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systemd/man/machinectl.xml
Zbigniew Jędrzejewski-Szmek 855005230b machinectl: add --value option
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<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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Copyright 2013 Zbigniew Jędrzejewski-Szmek
systemd is free software; you can redistribute it and/or modify it
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<refentry id="machinectl" conditional='ENABLE_MACHINED'
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>machinectl</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>Developer</contrib>
<firstname>Lennart</firstname>
<surname>Poettering</surname>
<email>lennart@poettering.net</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>machinectl</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>machinectl</refname>
<refpurpose>Control the systemd machine manager</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>machinectl</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="req">COMMAND</arg>
<arg choice="opt" rep="repeat">NAME</arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>machinectl</command> may be used to introspect and
control the state of the
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
virtual machine and container registration manager
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para>
<para><command>machinectl</command> may be used to execute
operations on machines and images. Machines in this sense are
considered running instances of:</para>
<itemizedlist>
<listitem><para>Virtual Machines (VMs) that virtualize hardware
to run full operating system (OS) instances (including their kernels)
in a virtualized environment on top of the host OS.</para></listitem>
<listitem><para>Containers that share the hardware and
OS kernel with the host OS, in order to run
OS userspace instances on top the host OS.</para></listitem>
<listitem><para>The host system itself</para></listitem>
</itemizedlist>
<para>Machines are identified by names that follow the same rules
as UNIX and DNS host names, for details, see below. Machines are
instantiated from disk or file system images that frequently — but not
necessarily — carry the same name as machines running from
them. Images in this sense are considered:</para>
<itemizedlist>
<listitem><para>Directory trees containing an OS, including its
top-level directories <filename>/usr</filename>,
<filename>/etc</filename>, and so on.</para></listitem>
<listitem><para>btrfs subvolumes containing OS trees, similar to
normal directory trees.</para></listitem>
<listitem><para>Binary "raw" disk images containing MBR or GPT
partition tables and Linux file system partitions.</para></listitem>
<listitem><para>The file system tree of the host OS itself.</para></listitem>
</itemizedlist>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<varlistentry>
<term><option>-p</option></term>
<term><option>--property=</option></term>
<listitem><para>When showing machine or image properties,
limit the output to certain properties as specified by the
argument. If not specified, all set properties are shown. The
argument should be a property name, such as
<literal>Name</literal>. If specified more than once, all
properties with the specified names are
shown.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>-a</option></term>
<term><option>--all</option></term>
<listitem><para>When showing machine or image properties, show
all properties regardless of whether they are set or
not.</para>
<para>When listing VM or container images, do not suppress
images beginning in a dot character
(<literal>.</literal>).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--value</option></term>
<listitem><para>When printing properties with <command>show</command>, only print the value,
and skip the property name and <literal>=</literal>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>-l</option></term>
<term><option>--full</option></term>
<listitem><para>Do not ellipsize process tree entries.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>--no-ask-password</option></term>
<listitem><para>Do not query the user for authentication for
privileged operations.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--kill-who=</option></term>
<listitem><para>When used with <command>kill</command>, choose
which processes to kill. Must be one of
<option>leader</option>, or <option>all</option> to select
whether to kill only the leader process of the machine or all
processes of the machine. If omitted, defaults to
<option>all</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>-s</option></term>
<term><option>--signal=</option></term>
<listitem><para>When used with <command>kill</command>, choose
which signal to send to selected processes. Must be one of the
well-known signal specifiers, such as
<constant>SIGTERM</constant>, <constant>SIGINT</constant> or
<constant>SIGSTOP</constant>. If omitted, defaults to
<constant>SIGTERM</constant>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--uid=</option></term>
<listitem><para>When used with the <command>shell</command>
command, chooses the user ID to open the interactive shell
session as. If this switch is not specified, defaults to
<literal>root</literal>. Note that this switch is not
supported for the <command>login</command> command (see
below).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--setenv=</option></term>
<listitem><para>When used with the <command>shell</command>
command, sets an environment variable to pass to the executed
shell. Takes a pair of environment variable name and value,
separated by <literal>=</literal> as argument. This switch
may be used multiple times to set multiple environment
variables. Note that this switch is not supported for the
<command>login</command> command (see
below).</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--mkdir</option></term>
<listitem><para>When used with <command>bind</command>, creates
the destination directory before applying the bind
mount.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--read-only</option></term>
<listitem><para>When used with <command>bind</command>, applies
a read-only bind mount.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>-n</option></term>
<term><option>--lines=</option></term>
<listitem><para>When used with <command>status</command>,
controls the number of journal lines to show, counting from
the most recent ones. Takes a positive integer argument.
