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Diffstat (limited to 'man/machinectl.xml')
| -rw-r--r-- | man/machinectl.xml | 447 |
1 files changed, 291 insertions, 156 deletions
diff --git a/man/machinectl.xml b/man/machinectl.xml index 4b87870853..eaa247714b 100644 --- a/man/machinectl.xml +++ b/man/machinectl.xml @@ -1,4 +1,4 @@ -<?xml version='1.0'?> <!--*-nxml-*--> +<?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"> @@ -65,6 +65,43 @@ <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> @@ -96,7 +133,16 @@ <para>When listing VM or container images, do not suppress images beginning in a dot character - (<literal>.</literal>).</para></listitem> + (<literal>.</literal>).</para> + + <para>When cleaning VM or container images, remove all images, not just hidden ones.</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> @@ -138,21 +184,43 @@ </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 the argument to the <command>shell</command> + command also specifies an user name, this option is ignored. If the name is not specified + in either way, <literal>root</literal> will be used by default. Note that this switch is + not supported for the <command>login</command> command (see below).</para></listitem> + </varlistentry> + + <varlistentry> + <term><option>-E <replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term> + <term><option>--setenv=<replaceable>NAME</replaceable>=<replaceable>VALUE</replaceable></option></term> + + <listitem><para>When used with the <command>shell</command> command, sets an environment + variable to pass to the executed shell. Takes an environment variable name and value, + separated by <literal>=</literal>. 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 + <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> + <listitem><para>When used with <command>bind</command>, applies + a read-only bind mount.</para> + <para>When used with <command>clone</command>, <command>import-raw</command> or <command>import-tar</command> a + read-only container or VM image is created.</para></listitem> + </varlistentry> <varlistentry> <term><option>-n</option></term> @@ -183,11 +251,11 @@ 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 transfer is complete, but no + 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 images's signature + 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 @@ -205,27 +273,31 @@ </varlistentry> <varlistentry> - <term><option>--dkr-index-url</option></term> - - <listitem><para>Specifies the index server to use for - downloading <literal>dkr</literal> images with the - <command>pull-dkr</command>. Takes a - <literal>http://</literal>, <literal>https://</literal> - URL.</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 + 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 + <literal>gzip</literal>, <literal>bzip2</literal>. By default, the format is determined automatically from the image file name passed.</para></listitem> </varlistentry> + <varlistentry> + <term><option>--max-addresses=</option></term> + + <listitem><para>When used with the <option>list-machines</option> + command, limits the number of ip addresses output for every machine. + Defaults to 1. All addresses can be requested with <literal>all</literal> + as argument to <option>--max-addresses</option> . If the argument to + <option>--max-addresses</option> is less than the actual number + of addresses,<literal>...</literal>follows the last address. + If multiple addresses are to be written for a given machine, every + address except the first one is on a new line and is followed by + <literal>,</literal> if another address will be output afterwards. </para></listitem> + </varlistentry> + <xi:include href="user-system-options.xml" xpointer="host" /> <xi:include href="user-system-options.xml" xpointer="machine" /> @@ -247,15 +319,17 @@ <term><command>list</command></term> <listitem><para>List currently running (online) virtual - machines and containers. To enumerate container images that - can be started, use <command>list-images</command> (see - below).</para></listitem> + 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 terse runtime status information about + <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 @@ -267,17 +341,18 @@ </varlistentry> <varlistentry> - <term><command>show</command> <replaceable>NAME</replaceable>...</term> + <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 + shown. If a 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. Use + 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> @@ -294,7 +369,7 @@ 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 + <command>list-images</command> (see below) for listing available container images to start.</para> <para>Note that @@ -311,26 +386,71 @@ <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> + container use <command>machinectl poweroff</command>.</para></listitem> </varlistentry> <varlistentry> - <term><command>login</command> <replaceable>NAME</replaceable></term> - - <listitem><para>Open an interactive terminal login session to - a container. This will create a TTY connection to a specific - container and asks for the execution of a getty on it. Note - that this is only supported for containers running + <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, which then asks for username and password. Use + 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 invoke a single - command, either interactively or in the background within a - local container.</para></listitem> + 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> @@ -353,8 +473,8 @@ <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 + down cleanly. Use <command>stop</command> as alias for <command>poweroff</command>. + 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 @@ -401,11 +521,11 @@ 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 + 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 + 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 + <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> @@ -418,7 +538,7 @@ <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 + path in the container. If the destination path is omitted, the same as the source path is used.</para></listitem> </varlistentry> @@ -429,7 +549,7 @@ <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 + If the destination path is omitted, the same as the source path is used.</para></listitem> </varlistentry> </variablelist></refsect2> @@ -444,8 +564,8 @@ 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 + 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 @@ -453,7 +573,7 @@ </varlistentry> <varlistentry> - <term><command>image-status</command> <replaceable>NAME</replaceable>...</term> + <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 @@ -463,12 +583,12 @@ </varlistentry> <varlistentry> - <term><command>show-image</command> <replaceable>NAME</replaceable>...</term> + <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 + shown. If a 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 @@ -481,19 +601,20 @@ <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> + <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 btrfs subvolume + images with this command, if the underlying file system supports this. 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> + change them in the copy.</para> + + <para>If combined with the <option>--read-only</option> switch a read-only cloned image is + created.