|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|
|
NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | EXAMPLES | EXIT STATUS | ENVIRONMENT | SEE ALSO | COLOPHON |
|
|
|
IMPORTCTL(1) importctl IMPORTCTL(1)
importctl - Download, import or export disk images
importctl [OPTIONS...] {COMMAND} [NAME...]
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/ │
└────────────┴──────────────────────┘
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.
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.
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.
On success, 0 is returned, a non-zero failure code otherwise.
$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.
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)
This page is part of the systemd (systemd system and service
manager) project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have
a bug report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
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)
|
HTML rendering created 2024-06-26 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|