Defaults to 10.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><option>-o</option></term>
<term><option>--output=</option></term>
<listitem><para>When used with <command>status</command>,
controls the formatting of the journal entries that are shown.
For the available choices, see
<citerefentry><refentrytitle>journalctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
Defaults to <literal>short</literal>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--verify=</option></term>
<listitem><para>When downloading a container or VM image,
specify whether the image shall be verified before it is made
available. Takes one of <literal>no</literal>,
<literal>checksum</literal> and <literal>signature</literal>.
If <literal>no</literal>, no verification is done. If
<literal>checksum</literal> is specified, the download is
checked for integrity after the transfer is complete, but no
signatures are verified. If <literal>signature</literal> is
specified, the checksum is verified and the image's signature
is checked against a local keyring of trustable vendors. It is
strongly recommended to set this option to
<literal>signature</literal> if the server and protocol
support this. Defaults to
<literal>signature</literal>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--force</option></term>
<listitem><para>When downloading a container or VM image, and
a local copy by the specified local machine name already
exists, delete it first and replace it by the newly downloaded
image.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--format=</option></term>
<listitem><para>When used with the <option>export-tar</option>
or <option>export-raw</option> commands, specifies the
compression format to use for the resulting file. Takes one of
<literal>uncompressed</literal>, <literal>xz</literal>,
<literal>gzip</literal>, <literal>bzip2</literal>. By default,
the format is determined automatically from the image file
name passed.</para></listitem>
</varlistentry>
<xi:include href="user-system-options.xml" xpointer="host" />
<xi:include href="user-system-options.xml" xpointer="machine" />
<xi:include href="standard-options.xml" xpointer="no-pager" />
<xi:include href="standard-options.xml" xpointer="no-legend" />
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</refsect1>
<refsect1>
<title>Commands</title>
<para>The following commands are understood:</para>
<refsect2><title>Machine Commands</title><variablelist>
<varlistentry>
<term><command>list</command></term>
<listitem><para>List currently running (online) virtual
machines and containers. To enumerate machine images that can
be started, use <command>list-images</command> (see
below). Note that this command hides the special
<literal>.host</literal> machine by default. Use the
<option>--all</option> switch to show it.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>status</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Show runtime status information about
one or more virtual machines and containers, followed by the
most recent log data from the journal. This function is
intended to generate human-readable output. If you are looking
for computer-parsable output, use <command>show</command>
instead. Note that the log data shown is reported by the
virtual machine or container manager, and frequently contains
console output of the machine, but not necessarily journal
contents of the machine itself.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>show</command> [<replaceable>NAME</replaceable>...]</term>
<listitem><para>Show properties of one or more registered
virtual machines or containers or the manager itself. If no
argument is specified, properties of the manager will be
shown. If an NAME is specified, properties of this virtual
machine or container are shown. By default, empty properties
are suppressed. Use <option>--all</option> to show those too.
