prefixing of source paths in --bind= and --overlay= with "+" If a source path is prefixed with "+" it is taken relative to the container's root directory instead of the host. This permits easily establishing bind and overlay mounts based on data from the container rather than the host. This also reworks custom_mounts_prepare(), and turns it into two functions: one custom_mount_check_all() that remains in nspawn.c but purely verifies the validity of the custom mounts configured. And one called custom_mount_prepare_all() that actually does the preparation step, sorts the custom mounts, resolves relative paths, and allocates temporary directories as necessary.
2016-11-30 18:02:47 +03:00
and mount options. The source path may optionally be prefixed with a <literal>+</literal> character. If so, the
nspawn: optionally, automatically allocated --bind=/--overlay source from /var/tmp This extends the --bind= and --overlay= syntax so that an empty string as source/upper directory is taken as request to automatically allocate a temporary directory below /var/tmp, whose lifetime is bound to the nspawn runtime. In combination with the "+" path extension this permits a switch "--overlay=+/var::/var" in order to use the container's shipped /var, combine it with a writable temporary directory and mount it to the runtime /var of the container.
2016-11-30 20:57:42 +03:00
source path is taken relative to the image's root directory. This permits setting up bind mounts within the
container image. The source path may be specified as empty string, in which case a temporary directory below
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
the host's <filename>/var/tmp/</filename> directory is used. It is automatically removed when the container is
nspawn: optionally, automatically allocated --bind=/--overlay source from /var/tmp This extends the --bind= and --overlay= syntax so that an empty string as source/upper directory is taken as request to automatically allocate a temporary directory below /var/tmp, whose lifetime is bound to the nspawn runtime. In combination with the "+" path extension this permits a switch "--overlay=+/var::/var" in order to use the container's shipped /var, combine it with a writable temporary directory and mount it to the runtime /var of the container.
2016-11-30 20:57:42 +03:00
shut down. Mount options are comma-separated and currently, only <option>rbind</option> and
<option>norbind</option> are allowed, controlling whether to create a recursive or a regular bind
mount. Defaults to "rbind". Backslash escapes are interpreted, so <literal>\:</literal> may be used to embed
colons in either path. This option may be specified multiple times for creating multiple independent bind
man: document how nspawn's --bind= and --private-users interact Fixes: #5900
2017-11-16 20:05:42 +03:00
mount points. The <option>--bind-ro=</option> option creates read-only bind mounts.</para>
<para>Note that when this option is used in combination with <option>--private-users</option>, the resulting
mount points will be owned by the <constant>nobody</constant> user. That's because the mount and its files and
directories continue to be owned by the relevant host users and groups, which do not exist in the container,
and thus show up under the wildcard UID 65534 (nobody). If such bind mounts are created, it is recommended to
make them read-only, using <option>--bind-ro=</option>.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
man: document new nspawn --bind-user= feature
2021-05-07 12:44:26 +03:00
<varlistentry>
<term><option>--bind-user=</option></term>
<listitem><para>Binds the home directory of the specified user on the host into the container. Takes
the name of an existing user on the host as argument. May be used multiple times to bind multiple
users into the container. This does three things:</para>
<orderedlist>
<listitem><para>The user's home directory is bind mounted from the host into
<filename>/run/hosts/home/</filename>.</para></listitem>
<listitem><para>An additional UID/GID mapping is added that maps the host user's UID/GID to a
container UID/GID, allocated from the 60514…60577 range.</para></listitem>
<listitem><para>A JSON user and group record is generated in <filename>/run/userdb/</filename> that
describes the mapped user. It contains a minimized representation of the host's user record,
adjusted to the UID/GID and home directory path assigned to the user in the container. The
<citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>
glibc NSS module will pick up these records from there and make them available in the container's
user/group databases.</para></listitem>
</orderedlist>
<para>The combination of the three operations above ensures that it is possible to log into the
host's user account inside the container as if it was local to the container. The user is only mapped
transiently, while the container is running and the mapping itself does not result in persistent
changes to the container (except maybe for generated log messages at login time, and similar). Note
that in particular the UID/GID assignment in the container is not made persistently. If the user is
mapped transiently, it is best to not allow the user to make persistent changes to the container. If
the user leaves files or directories owned by the user, and those UIDs/GIDs are recycled during later
container invocations (possibly with a different <option>--bind-user=</option> mapping), those files
and directories will be accessible to the "new" user.</para>
<para>The user/group record mapping only works if the container contains systemd 249 or newer, with
<command>nss-systemd</command> properly configured in <filename>nsswitch.conf</filename>. See
<citerefentry><refentrytitle>nss-systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry> for
details.</para>
<para>Note that the user record propagated from the host into the container will contain the UNIX
