importctl(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | EXAMPLES | EXIT STATUS | ENVIRONMENT | SEE ALSO | COLOPHON

IMPORTCTL(1)                    importctl                   IMPORTCTL(1)

NAME         top

       importctl - Download, import or export disk images

SYNOPSIS         top


       importctl [OPTIONS...] {COMMAND} [NAME...]

DESCRIPTION         top

       importctl may be used to download, import, and export disk images
       via systemd-importd.service(8).

       importctl operates both on block-level disk images (such as DDIs)
       as well as file-system-level images (tarballs). It supports disk
       images are one of the four following classes:

       •   VM images or full OS container images, that may be run via
           systemd-vmspawn(1) or systemd-nspawn(1), and managed via
           machinectl(1).

       •   Portable service images, that may be attached an managed via
           portablectl(1).

       •   System extension (sysext) images, that may be activated via
           systemd-sysext(8).

       •   Configuration extension (confext) images, that may be
           activated via systemd-confext(8).

       When images are downloaded or imported they are placed in the
       following directories, depending on the --class= parameter:

       Table 1. Classes and Directories
       ┌────────────┬──────────────────────┐
       │ Class      Directory            │
       ├────────────┼──────────────────────┤
       │ "machine"  │ /var/lib/machines/   │
       ├────────────┼──────────────────────┤
       │ "portable" │ /var/lib/portables/  │
       ├────────────┼──────────────────────┤
       │ "sysext"   │ /var/lib/extensions/ │
       ├────────────┼──────────────────────┤
       │ "confext"  │ /var/lib/confexts/   │
       └────────────┴──────────────────────┘

COMMANDS         top

       The following commands are understood:

       pull-tar URL [NAME]
           Downloads a .tar image from the specified URL, and makes it
           available under the specified local name in the image
           directory for the selected --class=. The URL must be of type
           "http://" or "https://", and must refer to a .tar, .tar.gz,
           .tar.xz or .tar.bz2 archive file. If the local image name is
           omitted, it is automatically derived from the last component
           of the URL, with its suffix removed.

           The image is verified before it is made available, unless
           --verify=no is specified. Verification is done either via an
           inline signed file with the name of the image and the suffix
           .sha256 or via separate SHA256SUMS and SHA256SUMS.gpg files.
           The signature files need to be made available on the same web
           server, under the same URL as the .tar file. With
           --verify=checksum, only the SHA256 checksum for the file is
           verified, based on the .sha256 suffixed file or the
           SHA256SUMS file. With --verify=signature, the sha checksum
           file is first verified with the inline signature in the
           .sha256 file or the detached GPG signature file
           SHA256SUMS.gpg. The public key for this verification step
           needs to be available in /usr/lib/systemd/import-pubring.gpg
           or /etc/systemd/import-pubring.gpg.

           If -keep-download=yes is specified the image will be
           downloaded and stored in a read-only subvolume/directory in
           the image directory 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 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 "-" as local name.

           Note that pressing C-c during execution of this command will
           not abort the download. Use cancel-transfer, described below.

           Added in version 256.

       pull-raw URL [NAME]
           Downloads a .raw disk image from the specified URL, and makes
           it available under the specified local name in the image
           directory for the selected --class=. The URL must be of type
           "http://" or "https://". The image must either be a .qcow2 or
           raw disk image, optionally compressed as .gz, .xz, or .bz2.
           If the local name is omitted, it is automatically derived
           from the last component of the URL, with its suffix removed.

           Image verification is identical for raw and tar images (see
           above).

           If the downloaded image is in .qcow2 format it is converted
           into a raw image file before it is made available.

           If -keep-download=yes is specified the image will be
           downloaded and stored in a read-only file in the image
           directory that is named after the specified URL and its HTTP
           etag. A writable copy is then made from this file, and named
           after the specified local name. This behavior ensures that
           creating multiple 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 copy,
           specify "-" as local name.

           Note that pressing C-c during execution of this command will
           not abort the download. Use cancel-transfer, described below.

           Added in version 256.

       import-tar FILE [NAME], import-raw FILE [NAME]
           Imports a TAR or RAW image, and places it under the specified
           name in the image directory for the image class selected via
           --class=. When import-tar 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/directory. When import-raw 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 filename is passed as "-", the image is
           read from standard input, in which case the second argument
           is mandatory.