To select specific properties to show, use
<option>--property=</option>. This command is intended to be
used whenever computer-parsable output is required, and does
not print the cgroup tree or journal entries. Use
<command>status</command> if you are looking for formatted
human-readable output.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>start</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Start a container as a system service, using
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
This starts <filename>systemd-nspawn@.service</filename>,
instantiated for the specified machine name, similar to the
effect of <command>systemctl start</command> on the service
name. <command>systemd-nspawn</command> looks for a container
image by the specified name in
<filename>/var/lib/machines/</filename> (and other search
paths, see below) and runs it. Use
<command>list-images</command> (see below) for listing
available container images to start.</para>
<para>Note that
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
also interfaces with a variety of other container and VM
managers, <command>systemd-nspawn</command> is just one
implementation of it. Most of the commands available in
<command>machinectl</command> may be used on containers or VMs
controlled by other managers, not just
<command>systemd-nspawn</command>. Starting VMs and container
images on those managers requires manager-specific
tools.</para>
<para>To interactively start a container on the command line
with full access to the container's console, please invoke
<command>systemd-nspawn</command> directly. To stop a running
container use <command>machinectl poweroff</command>, see
below.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>login</command> [<replaceable>NAME</replaceable>]</term>
<listitem><para>Open an interactive terminal login session in
a container or on the local host. If an argument is supplied,
it refers to the container machine to connect to. If none is
specified, or the container name is specified as the empty
string, or the special machine name <literal>.host</literal>
(see below) is specified, the connection is made to the local
host instead. This will create a TTY connection to a specific
container or the local host and asks for the execution of a
getty on it. Note that this is only supported for containers
running
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
as init system.</para>
<para>This command will open a full login prompt on the
container or the local host, which then asks for username and
password. Use <command>shell</command> (see below) or
<citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>
with the <option>--machine=</option> switch to directly invoke
a single command, either interactively or in the
background.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>shell</command> [[<replaceable>NAME</replaceable>@]<replaceable>NAME</replaceable> [<replaceable>PATH</replaceable> [<replaceable>ARGUMENTS</replaceable>...]]] </term>
<listitem><para>Open an interactive shell session in a
container or on the local host. The first argument refers to
the container machine to connect to. If none is specified, or
the machine name is specified as the empty string, or the
special machine name <literal>.host</literal> (see below) is
specified, the connection is made to the local host
instead. This works similar to <command>login</command> but
immediately invokes a user process. This command runs the
specified executable with the specified arguments, or
<filename>/bin/sh</filename> if none is specified. By default,
opens a <literal>root</literal> shell, but by using
<option>--uid=</option>, or by prefixing the machine name with
a username and an <literal>@</literal> character, a different
user may be selected. Use <option>--setenv=</option> to set
environment variables for the executed process.</para>
<para>When using the <command>shell</command> command without
arguments, (thus invoking the executed shell or command on the
local host), it is in many ways similar to a <citerefentry
project='die-net'><refentrytitle>su</refentrytitle><manvolnum>1</manvolnum></citerefentry>
session, but, unlike <command>su</command>, completely isolates
the new session from the originating session, so that it
shares no process or session properties, and is in a clean and
well-defined state. It will be tracked in a new utmp, login,
audit, security and keyring session, and will not inherit any
environment variables or resource limits, among other
properties.</para>
<para>Note that
<citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>
may be used in place of the <command>shell</command> command,
and allows more detailed, low-level configuration of the
invoked unit. However, it is frequently more privileged than
the <command>shell</command> command.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>enable</command> <replaceable>NAME</replaceable>...</term>
<term><command>disable</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Enable or disable a container as a system
service to start at system boot, using
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
This enables or disables
<filename>systemd-nspawn@.service</filename>, instantiated for
the specified machine name, similar to the effect of
<command>systemctl enable</command> or <command>systemctl
disable</command> on the service name.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>poweroff</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Power off one or more containers. This will
trigger a reboot by sending SIGRTMIN+4 to the container's init
process, which causes systemd-compatible init systems to shut
down cleanly. This operation does not work on containers that
do not run a
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>-compatible
init system, such as sysvinit. Use
<command>terminate</command> (see below) to immediately
terminate a container or VM, without cleanly shutting it
down.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>reboot</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Reboot one or more containers. This will
trigger a reboot by sending SIGINT to the container's init
process, which is roughly equivalent to pressing Ctrl+Alt+Del
on a non-containerized system, and is compatible with
containers running any system manager.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>terminate</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Immediately terminates a virtual machine or
container, without cleanly shutting it down. This kills all
processes of the virtual machine or container and deallocates
all resources attached to that instance. Use
<command>poweroff</command> to issue a clean shutdown
request.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>kill</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Send a signal to one or more processes of the
virtual machine or container. This means processes as seen by
the host, not the processes inside the virtual machine or
container. Use <option>--kill-who=</option> to select which
process to kill. Use <option>--signal=</option> to select the
signal to send.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>bind</command> <replaceable>NAME</replaceable> <replaceable>PATH</replaceable> [<replaceable>PATH</replaceable>]</term>
<listitem><para>Bind mounts a directory from the host into the
specified container. The first directory argument is the
source directory on the host, the second directory argument
is the destination directory in the container. When the
latter is omitted, the destination path in the container is
the same as the source path on the host. When combined with
the <option>--read-only</option> switch, a ready-only bind
mount is created. When combined with the
<option>--mkdir</option> switch, the destination path is first
created before the mount is applied. Note that this option is
currently only supported for
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
containers.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>copy-to</command> <replaceable>NAME</replaceable> <replaceable>PATH</replaceable> [<replaceable>PATH</replaceable>]</term>
<listitem><para>Copies files or directories from the host
system into a running container. Takes a container name,
followed by the source path on the host and the destination
path in the container. If the destination path is omitted, the
same as the source path is used.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>copy-from</command> <replaceable>NAME</replaceable> <replaceable>PATH</replaceable> [<replaceable>PATH</replaceable>]</term>
<listitem><para>Copies files or directories from a container
into the host system. Takes a container name, followed by the
source path in the container the destination path on the host.