password hash of the user, so that seamless logins in the container are possible. If the container is
less trusted than the host it's hence important to use a strong UNIX password hash function
(e.g. yescrypt or similar, with the <literal>$y$</literal> hash prefix).</para>
<para>When binding a user from the host into the container checks are executed to ensure that the
username is not yet known in the container. Moreover, it is checked that the UID/GID allocated for it
is not currently defined in the user/group databases of the container. Both checks directly access
the container's <filename>/etc/passwd</filename> and <filename>/etc/group</filename>, and thus might
not detect existing accounts in other databases.</para>
<para>This operation is only supported in combination with
<option>--private-users=</option>/<option>-U</option>.</para></listitem>
</varlistentry>
man: document the various new options nspawn learnt
2018-07-31 14:18:55 +03:00
<varlistentry>
<term><option>--inaccessible=</option></term>
<listitem><para>Make the specified path inaccessible in the container. This over-mounts the specified path
(which must exist in the container) with a file node of the same type that is empty and has the most
restrictive access mode supported. This is an effective way to mask files, directories and other file system
objects from the container payload. This option may be used more than once in case all specified paths are
masked.</para></listitem>
</varlistentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<varlistentry>
<term><option>--tmpfs=</option></term>
man: document nspawn's new --volatile=overlay switch
2018-12-21 23:45:46 +03:00
<listitem><para>Mount a tmpfs file system into the container. Takes a single absolute path argument that
specifies where to mount the tmpfs instance to (in which case the directory access mode will be chosen as 0755,
owned by root/root), or optionally a colon-separated pair of path and mount option string that is used for
mounting (in which case the kernel default for access mode and owner will be chosen, unless otherwise
specified). Backslash escapes are interpreted in the path, so <literal>\:</literal> may be used to embed colons
in the path.</para>
<para>Note that this option cannot be used to replace the root file system of the container with a temporary
file system. However, the <option>--volatile=</option> option described below provides similar
functionality, with a focus on implementing stateless operating system images.</para></listitem>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</varlistentry>
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
<varlistentry>
<term><option>--overlay=</option></term>
<term><option>--overlay-ro=</option></term>
<listitem><para>Combine multiple directory trees into one
overlay file system and mount it into the container. Takes a
list of colon-separated paths to the directory trees to
combine and the destination mount point.</para>
man: Document \: escapes in nspawn's --overlay option
2015-06-19 18:24:40 +03:00
<para>Backslash escapes are interpreted in the paths, so
<literal>\:</literal> may be used to embed colons in the paths.
</para>
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
<para>If three or more paths are specified, then the last
specified path is the destination mount point in the
container, all paths specified before refer to directory trees
on the host and are combined in the specified order into one
overlay file system. The left-most path is hence the lowest
directory tree, the second-to-last path the highest directory
tree in the stacking order. If <option>--overlay-ro=</option>
doc: correct punctuation and improve typography in documentation
2014-08-03 09:11:12 +04:00
is used instead of <option>--overlay=</option>, a read-only
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
overlay file system is created. If a writable overlay file
doc: correct punctuation and improve typography in documentation
2014-08-03 09:11:12 +04:00
system is created, all changes made to it are written to the
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
highest directory tree in the stacking order, i.e. the
second-to-last specified.</para>
<para>If only two paths are specified, then the second
specified path is used both as the top-level directory tree in
the stacking order as seen from the host, as well as the mount
point for the overlay file system in the container. At least
two paths have to be specified.</para>
man: use trailing slash on directories in more places
2020-10-05 19:08:21 +03:00
<para>The source paths may optionally be prefixed with <literal>+</literal> character. If so they are
taken relative to the image's root directory. The uppermost source path may also be specified as an
empty string, in which case a temporary directory below the host's <filename>/var/tmp/</filename> is
used. The directory is removed automatically when the container is shut down. This behaviour is
useful in order to make read-only container directories writable while the container is running. For
example, use <literal>--overlay=+/var::/var</literal> in order to automatically overlay a writable
temporary directory on a read-only <filename>/var/</filename> directory.</para>
nspawn: permit prefixing of source paths in --bind= and --overlay= with "+" If a source path is prefixed with "+" it is taken relative to the container's root directory instead of the host. This permits easily establishing bind and overlay mounts based on data from the container rather than the host. This also reworks custom_mounts_prepare(), and turns it into two functions: one custom_mount_check_all() that remains in nspawn.c but purely verifies the validity of the custom mounts configured. And one called custom_mount_prepare_all() that actually does the preparation step, sorts the custom mounts, resolves relative paths, and allocates temporary directories as necessary.
