snap(8) System Manager's Manual snap(8)
NAME
snap - Tool to interact with snaps
SYNOPSIS
snap [OPTIONS]
DESCRIPTION
The snap command lets you install, configure, refresh and remove snaps.
Snaps are packages that work across many different Linux distributions,
enabling secure delivery and operation of the latest apps and utili-
ties.
OPTIONS
COMMANDS
abort
Abort a pending change
The abort command attempts to abort a change that still has pending
tasks.
Usage: snap [OPTIONS] abort [abort-OPTIONS]
--last Select last change of given type (install, refresh, remove, try,
auto-refresh, etc.). A question mark at the end of the type
means to do nothing (instead of returning an error) if no change
of the given type is found. Note the question mark could need
protecting from the shell.
ack
Add an assertion to the system
The ack command tries to add an assertion to the system assertion data-
base.
The assertion may also be a newer revision of a pre-existing assertion
that it will replace.
To succeed the assertion must be valid, its signature verified with a
known public key and the assertion consistent with and its prerequisite
in the database.
alias
Set up a manual alias
The alias command aliases the given snap application to the given
alias.
Once this manual alias is setup the respective application command can
be invoked just using the alias.
Usage: snap [OPTIONS] alias [alias-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
aliases
List aliases in the system
The aliases command lists all aliases available in the system and their
status.
$ snap aliases <snap>
Lists only the aliases defined by the specified snap.
changes
List system changes
The changes command displays a summary of system changes performed re-
cently.
Usage: snap [OPTIONS] changes [changes-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
check-snapshot
Check a snapshot
The check-snapshot command verifies the user, system and configuration
data of the snaps included in the specified snapshot.
The check operation runs the same data integrity verification that is
performed when a snapshot is restored.
By default, this command checks all the data in a snapshot. Alterna-
tively, you can specify the data of which snaps to check, or for which
users, or a combination of these.
If a snap is included in a check-snapshot operation, excluding its sys-
tem and configuration data from the check is not currently possible.
This restriction may be lifted in the future.
Usage: snap [OPTIONS] check-snapshot [check-snapshot-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--users
Check data of only specific users (comma-separated) (default:
all users)
components
List available and installed components for installed snaps
The components command displays a summary of the components that are
installed and available for the set of currently installed snaps.
Components for specific installed snaps can be queried by providing
snap names as positional arguments.
connect
Connect a plug to a slot
The connect command connects a plug to a slot. It may be called in the
following ways:
$ snap connect <snap>:<plug> <snap>:<slot>
Connects the provided plug to the given slot.
$ snap connect <snap>:<plug> <snap>
Connects the specific plug to the only slot in the provided snap that
matches the connected interface. If more than one potential slot ex-
ists, the command fails.
$ snap connect <snap>:<plug>
Connects the provided plug to the slot in the core snap with a name
matching the plug name.
Usage: snap [OPTIONS] connect [connect-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
connections
List interface connections
The connections command lists connections between plugs and slots in
the system.
Unless <snap> is provided, the listing is for connected plugs and slots
for all snaps in the system. In this mode, pass --all to also list un-
connected plugs and slots.
$ snap connections <snap>
Lists connected and unconnected plugs and slots for the specified snap.
Usage: snap [OPTIONS] connections [connections-OPTIONS]
--all Show connected and unconnected plugs and slots
create-cohort
Create cohort keys for a set of snaps
The create-cohort command creates a set of cohort keys for a given set
of snaps.
A cohort is a view or snapshot of a snap's "channel map" at a given
point in time that fixes the set of revisions for the snap given other
constraints (e.g. channel or architecture). The cohort is then identi-
fied by an opaque per-snap key that works across systems. Installations
or refreshes of the snap using a given cohort key would use a fixed re-
vision for up to 90 days, after which a new set of revisions would be
fixed under that same cohort key and a new 90 days window started.
debug
Run debug commands
The debug command contains a selection of additional sub-commands.