If the destination path is omitted, the same as the source path
is used.</para></listitem>
</varlistentry>
</variablelist></refsect2>
<refsect2><title>Image Commands</title><variablelist>
<varlistentry>
<term><command>list-images</command></term>
<listitem><para>Show a list of locally installed container and
VM images. This enumerates all raw disk images and container
directories and subvolumes in
<filename>/var/lib/machines/</filename> (and other search
paths, see below). Use <command>start</command> (see above) to
run a container off one of the listed images. Note that, by
default, containers whose name begins with a dot
(<literal>.</literal>) are not shown. To show these too,
specify <option>--all</option>. Note that a special image
<literal>.host</literal> always implicitly exists and refers
to the image the host itself is booted from.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>image-status</command> [<replaceable>NAME</replaceable>...]</term>
<listitem><para>Show terse status information about one or
more container or VM images. This function is intended to
generate human-readable output. Use
<command>show-image</command> (see below) to generate
computer-parsable output instead.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>show-image</command> [<replaceable>NAME</replaceable>...]</term>
<listitem><para>Show properties of one or more registered
virtual machine or container images, or the manager itself. If
no argument is specified, properties of the manager will be
shown. If an NAME is specified, properties of this virtual
machine or container image are shown. By default, empty
properties are suppressed. Use <option>--all</option> to show
those too. To select specific properties to show, use
<option>--property=</option>. This command is intended to be
used whenever computer-parsable output is required. Use
<command>image-status</command> if you are looking for
formatted human-readable output.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>clone</command> <replaceable>NAME</replaceable> <replaceable>NAME</replaceable></term>
<listitem><para>Clones a container or VM image. The
arguments specify the name of the image to clone and the name
of the newly cloned image. Note that plain directory container
images are cloned into subvolume images with this command.
Note that cloning a container or VM image is optimized for
btrfs file systems, and might not be efficient on others, due
to file system limitations.</para>
<para>Note that this command leaves host name, machine ID and
all other settings that could identify the instance
unmodified. The original image and the cloned copy will hence
share these credentials, and it might be necessary to manually
change them in the copy.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>rename</command> <replaceable>NAME</replaceable> <replaceable>NAME</replaceable></term>
<listitem><para>Renames a container or VM image. The
arguments specify the name of the image to rename and the new
name of the image.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>read-only</command> <replaceable>NAME</replaceable> [<replaceable>BOOL</replaceable>]</term>
<listitem><para>Marks or (unmarks) a container or VM image
read-only. Takes a VM or container image name, followed by a
boolean as arguments. If the boolean is omitted, positive is
implied, i.e. the image is marked read-only.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>remove</command> <replaceable>NAME</replaceable>...</term>
<listitem><para>Removes one or more container or VM images.