2016-11-30 18:02:47 +03:00
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
<para>For details about overlay file systems, see <ulink
url="https://www.kernel.org/doc/Documentation/filesystems/overlayfs.txt">overlayfs.txt</ulink>. Note
that the semantics of overlay file systems are substantially
different from normal file systems, in particular regarding
reported device and inode information. Device and inode
information may change for a file while it is being written
to, and processes might see out-of-date versions of files at
times. Note that this switch automatically derives the
<literal>workdir=</literal> mount option for the overlay file
system from the top-level directory tree, making it a sibling
of it. It is hence essential that the top-level directory tree
is not a mount point itself (since the working directory must
be on the same file system as the top-most directory
tree). Also note that the <literal>lowerdir=</literal> mount
option receives the paths to stack in the opposite order of
man: document nspawn's new --volatile=overlay switch
2018-12-21 23:45:46 +03:00
this switch.</para>
<para>Note that this option cannot be used to replace the root file system of the container with an overlay
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
file system. However, the <option>--volatile=</option> option described above provides similar functionality,
man: document nspawn's new --volatile=overlay switch
2018-12-21 23:45:46 +03:00
with a focus on implementing stateless operating system images.</para></listitem>
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
</varlistentry>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</variablelist>
nspawn: rework custom mount point order, and add support for overlayfs Previously all bind mount mounts were applied in the order specified, followed by all tmpfs mounts in the order specified. This is problematic, if bind mounts shall be placed within tmpfs mounts. This patch hence reworks the custom mount point logic, and alwas applies them in strict prefix-first order. This means the order of mounts specified on the command line becomes irrelevant, the right operation will always be executed. While we are at it this commit also adds native support for overlayfs mounts, as supported by recent kernels.
2015-05-13 15:04:55 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</refsect2><refsect2>
<title>Input/Output Options</title>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
<variablelist>
man: document the various new options nspawn learnt
2018-07-31 14:18:55 +03:00
<varlistentry>
<term><option>--console=</option><replaceable>MODE</replaceable></term>
man: reorder description of nspawn --console The default value was described at the end of two long paragraphs. Make the first para self contained, and move the description of --console=pipe into the second para.
2019-10-23 11:13:30 +03:00
<listitem><para>Configures how to set up standard input, output and error output for the container
payload, as well as the <filename>/dev/console</filename> device for the container. Takes one of
nspawn: add --console=autopipe mode By default we'll run a container in --console=interactive and --console=read-only mode depending if we are invoked on a tty or not so that the container always gets a /dev/console allocated, i.e is always suitable to run a full init system /as those typically expect a /dev/console to exist). With the new --console=autopipe mode we do something similar, but slightly different: when not invoked on a tty we'll use --console=pipe. This means, if you invoke some tool in a container with this you'll get full inetractivity if you invoke it on a tty but things will also be very nicely pipeable. OTOH you cannot invoke a full init system like this, because you might or might not become a /dev/console this way... Prompted-by: #17070 (I named this "autopipe" rather than "auto" or so, since the default mode probably should be named "auto" one day if we add a name for it, and this is so similar to "auto" except that it uses pipes in the non-tty case).