           No cryptographic validation is done when importing the
           images.

           Much like image downloads, ongoing imports may be listed with
           list and aborted with cancel-transfer.

           Added in version 256.

       import-fs DIRECTORY [NAME]
           Imports an image stored in a local directory into the image
           directory for the image class selected via --class= and
           operates similarly to import-tar or import-raw, but the first
           argument is the source directory. If supported, this command
           will create a btrfs snapshot or subvolume for the new image.

           Added in version 256.

       export-tar NAME [FILE], export-raw NAME [FILE]
           Exports a TAR or RAW image and stores it in the specified
           file. The first parameter should be an image name. The second
           parameter should be a file path the TAR or RAW image is
           written to. If the path ends in ".gz", the file is compressed
           with gzip, if it ends in ".xz", with xz, and if it ends in
           ".bz2", 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 --format= switch. This is in
           particular useful if the second parameter is left
           unspecified.

           Much like image downloads and imports, ongoing exports may be
           listed with list and aborted with cancel-transfer.

           Note that, currently, only directory and subvolume images may
           be exported as TAR images, and only raw disk images as RAW
           images.

           Added in version 256.

       list-transfer
           Shows a list of image downloads, imports and exports that are
           currently in progress.

           Added in version 256.

       cancel-transfer ID...
           Aborts a download, import or export of the image with the
           specified ID. To list ongoing transfers and their IDs, use
           list.

           Added in version 256.

       list-images
           Shows a list of already downloaded/imported images.

           Added in version 256.

OPTIONS         top

       The following options are understood:

       --read-only
           When used with pull-raw, pull-tar, import-raw, import-tar or
           import-fs a read-only image is created.

           Added in version 256.

       --verify=
           When downloading an image, specify whether the image shall be
           verified before it is made available. Takes one of "no",
           "checksum" and "signature". If "no", no verification is done.
           If "checksum" is specified, the download is checked for
           integrity after the transfer is complete, but no signatures
           are verified. If "signature" 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 "signature" if the server and protocol
           support this. Defaults to "signature".

           Added in version 256.

       --force
           When downloading an image, and a local copy by the specified
           local name already exists, delete it first and replace it by
           the newly downloaded image.

           Added in version 256.

       --format=
           When used with the export-tar or export-raw commands,
           specifies the compression format to use for the resulting
           file. Takes one of "uncompressed", "xz", "gzip", "bzip2". By
           default, the format is determined automatically from the
           output image file name passed.

           Added in version 256.

       -q, --quiet
           Suppresses additional informational output while running.

           Added in version 256.

       -H, --host=
           Execute the operation remotely. Specify a hostname, or a
           username and hostname separated by "@", to connect to. The
           hostname may optionally be suffixed by a port ssh is
           listening on, separated by ":", and then a container name,
           separated by "/", which connects directly to a specific
           container on the specified host. This will use SSH to talk to
           the remote machine manager instance. Container names may be
           enumerated with machinectl -H HOST. Put IPv6 addresses in
           brackets.

       -M, --machine=
           Connect to systemd-import.service(8) running in a local
           container, to perform the specified operation within the
           container.

           Added in version 256.

       --class=, -m, -P, -S, -C
           Selects the image class for the downloaded images. This
           primarily selects the directory to download into. The
           --class= switch takes "machine", "portable", "sysext" or
           "confext" as argument. The short options -m, -P, -S, -C are
           shortcuts for --class=machine, --class=portable,
           --class=sysext, --class=confext.

           Note that --keep-download= defaults to true for
           --class=machine and false otherwise, see below.

           Added in version 256.

       --keep-download=, -N
           Takes a boolean argument. When specified with pull-raw or
           pull-tar, selects whether to download directly into the
           specified local image name, or whether to download into a
           read-only copy first of which to make a writable copy after
           the download is completed. Defaults to true for
           --class=machine, false otherwise.

           The -N switch is a shortcut for --keep-download=no.

           Added in version 256.