The special image <literal>.host</literal>, which refers to
the host's own directory tree, may not be
removed.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>set-limit</command> [<replaceable>NAME</replaceable>] <replaceable>BYTES</replaceable></term>
<listitem><para>Sets the maximum size in bytes that a specific
container or VM image, or all images, may grow up to on disk
(disk quota). Takes either one or two parameters. The first,
optional parameter refers to a container or VM image name. If
specified, the size limit of the specified image is changed. If
omitted, the overall size limit of the sum of all images stored
locally is changed. The final argument specifies the size
limit in bytes, possibly suffixed by the usual K, M, G, T
units. If the size limit shall be disabled, specify
<literal>-</literal> as size.</para>
<para>Note that per-container size limits are only supported
on btrfs file systems. Also note that, if
<command>set-limit</command> is invoked without an image
parameter, and <filename>/var/lib/machines</filename> is
empty, and the directory is not located on btrfs, a btrfs
loopback file is implicitly created as
<filename>/var/lib/machines.raw</filename> with the given
size, and mounted to
<filename>/var/lib/machines</filename>. The size of the
loopback may later be readjusted with
<command>set-limit</command>, as well. If such a
loopback-mounted <filename>/var/lib/machines</filename>
directory is used, <command>set-limit</command> without an image
name alters both the quota setting within the file system as
well as the loopback file and file system size
itself.</para></listitem>
</varlistentry>
</variablelist></refsect2>
<refsect2><title>Image Transfer Commands</title><variablelist>
<varlistentry>
<term><command>pull-tar</command> <replaceable>URL</replaceable> [<replaceable>NAME</replaceable>]</term>
<listitem><para>Downloads a <filename>.tar</filename>
container image from the specified URL, and makes it available
under the specified local machine name. The URL must be of
type <literal>http://</literal> or
<literal>https://</literal>, and must refer to a
<filename>.tar</filename>, <filename>.tar.gz</filename>,
<filename>.tar.xz</filename> or <filename>.tar.bz2</filename>
archive file. If the local machine name is omitted, it
is automatically derived from the last component of the URL,
with its suffix removed.</para>
<para>The image is verified before it is made available,
unless <option>--verify=no</option> is specified. Verification
is done via SHA256SUMS and SHA256SUMS.gpg files that need to
be made available on the same web server, under the same URL
as the <filename>.tar</filename> file, but with the last
component (the filename) of the URL replaced. With
<option>--verify=checksum</option>, only the SHA256 checksum
for the file is verified, based on the
<filename>SHA256SUMS</filename> file. With
<option>--verify=signature</option>, the SHA256SUMS file is
first verified with detached GPG signature file
<filename>SHA256SUMS.gpg</filename>. The public key for this
verification step needs to be available in
<filename>/usr/lib/systemd/import-pubring.gpg</filename> or
<filename>/etc/systemd/import-pubring.gpg</filename>.</para>
<para>The container image will be downloaded and stored in a
read-only subvolume in
<filename>/var/lib/machines/</filename> that is named after
the specified URL and its HTTP etag. A writable snapshot is
then taken from this subvolume, and named after the specified
local name. This behavior ensures that creating multiple
container instances of the same URL is efficient, as multiple
downloads are not necessary. In order to create only the
read-only image, and avoid creating its writable snapshot,
specify <literal>-</literal> as local machine name.</para>
<para>Note that the read-only subvolume is prefixed with
<filename>.tar-</filename>, and is thus not shown by
<command>list-images</command>, unless <option>--all</option>
is passed.</para>
<para>Note that pressing C-c during execution of this command
will not abort the download. Use
<command>cancel-transfer</command>, described
below.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>pull-raw</command> <replaceable>URL</replaceable> [<replaceable>NAME</replaceable>]</term>
<listitem><para>Downloads a <filename>.raw</filename>
container or VM disk image from the specified URL, and makes
it available under the specified local machine name. The URL
must be of type <literal>http://</literal> or
<literal>https://</literal>. The container image must either
be a <filename>.qcow2</filename> or raw disk image, optionally
compressed as <filename>.gz</filename>,
<filename>.xz</filename>, or <filename>.bz2</filename>. If the
local machine name is omitted, it is automatically
derived from the last component of the URL, with its suffix
removed.</para>
<para>Image verification is identical for raw and tar images
(see above).</para>
<para>If the downloaded image is in
<filename>.qcow2</filename> format it is converted into a raw
image file before it is made available.</para>
<para>Downloaded images of this type will be placed as
read-only <filename>.raw</filename> file in
