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NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | FILES AND DIRECTORIES | PROFILES | EXIT STATUS | ENVIRONMENT | SEE ALSO | NOTES | COLOPHON |
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PORTABLECTL(1) portablectl PORTABLECTL(1)
portablectl - Attach, detach or inspect portable service images
portablectl [OPTIONS...] {COMMAND} [NAME...]
portablectl may be used to attach, detach or inspect portable
service images. It's primarily a command interfacing with
systemd-portabled.service(8).
Portable service images contain an OS file system tree along with
systemd(1) unit file information. A service image may be
"attached" to the local system. If attached, a set of unit files
are copied from the image to the host, and extended with
RootDirectory= or RootImage= assignments (in case of service
units) pointing to the image file or directory, ensuring the
services will run within the file system context of the image.
Portable service images are an efficient way to bundle multiple
related services and other units together, and transfer them as a
whole between systems. When these images are attached to the local
system, the contained units may run in most ways like regular
system-provided units, either with full privileges or inside
strict sandboxing, depending on the selected configuration. For
more details, see Portable Services[1].
Portable service images may be of the following kinds:
• Directory trees containing an OS, including the top-level
directories /usr/, /etc/, and so on.
• btrfs subvolumes containing OS trees, similar to normal
directory trees.
• Binary "raw" disk images containing MBR or GPT partition
tables and Linux file system partitions. (These must be
regular files, with the .raw suffix.)
The following commands are understood:
list
List available portable service images. This will list all
portable service images discovered in the portable image
search paths (see below), along with brief metadata and state
information. Note that many of the commands below may both
operate on images inside and outside of the search paths. This
command is hence mostly a convenience option, the commands are
generally not restricted to what this list shows.
Added in version 239.
attach IMAGE [PREFIX...]
Attach a portable service image to the host system. Expects a
file system path to a portable service image file or directory
as first argument. If the specified path contains no slash
character ("/") it is understood as image filename that is
searched for in the portable service image search paths (see
below). To reference a file in the current working directory
prefix the filename with "./" to avoid this search path logic.
When a portable service is attached four operations are
executed:
1. All unit files of types .service, .socket, .target, .timer
and .path which match the indicated unit file name prefix
are copied from the image to the host's
/etc/systemd/system.attached/ directory (or
/run/systemd/system.attached/ — depending whether
--runtime is specified, see below), which is included in
the built-in unit search path of the system service
manager.
2. For unit files of type .service a drop-in is added to
these copies that adds RootDirectory= or RootImage=
settings (see systemd.unit(5) for details), that ensures
these services are run within the file system of the
originating portable service image.
3. A second drop-in is created: the "profile" drop-in, that
may contain additional security settings (and other
settings). A number of profiles are available by default
but administrators may define their own ones. See below.
4. If the portable service image file is not already in the
search path (see below), a symbolic link to it is created
in /etc/portables/ or /run/portables/, to make sure it is
included in it.
By default, all unit files whose names start with a prefix
generated from the image's file name are copied out.
Specifically, the prefix is determined from the image file
name with any suffix such as .raw removed, truncated at the
first occurrence of an underscore character ("_"), if there is
one. The underscore logic is supposed to be used to versioning
so that the an image file foobar_47.11.raw will result in a
unit file matching prefix of foobar. This prefix is then
compared with all unit files names contained in the image in
the usual directories, but only unit file names where the
prefix is followed by "-", "." or "@" are considered.
Example: if a portable service image file is named
foobar_47.11.raw then by default all its unit files with names
such as foobar-quux-waldi.service, foobar.service or
[email protected] will be considered. It's possible to override
the matching prefix: all strings listed on the command line
after the image file name are considered prefixes, overriding
the implicit logic where the prefix is derived from the image
file name.
By default, after the unit files are attached the service
manager's configuration is reloaded, except when --no-reload
is specified (see below). This ensures that the new units made
available to the service manager are seen by it.
If --now and/or --enable are passed, the portable services are
immediately started (blocking operation unless --no-block is
passed) and/or enabled after attaching the image.
In place of the image path a ".v/" versioned directory may be
specified, see systemd.v(7) for details.
In place of the directory path a ".v/" versioned directory may
be specified, see systemd.v(7) for details.
Added in version 239.
detach IMAGE [PREFIX...]