Debug commands can be removed without notice and may not work on non-
development systems.
debug api
Execute raw query to snapd API
Execute a raw query to snapd API. Complex input can be read from stdin,
while output is printed to stdout. See examples below:
List all snaps: $ snap debug api /v2/snaps
Find snaps with name foo: $ snap debug api '/v2/find?name=foo'
Request refresh of snap 'some-snap': $ echo '{"action": "refresh"}' |
snap debug api -X POST \
-H 'Content-Type: application/json' /v2/snaps/some-snap
Usage: snap [OPTIONS] debug api [api-OPTIONS]
--snap-socket
Use snap access socket
-H, --header
Set header (can be repeated multiple times), header kind and
value are separated with ': '
-X, --request
HTTP method to use (defaults to GET)
--fail Fail on request errors
debug confinement
Print the confinement mode the system operates in
The confinement command will print the confinement mode (strict, par-
tial or none) the system operates in.
debug connectivity
Check network connectivity status
The connectivity command checks the network connectivity of snapd.
debug execution
Obtain information about execution aspects of snap toolchain commands
Display debugging information about aspects of snap toolchain execu-
tion, such as reexecution, tools location etc.
debug execution apparmor
Show apparmor
debug execution internal-tool
Show internal tool execution info
debug execution snap
Show snap execution info
debug migrate-home
Migrate snaps' directory to ~/Snap.
Migrate snaps' directory to ~/Snap.
Usage: snap [OPTIONS] debug migrate-home [migrate-home-OPTIONS]
--no-wait
debug paths
Print system paths
The paths command prints the list of paths detected and used by snapd.
debug sandbox-features
Print sandbox features available on the system
The sandbox command prints tags describing features of individual sand-
box components used by snapd on a given system.
Usage: snap [OPTIONS] debug sandbox-features [sandbox-features-OPTIONS]
--required
Ensure that given backend:feature is available
debug seeding
Obtain seeding and preseeding details
Obtain seeding and preseeding details
Usage: snap [OPTIONS] debug seeding [seeding-OPTIONS]
--unicode <default: "auto">
debug stacktraces
Obtain stacktraces of all snapd goroutines
Obtain stacktraces of all snapd goroutines.
debug state
Inspect a snapd state file.
Inspect a snapd state file, bypassing snapd API.
Usage: snap [OPTIONS] debug state [state-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--changes
List all changes
--task ID of the task to inspect
--change
ID of the change to inspect
--check
Check change consistency
--connections
List all connections
--connection
Show details of the matching connections (snap or
snap:plug,snap:slot or snap:plug-or-slot
--is-seeded
Output seeding status (true or false)
--dot Dot (graphviz) output
--no-hold
Omit tasks in 'Hold' state in the change output
debug timings
Get the timings of the tasks of a change
The timings command displays details about the time each task runs.
Usage: snap [OPTIONS] debug timings [timings-OPTIONS]
--last Select last change of given type (install, refresh, remove, try,
auto-refresh, etc.). A question mark at the end of the type
means to do nothing (instead of returning an error) if no change
of the given type is found. Note the question mark could need
protecting from the shell.
--ensure
Show timings for a change related to the given Ensure activity
(one of: auto-refresh, become-operational, refresh-catalogs, re-
fresh-hints, seed)
--all Show timings for all executions of the given Ensure or startup
activity, not just the latest
--startup
Show timings for the startup of given subsystem (one of: load-
state, ifacemgr)
--verbose
Show more information
debug validate-seed
Validate snap seed
Validate correctness of snap seed located in the directory containing
seed.yaml file.
disable
Disable a snap in the system
The disable command disables a snap. The binaries and services of the
snap will no longer be available, but all the data is still available
and the snap can easily be enabled again.
Usage: snap [OPTIONS] disable [disable-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
disconnect
Disconnect a plug from a slot
The disconnect command disconnects a plug from a slot. It may be
called in the following ways:
$ snap disconnect <snap>:<plug> <snap>:<slot>
Disconnects the specific plug from the specific slot.
$ snap disconnect <snap>:<slot or plug>
Disconnects everything from the provided plug or slot. The snap name
may be omitted for the core snap.