2020-09-17 17:26:14 +03:00
<option>interactive</option>, <option>read-only</option>, <option>passive</option>,
<option>pipe</option> or <option>autopipe</option>. If <option>interactive</option>, a pseudo-TTY is
allocated and made available as <filename>/dev/console</filename> in the container. It is then
bi-directionally connected to the standard input and output passed to
<command>systemd-nspawn</command>. <option>read-only</option> is similar but only the output of the
container is propagated and no input from the caller is read. If <option>passive</option>, a pseudo
TTY is allocated, but it is not connected anywhere. In <option>pipe</option> mode no pseudo TTY is
allocated, but the standard input, output and error output file descriptors passed to
<command>systemd-nspawn</command> are passed on — as they are — to the container payload, see the
following paragraph. Finally, <option>autopipe</option> mode operates like
<option>interactive</option> when <command>systemd-nspawn</command> is invoked on a terminal, and
like <option>pipe</option> otherwise. Defaults to <option>interactive</option> if
man: document the various new options nspawn learnt
2018-07-31 14:18:55 +03:00
<command>systemd-nspawn</command> is invoked from a terminal, and <option>read-only</option>
man: reorder description of nspawn --console The default value was described at the end of two long paragraphs. Make the first para self contained, and move the description of --console=pipe into the second para.
2019-10-23 11:13:30 +03:00
otherwise.</para>
<para>In <option>pipe</option> mode, <filename>/dev/console</filename> will not exist in the
container. This means that the container payload generally cannot be a full init system as init
systems tend to require <filename>/dev/console</filename> to be available. On the other hand, in this
mode container invocations can be used within shell pipelines. This is because intermediary pseudo
TTYs do not permit independent bidirectional propagation of the end-of-file (EOF) condition, which is
necessary for shell pipelines to work correctly. <emphasis>Note that the <option>pipe</option> mode
should be used carefully</emphasis>, as passing arbitrary file descriptors to less trusted container
payloads might open up unwanted interfaces for access by the container payload. For example, if a
passed file descriptor refers to a TTY of some form, APIs such as <constant>TIOCSTI</constant> may be
used to synthesize input that might be used for escaping the container. Hence <option>pipe</option>
mode should only be used if the payload is sufficiently trusted or when the standard
input/output/error output file descriptors are known safe, for example pipes.</para></listitem>
man: document the various new options nspawn learnt
2018-07-31 14:18:55 +03:00
</varlistentry>
<varlistentry>
<term><option>--pipe</option></term>
<term><option>-P</option></term>
<listitem><para>Equivalent to <option>--console=pipe</option>.</para></listitem>
</varlistentry>
man: document nspawn's new credential switches
2020-07-23 18:43:18 +03:00
</variablelist>
</refsect2><refsect2>
<title>Credentials</title>
<variablelist>
<varlistentry>
<term><option>--load-credential=</option><replaceable>ID</replaceable>:<replaceable>PATH</replaceable></term>
<term><option>--set-credential=</option><replaceable>ID</replaceable>:<replaceable>VALUE</replaceable></term>
man: shorten description of recursive credential passing in nspawn The text suggested that either nspawn or systemd can make use of credentials themselves. In fact they only pass them to children.
2020-08-26 11:42:27 +03:00
<listitem><para>Pass a credential to the container. These two options correspond to the
man: document nspawn's new credential switches
2020-07-23 18:43:18 +03:00
<varname>LoadCredential=</varname> and <varname>SetCredential=</varname> settings in unit files. See
<citerefentry><refentrytitle>systemd.exec</refentrytitle><manvolnum>5</manvolnum></citerefentry> for
details about these concepts, as well as the syntax of the option's arguments.</para>
man: shorten description of recursive credential passing in nspawn The text suggested that either nspawn or systemd can make use of credentials themselves. In fact they only pass them to children.