<filename>/var/lib/machines/</filename>. A local, writable
(reflinked) copy is then made under the specified local
machine name. To omit creation of the local, writable copy
pass <literal>-</literal> as local machine name.</para>
<para>Similar to the behavior of <command>pull-tar</command>,
the read-only image is prefixed with
<filename>.raw-</filename>, and thus not shown by
<command>list-images</command>, unless <option>--all</option>
is passed.</para>
<para>Note that pressing C-c during execution of this command
will not abort the download. Use
<command>cancel-transfer</command>, described
below.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>import-tar</command> <replaceable>FILE</replaceable> [<replaceable>NAME</replaceable>]</term>
<term><command>import-raw</command> <replaceable>FILE</replaceable> [<replaceable>NAME</replaceable>]</term>
<listitem><para>Imports a TAR or RAW container or VM image,
and places it under the specified name in
<filename>/var/lib/machines/</filename>. When
<command>import-tar</command> is used, the file specified as
the first argument should be a tar archive, possibly compressed
with xz, gzip or bzip2. It will then be unpacked into its own
subvolume in <filename>/var/lib/machines</filename>. When
<command>import-raw</command> is used, the file should be a
qcow2 or raw disk image, possibly compressed with xz, gzip or
bzip2. If the second argument (the resulting image name) is
not specified, it is automatically derived from the file
name. If the file name is passed as <literal>-</literal>, the
image is read from standard input, in which case the second
argument is mandatory.</para>
<para>Both <command>pull-tar</command> and <command>pull-raw</command>
will resize <filename>/var/lib/machines.raw</filename> and the
filesystem therein as necessary. Optionally, the
<option>--read-only</option> switch may be used to create a
read-only container or VM image. No cryptographic validation
is done when importing the images.</para>
<para>Much like image downloads, ongoing imports may be listed
with <command>list-transfers</command> and aborted with
<command>cancel-transfer</command>.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>export-tar</command> <replaceable>NAME</replaceable> [<replaceable>FILE</replaceable>]</term>
<term><command>export-raw</command> <replaceable>NAME</replaceable> [<replaceable>FILE</replaceable>]</term>
<listitem><para>Exports a TAR or RAW container or VM image and
stores it in the specified file. The first parameter should be
a VM or container image name. The second parameter should be a
file path the TAR or RAW image is written to. If the path ends
in <literal>.gz</literal>, the file is compressed with gzip, if
it ends in <literal>.xz</literal>, with xz, and if it ends in
<literal>.bz2</literal>, with bzip2. If the path ends in
neither, the file is left uncompressed. If the second argument
is missing, the image is written to standard output. The
compression may also be explicitly selected with the
<option>--format=</option> switch. This is in particular
useful if the second parameter is left unspecified.</para>
<para>Much like image downloads and imports, ongoing exports
may be listed with <command>list-transfers</command> and
aborted with
<command>cancel-transfer</command>.</para>
<para>Note that, currently, only directory and subvolume images
may be exported as TAR images, and only raw disk images as RAW
images.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>list-transfers</command></term>
<listitem><para>Shows a list of container or VM image
downloads, imports and exports that are currently in
progress.</para></listitem>
</varlistentry>
<varlistentry>
<term><command>cancel-transfers</command> <replaceable>ID</replaceable>...</term>
<listitem><para>Aborts a download, import or export of the
container or VM image with the specified ID. To list ongoing
transfers and their IDs, use
<command>list-transfers</command>. </para></listitem>
</varlistentry>
</variablelist></refsect2>
</refsect1>
<refsect1>
<title>Machine and Image Names</title>
<para>The <command>machinectl</command> tool operates on machines
and images whose names must be chosen following strict
rules. Machine names must be suitable for use as host names
following a conservative subset of DNS and UNIX/Linux
semantics. Specifically, they must consist of one or more
non-empty label strings, separated by dots. No leading or trailing
dots are allowed. No sequences of multiple dots are allowed. The
label strings may only consist of alphanumeric characters as well
as the dash and underscore. The maximum length of a machine name
is 64 characters.</para>
<para>A special machine with the name <literal>.host</literal>
refers to the running host system itself. This is useful for execution
operations or inspecting the host system as well. Note that
<command>machinectl list</command> will not show this special
machine unless the <option>--all</option> switch is specified.</para>
<para>Requirements on image names are less strict, however, they must be
valid UTF-8, must be suitable as file names (hence not be the
single or double dot, and not include a slash), and may not