       --json=MODE
           Shows output formatted as JSON. Expects one of "short" (for
           the shortest possible output without any redundant whitespace
           or line breaks), "pretty" (for a pretty version of the same,
           with indentation and line breaks) or "off" (to turn off JSON
           output, the default).

       -j
           Equivalent to --json=pretty if running on a terminal, and
           --json=short otherwise.

       --no-pager
           Do not pipe output into a pager.

       --no-legend
           Do not print the legend, i.e. column headers and the footer
           with hints.

       --no-ask-password
           Do not query the user for authentication for privileged
           operations.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

EXAMPLES         top

       Example 1. Download an Ubuntu TAR image and open a shell in it

           # importctl pull-tar -mN https://cloud-images.ubuntu.com/jammy/current/jammy-server-cloudimg-amd64-root.tar.xz
           # systemd-nspawn -M jammy-server-cloudimg-amd64-root

       This downloads and verifies the specified .tar image, and then
       uses systemd-nspawn(1) to open a shell in it.

       Example 2. Download an Ubuntu RAW image, set a root password in
       it, start it as a service

           # importctl pull-raw -mN \
                 https://cloud-images.ubuntu.com/jammy/current/jammy-server-cloudimg-amd64-disk-kvm.img \
                 jammy
           # systemd-firstboot --image=/var/lib/machines/jammy.raw --prompt-root-password --force
           # machinectl start jammy
           # machinectl login jammy

       This downloads the specified .raw image and makes it available
       under the local name "jammy". Then, a root password is set with
       systemd-firstboot(1). Afterwards the machine is started as system
       service. With the last command a login prompt into the container
       is requested.

       Example 3. Exports a container image as tar file

           # importctl export-tar -m fedora myfedora.tar.xz

       Exports the container "fedora" as an xz-compressed tar file
       myfedora.tar.xz into the current directory.

EXIT STATUS         top

       On success, 0 is returned, a non-zero failure code otherwise.

ENVIRONMENT         top

       $SYSTEMD_LOG_LEVEL
           The maximum log level of emitted messages (messages with a
           higher log level, i.e. less important ones, will be
           suppressed). Takes a comma-separated list of values. A value
           may be either one of (in order of decreasing importance)
           emerg, alert, crit, err, warning, notice, info, debug, or an
           integer in the range 0...7. See syslog(3) for more
           information. Each value may optionally be prefixed with one
           of console, syslog, kmsg or journal followed by a colon to
           set the maximum log level for that specific log target (e.g.
           SYSTEMD_LOG_LEVEL=debug,console:info specifies to log at
           debug level except when logging to the console which should
           be at info level). Note that the global maximum log level
           takes priority over any per target maximum log levels.

       $SYSTEMD_LOG_COLOR
           A boolean. If true, messages written to the tty will be
           colored according to priority.

           This setting is only useful when messages are written
           directly to the terminal, because journalctl(1) and other
           tools that display logs will color messages based on the log
           level on their own.

       $SYSTEMD_LOG_TIME
           A boolean. If true, console log messages will be prefixed
           with a timestamp.

           This setting is only useful when messages are written
           directly to the terminal or a file, because journalctl(1) and
           other tools that display logs will attach timestamps based on
           the entry metadata on their own.

       $SYSTEMD_LOG_LOCATION
           A boolean. If true, messages will be prefixed with a filename
           and line number in the source code where the message
           originates.

           Note that the log location is often attached as metadata to
           journal entries anyway. Including it directly in the message
           text can nevertheless be convenient when debugging programs.

       $SYSTEMD_LOG_TID
           A boolean. If true, messages will be prefixed with the
           current numerical thread ID (TID).

           Note that the this information is attached as metadata to
           journal entries anyway. Including it directly in the message
           text can nevertheless be convenient when debugging programs.

       $SYSTEMD_LOG_TARGET
           The destination for log messages. One of console (log to the
           attached tty), console-prefixed (log to the attached tty but
           with prefixes encoding the log level and "facility", see
           syslog(3), kmsg (log to the kernel circular log buffer),
           journal (log to the journal), journal-or-kmsg (log to the
           journal if available, and to kmsg otherwise), auto (determine
           the appropriate log target automatically, the default), null
           (disable log output).