2020-08-26 11:42:27 +03:00
<para>Note: when <command>systemd-nspawn</command> runs as systemd system service it can propagate
the credentials it received via <varname>LoadCredential=</varname>/<varname>SetCredential=</varname>
to the container payload. A systemd service manager running as PID 1 in the container can further
propagate them to the services it itself starts. It is thus possible to easily propagate credentials
from a parent service manager to a container manager service and from there into its payload. This
can even be done recursively.</para>
<para>In order to embed binary data into the credential data for <option>--set-credential=</option>
use C-style escaping (i.e. <literal>\n</literal> to embed a newline, or <literal>\x00</literal> to
embed a <constant>NUL</constant> byte. Note that the invoking shell might already apply unescaping
man: document in nspawn docs how to make use of the new firstboot/sysusers features
2021-03-11 19:49:18 +03:00
once, hence this might require double escaping!).</para>
<para>The
<citerefentry><refentrytitle>systemd-sysusers.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
and
<citerefentry><refentrytitle>systemd-firstboot</refentrytitle><manvolnum>1</manvolnum></citerefentry>
services read credentials configured this way for the purpose of configuring the container's root
user's password and shell, as well as system locale, keymap and timezone during the first boot
process of the container. This is particularly useful in combination with
<option>--volatile=yes</option> where every single boot appears as first boot, since configuration
applied to <filename>/etc/</filename> is lost on container reboot cycles. See the respective man
pages for details. Example:</para>
<programlisting># systemd-nspawn -i image.raw \
--volatile=yes \
--set-credential=firstboot.locale:de_DE.UTF-8 \
--set-credential=passwd.hashed-password.root:'$y$j9T$yAuRJu1o5HioZAGDYPU5d.$F64ni6J2y2nNQve90M/p0ZP0ECP/qqzipNyaY9fjGpC' \
-b</programlisting>
<para>The above command line will invoke the specified image file <filename>image.raw</filename> in
volatile mode, i.e with an empty <filename>/etc/</filename> and <filename>/var/</filename>, so that
the container's payload recognizes this as first boot condition, and will invoke
<filename>systemd-firstboot.service</filename>, which then read the two passed credentials to
configure the system's initial locale and root password.</para>
</listitem>
man: document nspawn's new credential switches
2020-07-23 18:43:18 +03:00
</varlistentry>
</variablelist>
</refsect2><refsect2>
<title>Other</title>
<variablelist>
nspawn: add --no-pager switch It only matters for --help.
2019-03-21 17:24:50 +03:00
<xi:include href="standard-options.xml" xpointer="no-pager" />
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
man: adjust nspawn man page to follow same section/order as --help text No other changes, just some reshuffling and adding of section headers (well, admittedly, I changed some "see above" and "see below" in the text to match the new order.)
2019-03-21 15:27:48 +03:00
</refsect2>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</refsect1>
man: rename less-variables→common-variables Some are not about less, e.g. $SYSTEMD_URLIFY.
2021-02-28 14:18:25 +03:00
<xi:include href="common-variables.xml" />
nspawn: add --no-pager switch It only matters for --help.
2019-03-21 17:24:50 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<refsect1>
<title>Examples</title>
<example>
man: mention how to provision Ubuntu and Tanglu for nspawn (#7359) Also add urls. Urls are nice.
2017-11-16 15:40:35 +03:00
<title>Download a
<ulink url="https://getfedora.org">Fedora</ulink> image and start a shell in it</title>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
man: break long lines and update Fedora versions We should try to keep the unbreakable lines below 80 columns. It's not always possible of course. Also, use the dl.fp.o alias instead of a specific mirror.
2017-02-09 04:13:57 +03:00
<programlisting># machinectl pull-raw --verify=no \
man: save pull-raw example file without underscores Destination file needs to be a valid hostname and underscores are not valid hostname characters. Closes #13542
2019-11-06 03:04:27 +03:00
https://download.fedoraproject.org/pub/fedora/linux/releases/&fedora_latest_version;/Cloud/x86_64/images/Fedora-Cloud-Base-&fedora_latest_version;-&fedora_cloud_release;.x86_64.raw.xz \
Fedora-Cloud-Base-&fedora_latest_version;-&fedora_cloud_release;.x86-64
# systemd-nspawn -M Fedora-Cloud-Base-&fedora_latest_version;-&fedora_cloud_release;.x86-64</programlisting>
man: document new download magic
2015-01-22 17:12:11 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<para>This downloads an image using
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
and opens a shell in it.</para>
</example>
man: document new download magic
2015-01-22 17:12:11 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<example>
<title>Build and boot a minimal Fedora distribution in a container</title>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
man: use entities for fedora number and update URL Fedora 28 is out already, let's advertise it. While at it, drop "container" from "f28container" — it's a subdirectory under /var/lib/machines, it's pretty obvious that's it a container. To make the switch easier in the future, define the number as an entity.