contain control characters. Since many operations search for an
image by the name of a requested machine, it is recommended to name
images in the same strict fashion as machines.</para>
<para>A special image with the name <literal>.host</literal>
refers to the image of the running host system. It hence
conceptually maps to the special <literal>.host</literal> machine
name described above. Note that <command>machinectl
list-images</command> will not show this special image either, unless
<option>--all</option> is specified.</para>
</refsect1>
<refsect1>
<title>Files and Directories</title>
<para>Machine images are preferably stored in
<filename>/var/lib/machines/</filename>, but are also searched for
in <filename>/usr/local/lib/machines/</filename> and
<filename>/usr/lib/machines/</filename>. For compatibility reasons,
the directory <filename>/var/lib/container/</filename> is
searched, too. Note that images stored below
<filename>/usr</filename> are always considered read-only. It is
possible to symlink machines images from other directories into
<filename>/var/lib/machines/</filename> to make them available for
control with <command>machinectl</command>.</para>
<para>Note that many image operations are only supported,
efficient or atomic on btrfs file systems. Due to this, if the
<command>pull-tar</command>, <command>pull-raw</command>,
<command>import-tar</command>, <command>import-raw</command> and
<command>set-limit</command> commands notice that
<filename>/var/lib/machines</filename> is empty and not located on
btrfs, they will implicitly set up a loopback file
<filename>/var/lib/machines.raw</filename> containing a btrfs file
system that is mounted to
<filename>/var/lib/machines</filename>. The size of this loopback
file may be controlled dynamically with
<command>set-limit</command>.</para>
<para>Disk images are understood by
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
and <command>machinectl</command> in three formats:</para>
<itemizedlist>
<listitem><para>A simple directory tree, containing the files
and directories of the container to boot.</para></listitem>
<listitem><para>Subvolumes (on btrfs file systems), which are
similar to the simple directories, described above. However,
they have additional benefits, such as efficient cloning and
quota reporting.</para></listitem>
<listitem><para>"Raw" disk images, i.e. binary images of disks
with a GPT or MBR partition table. Images of this type are
regular files with the suffix
<literal>.raw</literal>.</para></listitem>
</itemizedlist>
<para>See
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
for more information on image formats, in particular its
<option>--directory=</option> and <option>--image=</option>
options.</para>
</refsect1>
<refsect1>
<title>Examples</title>
<example>
<title>Download an Ubuntu image and open a shell in it</title>
<programlisting># machinectl pull-tar https://cloud-images.ubuntu.com/trusty/current/trusty-server-cloudimg-amd64-root.tar.gz
# systemd-nspawn -M trusty-server-cloudimg-amd64-root</programlisting>
<para>This downloads and verifies the specified
<filename>.tar</filename> image, and then uses
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>
to open a shell in it.</para>
</example>
<example>
<title>Download a Fedora image, set a root password in it, start
it as service</title>
<programlisting># machinectl pull-raw --verify=no https://dl.fedoraproject.org/pub/fedora/linux/releases/23/Cloud/x86_64/Images/Fedora-Cloud-Base-23-20151030.x86_64.raw.xz
# systemd-nspawn -M Fedora-Cloud-Base-23-20151030
# passwd
# exit
# machinectl start Fedora-Cloud-Base-23-20151030
# machinectl login Fedora-Cloud-Base-23-20151030</programlisting>
<para>This downloads the specified <filename>.raw</filename>
image with verification disabled. Then, a shell is opened in it
and a root password is set. Afterwards the shell is left, and
the machine started as system service. With the last command a
login prompt into the container is requested.</para>
</example>
<example>
<title>Exports a container image as tar file</title>
<programlisting># machinectl export-tar fedora myfedora.tar.xz</programlisting>
<para>Exports the container <literal>fedora</literal> as an
xz-compressed tar file <filename>myfedora.tar.xz</filename> into the
current directory.</para>
</example>
<example>
<title>Create a new shell session</title>
<programlisting># machinectl shell --uid=lennart</programlisting>
<para>This creates a new shell session on the local host for
the user ID <literal>lennart</literal>, in a <citerefentry
project='die-net'><refentrytitle>su</refentrytitle><manvolnum>1</manvolnum></citerefentry>-like
fashion.</para>
</example>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, a non-zero failure code
otherwise.</para>
</refsect1>
<xi:include href="less-variables.xml" />
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>tar</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>xz</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>gzip</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='die-net'><refentrytitle>bzip2</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
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