</para></listitem> </varlistentry> <varlistentry> @@ -518,27 +639,27 @@ <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 + 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 a specific - container or VM image, or all images may grow up to on disk + <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 + 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 image + 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 @@ -548,12 +669,29 @@ 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 image + 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> + <varlistentry> + <term><command>clean</command></term> + + <listitem><para>Remove hidden VM or container images (or all). This command removes all hidden machine images + from <filename>/var/lib/machines</filename>, i.e. those whose name begins with a dot. Use <command>machinectl + list-images --all</command> to see a list of all machine images, including the hidden ones.</para> + + <para>When combined with the <option>--all</option> switch removes all images, not just hidden ones. This + command effectively empties <filename>/var/lib/machines</filename>.</para> + + <para>Note that commands such as <command>machinectl pull-tar</command> or <command>machinectl + pull-raw</command> usually create hidden, read-only, unmodified machine images from the downloaded image first, + before cloning a writable working copy of it, in order to avoid duplicate downloads in case of images that are + reused multiple times. Use <command>machinectl clean</command> to remove old, hidden images created this + way.</para></listitem> + </varlistentry> + </variablelist></refsect2> <refsect2><title>Image Transfer Commands</title><variablelist> @@ -568,20 +706,20 @@ <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 + 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 + 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 + <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 + <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 @@ -590,10 +728,10 @@ <para>The container image will be downloaded and stored in a read-only subvolume in - <filename>/var/lib/machines/</filename>, that is named after + <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 behaviour ensures that creating multiple + 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, @@ -621,7 +759,7 @@ 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 + local machine name is omitted, it is automatically derived from the last component of the URL, with its suffix removed.</para> @@ -639,7 +777,7 @@ machine name. To omit creation of the local, writable copy pass <literal>-</literal> as local machine name.</para> - <para>Similar to the behaviour of <command>pull-tar</command>, + <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> @@ -652,63 +790,26 @@ </varlistentry> <varlistentry> - <term><command>pull-dkr</command> <replaceable>REMOTE</replaceable> [<replaceable>NAME</replaceable>]</term> - - <listitem><para>Downloads a <literal>dkr</literal> container - image and makes it available locally. The remote name refers - to a <literal>dkr</literal> container name. If omitted, the - local machine name is derived from the <literal>dkr</literal> - container name.</para> - - <para>Image verification is not available for - <literal>dkr</literal> containers, and thus - <option>--verify=no</option> must always be specified with - this command.</para> - - <para>This command downloads all (missing) layers for the - specified container and places them in read-only subvolumes in - <filename>/var/lib/machines/</filename>. A writable snapshot - of the newest layer is then created under the specified local - machine name. To omit creation of this writable snapshot, pass - <literal>-</literal> as local machine name.</para> - - <para>The read-only layer subvolumes are prefixed with - <filename>.dkr-</filename>, and thus not shown by - <command>list-images</command>, unless <option>--all</option> - is passed.</para> - - <para>To specify the <literal>dkr</literal> index server to - use for looking up the specified container, use - <option>--dkr-index-url=</option>.</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 - first argument should be a tar archive, possibly compressed + <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 + <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 + 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>Similar as with <command>pull-tar</command>, - <command>pull-raw</command> the file system - <filename>/var/lib/machines.raw</filename> is increased in - size of necessary and appropriate. Optionally the + <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> @@ -725,11 +826,11 @@ 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 + 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> @@ -739,7 +840,7 @@ aborted with <command>cancel-transfer</command>.</para> - <para>Note that currently only directory and subvolume images + <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> @@ -766,12 +867,47 @@ </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 + <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 @@ -782,12 +918,12 @@ <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>pull-dkr</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 + <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> @@ -800,7 +936,7 @@ <listitem><para>A simple directory tree, containing the files and directories of the container to boot.</para></listitem> - <listitem><para>A subvolume (on btrfs file systems), which are + <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> @@ -813,7 +949,7 @@ <para>See <citerefentry><refentrytitle>systemd-nspawn</refentrytitle><manvolnum>1</manvolnum></citerefentry> - for more information on image formats, in particular it's + for more information on image formats, in particular its <option>--directory=</option> and <option>--image=</option> options.</para> </refsect1> @@ -836,40 +972,39 @@ <title>Download a Fedora image, set a root password in it, start it as service</title> - <programlisting># machinectl pull-raw --verify=no http://ftp.halifax.rwth-aachen.de/fedora/linux/releases/21/Cloud/Images/x86_64/Fedora-Cloud-Base-20141203-21.x86_64.raw.xz -# systemd-nspawn -M Fedora-Cloud-Base-20141203-21 + <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-20141203-21 -# machinectl login Fedora-Cloud-Base-20141203-21</programlisting> +# 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 + 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>Download a Fedora <literal>dkr</literal> image</title> + <title>Exports a container image as tar file</title> - <programlisting># machinectl pull-dkr --verify=no mattdm/fedora -# systemd-nspawn -M fedora</programlisting> + <programlisting># machinectl export-tar fedora myfedora.tar.xz</programlisting> - <para>Downloads a <literal>dkr</literal> image and opens a shell - in it. Note that the specified download command might require an - index server to be specified with the - <literal>--dkr-index-url=</literal>.</para> + <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>Exports a container image as tar file</title> + <title>Create a new shell session</title> - <programlisting># machinectl export-tar fedora myfedora.tar.xz</programlisting> + <programlisting># machinectl shell --uid=lennart</programlisting> - <para>Exports the container <literal>fedora</literal> in an - xz-compress tar file <filename>myfedora.tar.xz</filename> in the - current directory.</para> + <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> |