2018-06-05 10:15:19 +03:00
<programlisting># dnf -y --releasever=&fedora_latest_version; --installroot=/var/lib/machines/f&fedora_latest_version; \
man: break long lines and update Fedora versions We should try to keep the unbreakable lines below 80 columns. It's not always possible of course. Also, use the dl.fp.o alias instead of a specific mirror.
2017-02-09 04:13:57 +03:00
--disablerepo='*' --enablerepo=fedora --enablerepo=updates install \
man,mkosi: use glibc-minimal-langpack for Fedora This saves ~24MB of space, see https://fedoraproject.org/wiki/Changes/Remove_glibc-langpacks-all_from_buildroot.
2020-03-03 16:50:58 +03:00
systemd passwd dnf fedora-release vim-minimal glibc-minimal-langpack
man: use entities for fedora number and update URL Fedora 28 is out already, let's advertise it. While at it, drop "container" from "f28container" — it's a subdirectory under /var/lib/machines, it's pretty obvious that's it a container. To make the switch easier in the future, define the number as an entity.
2018-06-05 10:15:19 +03:00
# systemd-nspawn -bD /var/lib/machines/f&fedora_latest_version;</programlisting>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<para>This installs a minimal Fedora distribution into the
man: change noindex="true" to index="false" We nowadays prefer positive options over negative.
2019-11-21 22:22:12 +03:00
directory <filename index="false">/var/lib/machines/f&fedora_latest_version;</filename>
tree-wide: fixes for assorted grammar and spelling issues Fixes #16363. Also includes some changes where I generalized the pattern.
2020-07-06 11:49:59 +03:00
and then boots that OS in a namespace container. Because the installation
man: recommend using /var/lib/machines in systemd-nspawn(1) Also update the instruction to latest Fedora version.
2017-10-18 10:39:30 +03:00
is located underneath the standard <filename>/var/lib/machines/</filename>
directory, it is also possible to start the machine using
man: use entities for fedora number and update URL Fedora 28 is out already, let's advertise it. While at it, drop "container" from "f28container" — it's a subdirectory under /var/lib/machines, it's pretty obvious that's it a container. To make the switch easier in the future, define the number as an entity.
2018-06-05 10:15:19 +03:00
<command>systemd-nspawn -M f&fedora_latest_version;</command>.</para>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</example>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<example>
<title>Spawn a shell in a container of a minimal Debian unstable distribution</title>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
man: drop --arch from debootstrap invocation Nowadays people use systemd on many different architectures, so we shouldn't presuppose that they are using amd64. debootstrap defaults to the native architecture and this should be good enough.
2018-01-03 17:57:11 +03:00
<programlisting># debootstrap unstable ~/debian-tree/
man: rework nspawn man page to suggest yum --installroot instead of mock
2012-04-24 15:14:27 +04:00
# systemd-nspawn -D ~/debian-tree/</programlisting>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<para>This installs a minimal Debian unstable distribution into
the directory <filename>~/debian-tree/</filename> and then
tree-wide: fixes for assorted grammar and spelling issues Fixes #16363. Also includes some changes where I generalized the pattern.
2020-07-06 11:49:59 +03:00
spawns a shell from this image in a namespace container.</para>
man: mention how to provision Ubuntu and Tanglu for nspawn (#7359) Also add urls. Urls are nice.
2017-11-16 15:40:35 +03:00
<para><command>debootstrap</command> supports
<ulink url="https://www.debian.org">Debian</ulink>,
<ulink url="https://www.ubuntu.com">Ubuntu</ulink>,
and <ulink url="https://www.tanglu.org">Tanglu</ulink>
out of the box, so the same command can be used to install any of those. For other
distributions from the Debian family, a mirror has to be specified, see
<citerefentry project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>.
</para>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</example>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<example>
man: mention how to provision Ubuntu and Tanglu for nspawn (#7359) Also add urls. Urls are nice.
2017-11-16 15:40:35 +03:00
<title>Boot a minimal
<ulink url="https://www.archlinux.org">Arch Linux</ulink> distribution in a container</title>
man: add Arch Linux entry to systemd-nspawn(5) Archlinux has a similar tool to debbotstrap in the arch-install-scripts package that will install to a specified directory. This is generally used for installation, so the -d flag must be passed to tell it to install to a non-mountpoint directory.