Detaches a portable service image from the host. This undoes
the operations executed by the attach command above, and
removes the unit file copies, drop-ins and image symlink
again. This command expects an image name or path as
parameter. Note that if a path is specified only the last
component of it (i.e. the file or directory name itself, not
the path to it) is used for finding matching unit files. This
is a convenience feature to allow all arguments passed as
attach also to detach.
If --now and/or --enable are passed, the portable services are
immediately stopped (blocking operation) and/or disabled
before detaching the image. Prefix(es) are also accepted, to
be used in case the unit names do not match the image name as
described in the attach.
Added in version 239.
reattach IMAGE [PREFIX...]
Detaches an existing portable service image from the host, and
immediately attaches it again. This is useful in case the
image was replaced. Running units are not stopped during the
process. Partial matching, to allow for different versions in
the image name, is allowed: only the part before the first "_"
character has to match. If the new image does not exist, the
existing one will not be detached. The parameters follow the
same syntax as the attach command.
If --now and/or --enable are passed, the portable services are
immediately stopped if removed, started and/or enabled if
added, or restarted if updated. Prefixes are also accepted, in
the same way as described in the attach case.
Added in version 248.
inspect IMAGE [PREFIX...]
Extracts various metadata from a portable service image and
presents it to the caller. Specifically, the os-release(5)
file of the image is retrieved as well as all matching unit
files. By default, a short summary showing the most relevant
metadata in combination with a list of matching unit files is
shown (that is the unit files attach would install to the host
system). If combined with --cat (see above), the os-release
data and the units files' contents is displayed unprocessed.
This command is useful to determine whether an image qualifies
as portable service image, and which unit files are included.
This command expects the path to the image as parameter,
optionally followed by a list of unit file prefixes to
consider, similar to the attach command described above.
Added in version 239.
is-attached IMAGE
Determines whether the specified image is currently attached
or not. Unless combined with the --quiet switch this will show
a short state identifier for the image. Specifically:
Table 1. Image attachment states
┌──────────────────┬──────────────────────────┐
│ State │ Description │
├──────────────────┼──────────────────────────┤
│ detached │ The image is currently │
│ │ not attached. │
├──────────────────┼──────────────────────────┤
│ attached │ The image is currently │
│ │ attached, i.e. its unit │
│ │ files have been made │
│ │ available to the host │
│ │ system. │
├──────────────────┼──────────────────────────┤
│ attached-runtime │ Like attached, but the │
│ │ unit files have been │
│ │ made available │
│ │ transiently only, i.e. │
│ │ the attach command has │
│ │ been invoked with the │
│ │ --runtime option. │
├──────────────────┼──────────────────────────┤
│ enabled │ The image is currently │
│ │ attached, and at least │
│ │ one unit file associated │
│ │ with it has been │
│ │ enabled. │
├──────────────────┼──────────────────────────┤
│ enabled-runtime │ Like enabled, but the │
│ │ unit files have been │
│ │ made available │
│ │ transiently only, i.e. │
│ │ the attach command has │
│ │ been invoked with the │
│ │ --runtime option. │
├──────────────────┼──────────────────────────┤
│ running │ The image is currently │
│ │ attached, and at least │
│ │ one unit file associated │
│ │ with it is running. │
├──────────────────┼──────────────────────────┤
│ running-runtime │ The image is currently │
│ │ attached transiently, │
│ │ and at least one unit │
│ │ file associated with it │
│ │ is running. │
└──────────────────┴──────────────────────────┘
Added in version 239.
read-only IMAGE [BOOL]
Marks or (unmarks) a portable service image read-only. Takes
an image name, followed by a boolean as arguments. If the
boolean is omitted, positive is implied, i.e. the image is
marked read-only.
Added in version 239.
remove IMAGE...
Removes one or more portable service images. Note that this
command will only remove the specified image path itself — it
refers to a symbolic link then the symbolic link is removed
and not the image it points to.
Added in version 239.
set-limit [IMAGE] BYTES
Sets the maximum size in bytes that a specific portable
service 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 portable service 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 "-" as
size.
Note that per-image size limits are only supported on btrfs
file systems. Also, depending on BindPaths= settings in the
portable service's unit files directories from the host might
be visible in the image environment during runtime which are
not affected by this setting, as only the image itself is
counted against this limit.
Added in version 239.
The following options are understood:
-q, --quiet
Suppresses additional informational output while running.
Added in version 239.