       $SYSTEMD_LOG_RATELIMIT_KMSG
           Whether to ratelimit kmsg or not. Takes a boolean. Defaults
           to "true". If disabled, systemd will not ratelimit messages
           written to kmsg.

       $SYSTEMD_PAGER
           Pager to use when --no-pager is not given; overrides $PAGER.
           If neither $SYSTEMD_PAGER nor $PAGER are set, a set of
           well-known pager implementations are tried in turn, including
           less(1) and more(1), until one is found. If no pager
           implementation is discovered no pager is invoked. Setting
           this environment variable to an empty string or the value
           "cat" is equivalent to passing --no-pager.

           Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER (as
           well as $PAGER) will be silently ignored.

       $SYSTEMD_LESS
           Override the options passed to less (by default "FRSXMK").

           Users might want to change two options in particular:

           K
               This option instructs the pager to exit immediately when
               Ctrl+C is pressed. To allow less to handle Ctrl+C itself
               to switch back to the pager command prompt, unset this
               option.

               If the value of $SYSTEMD_LESS does not include "K", and
               the pager that is invoked is less, Ctrl+C will be ignored
               by the executable, and needs to be handled by the pager.

           X
               This option instructs the pager to not send termcap
               initialization and deinitialization strings to the
               terminal. It is set by default to allow command output to
               remain visible in the terminal even after the pager
               exits. Nevertheless, this prevents some pager
               functionality from working, in particular paged output
               cannot be scrolled with the mouse.

           Note that setting the regular $LESS environment variable has
           no effect for less invocations by systemd tools.

           See less(1) for more discussion.

       $SYSTEMD_LESSCHARSET
           Override the charset passed to less (by default "utf-8", if
           the invoking terminal is determined to be UTF-8 compatible).

           Note that setting the regular $LESSCHARSET environment
           variable has no effect for less invocations by systemd tools.

       $SYSTEMD_PAGERSECURE
           Takes a boolean argument. When true, the "secure" mode of the
           pager is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE
           is not set at all, secure mode is enabled if the effective
           UID is not the same as the owner of the login session, see
           geteuid(2) and sd_pid_get_owner_uid(3). In secure mode,
           LESSSECURE=1 will be set when invoking the pager, and the
           pager shall disable commands that open or create new files or
           start new subprocesses. When $SYSTEMD_PAGERSECURE is not set
           at all, pagers which are not known to implement secure mode
           will not be used. (Currently only less(1) implements secure
           mode.)

           Note: when commands are invoked with elevated privileges, for
           example under sudo(8) or pkexec(1), care must be taken to
           ensure that unintended interactive features are not enabled.
           "Secure" mode for the pager may be enabled automatically as
           describe above. Setting SYSTEMD_PAGERSECURE=0 or not removing
           it from the inherited environment allows the user to invoke
           arbitrary commands. Note that if the $SYSTEMD_PAGER or $PAGER
           variables are to be honoured, $SYSTEMD_PAGERSECURE must be
           set too. It might be reasonable to completely disable the
           pager using --no-pager instead.

       $SYSTEMD_COLORS
           Takes a boolean argument. When true, systemd and related
           utilities will use colors in their output, otherwise the
           output will be monochrome. Additionally, the variable can
           take one of the following special values: "16", "256" to
           restrict the use of colors to the base 16 or 256 ANSI colors,
           respectively. This can be specified to override the automatic
           decision based on $TERM and what the console is connected to.

       $SYSTEMD_URLIFY
           The value must be a boolean. Controls whether clickable links
           should be generated in the output for terminal emulators
           supporting this. This can be specified to override the
           decision that systemd makes based on $TERM and other
           conditions.

SEE ALSO         top

       systemd(1), systemd-importd.service(8), systemd-nspawn(1),
       systemd-vmspawn(1), machinectl(1), portablectl(1),
       systemd-sysext(8), systemd-confext(8), tar(1), xz(1), gzip(1),
       bzip2(1)

COLOPHON         top

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systemd 257~devel                                           IMPORTCTL(1)

Pages that refer to this page: machinectl(1)portablectl(1)systemd-nspawn(1)systemd-vmspawn(1)systemd.directives(7)systemd.index(7)systemd-importd.service(8)systemd-sysext(8)