2013-01-26 21:15:32 +04:00
systemd-nspawn(1): update example section Remove the retired flag -d from Example 4. "Boot a minimal Arch Linux distribution in a container". It has been retired here: https://git.archlinux.org/arch-install-scripts.git/commit/pacstrap.in?id=0af6884aca68dcb7eed0b85fbc2960903df3d968
2019-06-25 11:28:19 +03:00
<programlisting># pacstrap -c ~/arch-tree/ base
man: add Arch Linux entry to systemd-nspawn(5) Archlinux has a similar tool to debbotstrap in the arch-install-scripts package that will install to a specified directory. This is generally used for installation, so the -d flag must be passed to tell it to install to a non-mountpoint directory.
2013-01-26 21:15:32 +04:00
# systemd-nspawn -bD ~/arch-tree/</programlisting>
treewide: Correct typos and spell plural of bus consistent
2015-05-11 14:49:29 +03:00
<para>This installs a minimal Arch Linux distribution into the
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
directory <filename>~/arch-tree/</filename> and then boots an OS
in a namespace container in it.</para>
</example>
man: add Arch Linux entry to systemd-nspawn(5) Archlinux has a similar tool to debbotstrap in the arch-install-scripts package that will install to a specified directory. This is generally used for installation, so the -d flag must be passed to tell it to install to a non-mountpoint directory.
2013-01-26 21:15:32 +04:00
man: add zypper instructions for systemd-nspawn v2: - add -c and update the list of packages v3: - link to a man page on mankier.com
2017-07-02 20:37:27 +03:00
<example>
man: mention how to provision Ubuntu and Tanglu for nspawn (#7359) Also add urls. Urls are nice.
2017-11-16 15:40:35 +03:00
<title>Install the
<ulink url="https://software.opensuse.org/distributions/tumbleweed">OpenSUSE Tumbleweed</ulink>
rolling distribution</title>
man: add zypper instructions for systemd-nspawn v2: - add -c and update the list of packages v3: - link to a man page on mankier.com
2017-07-02 20:37:27 +03:00
<programlisting># zypper --root=/var/lib/machines/tumbleweed ar -c \
https://download.opensuse.org/tumbleweed/repo/oss tumbleweed
# zypper --root=/var/lib/machines/tumbleweed refresh
# zypper --root=/var/lib/machines/tumbleweed install --no-recommends \
systemd shadow zypper openSUSE-release vim
# systemd-nspawn -M tumbleweed passwd root
# systemd-nspawn -M tumbleweed -b</programlisting>
</example>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<example>
nspawn: add fallback top normal copy/reflink when we cannot btrfs snapshot Given that other file systems (notably: xfs) support reflinks these days, let's extend the file system snapshotting logic to fall back to plan copies or reflinks when full btrfs subvolume snapshots are not available. This essentially makes "systemd-nspawn --ephemeral" and "systemd-nspawn --template=" available on non-btrfs subvolumes. Of course, both operations will still be slower on non-btrfs than on btrfs (simply because reflinking each file individually in a directory tree is still slower than doing this in one step for a whole subvolume), but it's probably good enough for many cases, and we should provide the users with the tools, they have to figure out what's good for them. Note that "machinectl clone" already had a fallback like this in place, this patch generalizes this, and adds similar support to our other cases.
2016-11-21 22:02:43 +03:00
<title>Boot into an ephemeral snapshot of the host system</title>
man: add another nspawn example Taken from https://bugs.freedesktop.org/show_bug.cgi?id=68369.
2013-12-13 08:14:48 +04:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<programlisting># systemd-nspawn -D / -xb</programlisting>
man: add another nspawn example Taken from https://bugs.freedesktop.org/show_bug.cgi?id=68369.
2013-12-13 08:14:48 +04:00
nspawn: add fallback top normal copy/reflink when we cannot btrfs snapshot Given that other file systems (notably: xfs) support reflinks these days, let's extend the file system snapshotting logic to fall back to plan copies or reflinks when full btrfs subvolume snapshots are not available. This essentially makes "systemd-nspawn --ephemeral" and "systemd-nspawn --template=" available on non-btrfs subvolumes. Of course, both operations will still be slower on non-btrfs than on btrfs (simply because reflinking each file individually in a directory tree is still slower than doing this in one step for a whole subvolume), but it's probably good enough for many cases, and we should provide the users with the tools, they have to figure out what's good for them. Note that "machinectl clone" already had a fallback like this in place, this patch generalizes this, and adds similar support to our other cases.