-p PROFILE, --profile=PROFILE
When attaching an image, select the profile to use. By
default, the "default" profile is used. For details about
profiles, see below.
Added in version 239.
--copy=
When attaching an image, select whether to prefer copying or
symlinking of files installed into the host system. Takes one
of "copy" (files will be copied), "symlink" (to prefer
creation of symbolic links), "auto" for an intermediary mode
where security profile drop-ins and images are symlinked while
unit files are copied, or "mixed" (since v256) where security
profile drop-ins are symlinked while unit files and images are
copied. Note that this option expresses a preference only, in
cases where symbolic links cannot be created — for example
when the image operated on is a raw disk image, and hence not
directly referentiable from the host file system — copying of
files is used unconditionally.
Added in version 239.
--runtime
When specified the unit and drop-in files are placed in
/run/systemd/system.attached/ instead of
/etc/systemd/system.attached/. Images attached with this
option set hence remain attached only until the next reboot,
while they are normally attached persistently.
Added in version 239.
--no-reload
Do not reload the service manager after attaching or detaching
a portable service image. Normally the service manager is
reloaded to ensure it is aware of added or removed unit files.
Added in version 239.
--cat
When inspecting portable service images, show the
(unprocessed) contents of the metadata files pulled from the
image, instead of brief summaries. Specifically, this will
show the os-release(5) and unit file contents of the image.
Added in version 239.
--enable
Immediately enable/disable the portable service after
attaching/detaching.
Added in version 245.
--now
Immediately start/stop/restart the portable service after
attaching/before detaching/after upgrading.
Added in version 245.
--no-block
Do not block waiting for attach --now to complete.
Added in version 245.
--clean
When detaching ensure the configuration, state, logs, cache,
and runtime data directories of the portable service are
removed from the host system.
Added in version 256.
--extension=PATH
Add an additional image PATH as an overlay on top of IMAGE
when attaching/detaching. This argument can be specified
multiple times, in which case the order in which images are
laid down follows the rules specified in systemd.exec(5) for
the ExtensionImages= directive and for the systemd-sysext(8)
and systemd-confext(8) tools. The images must contain an
extension-release file with metadata that matches what is
defined in the os-release of IMAGE. See: os-release(5). Images
can be block images, btrfs subvolumes or directories. For more
information on portable services with extensions, see the
"Extension Images" paragraph on Portable Services[1].
Note that the same extensions have to be specified, in the
same order, when attaching and detaching.
In place of the image path a ".v/" versioned directory may be
specified, see systemd.v(7) for details.
In place of the directory path a ".v/" versioned directory may
be specified, see systemd.v(7) for details.
Added in version 249.
--force
Skip safety checks and attach or detach images (with
extensions) without first ensuring that the units are not
running, and do not insist that the extension-release.NAME
file in the extension image has to match the image filename.
Added in version 252.
-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=
Execute operation on a local container. Specify a container
name to connect to, optionally prefixed by a user name to
connect as and a separating "@" character. If the special
string ".host" is used in place of the container name, a
connection to the local system is made (which is useful to
connect to a specific user's user bus: "--user
[email protected]"). If the "@" syntax is not used, the
connection is made as root user. If the "@" syntax is used
either the left hand side or the right hand side may be
omitted (but not both) in which case the local user name and
".host" are implied.
--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.
Portable service images are preferably stored in
/var/lib/portables/, but are also searched for in /etc/portables/,
/run/systemd/portables/, /usr/local/lib/portables/ and
/usr/lib/portables/. It's recommended not to place image files
directly in /etc/portables/ or /run/systemd/portables/ (as these
are generally not suitable for storing large or non-textual data),
but use these directories only for linking images located
elsewhere into the image search path.
When a portable service image is attached, matching unit files are
copied onto the host into the /etc/systemd/system.attached/ and
/run/systemd/system.attached/ directories. When an image is
detached, the unit files are removed again from these directories.
When portable service images are attached a "profile" drop-in is
linked in, which may be used to enforce additional security (and
other) restrictions locally. Four profile drop-ins are defined by
default, and shipped in /usr/lib/systemd/portable/profile/.
Additional, local profiles may be defined by placing them in
/etc/systemd/portable/profile/. The default profiles are:
Table 2. Profiles
┌───────────┬──────────────────────────┐
│ Name │ Description │
├───────────┼──────────────────────────┤
│ default │ This is the default │
│ │ profile if no other │
│ │ profile name is set via │
│ │ the --profile= (see │
│ │ above). It's fairly │
│ │ restrictive, but should │
│ │ be useful for common, │
│ │ unprivileged system │
│ │ workloads. This includes │
│ │ write access to the │
│ │ logging framework, as │
│ │ well as IPC access to │
│ │ the D-Bus system. │
├───────────┼──────────────────────────┤
│ nonetwork │ Very similar to default, │
│ │ but networking is turned │
│ │ off for any services of │
│ │ the portable service │
│ │ image. │
├───────────┼──────────────────────────┤
│ strict │ A profile with very │
│ │ strict settings. This │
│ │ profile excludes IPC │
│ │ (D-Bus) and network │
│ │ access. │
├───────────┼──────────────────────────┤
│ trusted │ A profile with very │
│ │ relaxed settings. In │
│ │ this profile the │
│ │ services run with full │
│ │ privileges. │
└───────────┴──────────────────────────┘
For details on these profiles and their effects see their precise
definitions, e.g.
/usr/lib/systemd/portable/profile/default/service.conf and
similar.
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
Pager to use when --no-pager is not given. $SYSTEMD_PAGER is
used if set; otherwise $PAGER is used. If neither
$SYSTEMD_PAGER nor $PAGER are set, a set of well-known pager
implementations is tried in turn, including less(1) and
more(1), until one is found. If no pager implementation is
discovered, no pager is invoked. Setting those environment
variables to an empty string or the value "cat" is equivalent
to passing --no-pager.
Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER and
$PAGER can only be used to disable the pager (with "cat" or
""), and are otherwise 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
Common pager commands like less(1), in addition to "paging",
i.e. scrolling through the output, support opening of or
writing to other files and running arbitrary shell commands.
When commands are invoked with elevated privileges, for
example under sudo(8) or pkexec(1), the pager becomes a
security boundary. Care must be taken that only programs with
strictly limited functionality are used as pagers, and
unintended interactive features like opening or creation of
new files or starting of subprocesses are not allowed. "Secure
mode" for the pager may be enabled as described below, if the
pager supports that (most pagers are not written in a way that
takes this into consideration). It is recommended to either
explicitly enable "secure mode" or to completely disable the
pager using --no-pager or PAGER=cat when allowing untrusted
users to execute commands with elevated privileges.
This option takes a boolean argument. When set to true, the
"secure mode" of the pager is enabled. In "secure mode",
LESSSECURE=1 will be set when invoking the pager, which
instructs the pager to disable commands that open or create
new files or start new subprocesses. Currently only less(1) is
known to understand this variable and implement "secure mode".
When set to false, no limitation is placed on the pager.
Setting SYSTEMD_PAGERSECURE=0 or not removing it from the
inherited environment may allow the user to invoke arbitrary
commands.
When $SYSTEMD_PAGERSECURE is not set, systemd tools attempt to
automatically figure out if "secure mode" should be enabled
and whether the pager supports it. "Secure mode" is enabled if
the effective UID is not the same as the owner of the login
session, see geteuid(2) and sd_pid_get_owner_uid(3), or when
running under sudo(8) or similar tools ($SUDO_UID is set [2]).
In those cases, SYSTEMD_PAGERSECURE=1 will be set and pagers
which are not known to implement "secure mode" will not be
used at all. Note that this autodetection only covers the most
common mechanisms to elevate privileges and is intended as
convenience. It is recommended to explicitly set
$SYSTEMD_PAGERSECURE or disable the pager.
Note that if the $SYSTEMD_PAGER or $PAGER variables are to be
honoured, other than to disable the pager,
$SYSTEMD_PAGERSECURE must be set too.
$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-sysext(8), org.freedesktop.portable1(5),
systemd-portabled.service(8), importctl(1)
1. Portable Services
https://systemd.io/PORTABLE_SERVICES
2. It is recommended for other tools to set and check $SUDO_UID
as appropriate, treating it is a common interface.
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 2025-08-11. (At that
time, the date of the most recent commit that was found in the
repository was 2025-08-11.) 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
[email protected]
systemd 258~rc2 PORTABLECTL(1)
Pages that refer to this page: importctl(1), org.freedesktop.portable1(5), systemd.directives(7), systemd.index(7), systemd-portabled.service(8), systemd-repart(8)
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