2016-11-21 22:02:43 +03:00
<para>This runs a copy of the host system in a snapshot which is removed immediately when the container
exits. All file system changes made during runtime will be lost on shutdown, hence.</para>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</example>
man: add another nspawn example Taken from https://bugs.freedesktop.org/show_bug.cgi?id=68369.
2013-12-13 08:14:48 +04:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<example>
<title>Run a container with SELinux sandbox security contexts</title>
Add SELinux support to systemd-nspawn This patch adds to new options: -Z PROCESS_LABEL This specifies the process label to run on processes run within the container. -L FILE_LABEL The file label to assign to memory file systems created within the container. For example if you wanted to wrap an container with SELinux sandbox labels, you could execute a command line the following chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container systemd-nspawn -L system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -Z system_u:system_r:svirt_lxc_net_t:s0:c0,c1 -D /srv/container /bin/sh
2014-01-31 01:28:02 +04:00
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<programlisting># chcon system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 -R /srv/container
man: break long lines and update Fedora versions We should try to keep the unbreakable lines below 80 columns. It's not always possible of course. Also, use the dl.fp.o alias instead of a specific mirror.
2017-02-09 04:13:57 +03:00
# systemd-nspawn -L system_u:object_r:svirt_sandbox_file_t:s0:c0,c1 \
-Z system_u:system_r:svirt_lxc_net_t:s0:c0,c1 -D /srv/container /bin/sh</programlisting>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</example>
nspawn: Add support for sysroot pivoting (#5258) Add a new --pivot-root argument to systemd-nspawn, which specifies a directory to pivot to / inside the container; while the original / is pivoted to another specified directory (if provided). This adds support for booting container images which may contain several bootable sysroots, as is common with OSTree disk images. When these disk images are booted on real hardware, ostree-prepare-root is run in conjunction with sysroot.mount in the initramfs to achieve the same results.
2017-02-08 18:54:31 +03:00
<example>
<title>Run a container with an OSTree deployment</title>
man: break long lines and update Fedora versions We should try to keep the unbreakable lines below 80 columns. It's not always possible of course. Also, use the dl.fp.o alias instead of a specific mirror.
2017-02-09 04:13:57 +03:00
<programlisting># systemd-nspawn -b -i ~/image.raw \
--pivot-root=/ostree/deploy/$OS/deploy/$CHECKSUM:/sysroot \
--bind=+/sysroot/ostree/deploy/$OS/var:/var</programlisting>
nspawn: Add support for sysroot pivoting (#5258) Add a new --pivot-root argument to systemd-nspawn, which specifies a directory to pivot to / inside the container; while the original / is pivoted to another specified directory (if provided). This adds support for booting container images which may contain several bootable sysroots, as is common with OSTree disk images. When these disk images are booted on real hardware, ostree-prepare-root is run in conjunction with sysroot.mount in the initramfs to achieve the same results.
2017-02-08 18:54:31 +03:00
</example>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</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>,
nspawn: add new .nspawn files for container settings .nspawn fiels are simple settings files that may accompany container images and directories and contain settings otherwise passed on the nspawn command line. This provides an efficient way to attach execution data directly to containers.
2015-09-06 02:22:14 +03:00
<citerefentry><refentrytitle>systemd.nspawn</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<citerefentry project='man-pages'><refentrytitle>chroot</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='mankier'><refentrytitle>dnf</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>debootstrap</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry project='archlinux'><refentrytitle>pacman</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
man: add zypper instructions for systemd-nspawn v2: - add -c and update the list of packages v3: - link to a man page on mankier.com
2017-07-02 20:37:27 +03:00
<citerefentry project='mankier'><refentrytitle>zypper</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
<citerefentry><refentrytitle>systemd.slice</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
man: fix a bunch of links All hail linkchecker!
2015-03-14 05:22:39 +03:00
<citerefentry project='man-pages'><refentrytitle>btrfs</refentrytitle><manvolnum>8</manvolnum></citerefentry>
Reindent man pages to 2ch
2015-02-04 05:14:13 +03:00
</para>
</refsect1>
man: document systemd-nspawn
2011-03-15 22:51:41 +03:00
</refentry>
Copy Permalink