When an automatic connection is manually disconnected, its disconnected
state is retained after a snap refresh. The --forget flag can be added
to the disconnect command to reset this behaviour, and consequently re-
enable an automatic reconnection after a snap refresh.
Usage: snap [OPTIONS] disconnect [disconnect-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--forget
Forget remembered state about the given connection.
download
Download the given snap
The download command downloads the given snap and its supporting asser-
tions to the current directory with .snap and .assert file extensions,
respectively.
Usage: snap [OPTIONS] download [download-OPTIONS]
--channel
Use this channel instead of stable
--edge Install from the edge channel
--beta Install from the beta channel
--candidate
Install from the candidate channel
--stable
Install from the stable channel
--revision
Download the given revision of a snap
--basename
Use this basename for the snap and assertion files (defaults to
<snap>_<revision>)
--target-directory
Download to this directory (defaults to the current directory)
--cohort
Download from the given cohort
enable
Enable a snap in the system
The enable command enables a snap that was previously disabled.
Usage: snap [OPTIONS] enable [enable-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
export-snapshot
Export a snapshot
Export a snapshot to the given filename.
find
Find packages to install
The find command queries the store for available packages.
With the --private flag, which requires the user to be logged-in to the
store (see 'snap help login'), it instead searches for private snaps
that the user has developer access to, either directly or through the
store's collaboration feature.
A green check mark (given color and unicode support) after a publisher
name indicates that the publisher has been verified.
Usage: snap [OPTIONS] find [find-OPTIONS]
Aliases: search
--private
Search private snaps.
--narrow
Only search for snaps in “stable”.
--section [="show-all-sections-please"] <default: "no-section-speci-
fied">
Restrict the search to a given section.
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
forget
Delete a snapshot
The forget command deletes a snapshot. This operation can not be un-
done.
A snapshot contains archives for the user, system and configuration
data of each snap included in the snapshot.
By default, this command forgets all the data in a snapshot. Alterna-
tively, you can specify the data of which snaps to forget.
Usage: snap [OPTIONS] forget [forget-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
get
Print configuration options
The get command prints configuration options for the provided snap.
$ snap get snap-name username
frank
If multiple option names are provided, the corresponding values are re-
turned:
$ snap get snap-name username password
Key Value
username frank
password ...
Nested values may be retrieved via a dotted path:
$ snap get snap-name author.name
frank
Usage: snap [OPTIONS] get [get-OPTIONS]
-t Strict typing with nulls and quoted strings
-d Always return document, even with single key
-l Always return list, even with single key
help
Show help about a command
The help command displays information about snap commands.
Usage: snap [OPTIONS] help [help-OPTIONS]
--all Show a short summary of all commands
import-snapshot
Import a snapshot
Import an exported snapshot set to the system. The snapshot is imported
with a new snapshot ID and can be restored using the restore command.
Usage: snap [OPTIONS] import-snapshot [import-snapshot-OPTIONS]
--abs-time
info
Show detailed information about snaps
The info command shows detailed information about snaps.
The snaps can be specified by name or by path; names are looked for
both in the store and in the installed snaps; paths can refer to a
.snap file, or to a directory that contains an unpacked snap suitable
for 'snap try' (an example of this would be the 'prime' directory
snapcraft produces).
Usage: snap [OPTIONS] info [info-OPTIONS]
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--verbose
Include more details on the snap (expanded notes, base, etc.)
install
Install snaps on the system
The install command installs the named snaps on the system.
To install multiple instances of the same snap, append an underscore
and a unique identifier (for each instance) to a snap's name.
Parallel instances are installed with --unaliased passed implicitly to
avoid conflicts with existing installs. This behaviour can be altered
by passing --prefer which will enable all aliases of the given snap in
preference to conflicting aliases of other snaps whose automatic
aliases will be disabled and manual aliases will be removed.
With no further options, the snaps are installed tracking the stable
channel, with strict security confinement. All available channels of a
snap are listed in its 'snap info' output.
When --revision is used, a later refresh will typically undo the revi-
sion override, taking the snap back to the current revision of the
channel it's tracking.
Use --name to set the instance name when installing from snap file.
Usage: snap [OPTIONS] install [install-OPTIONS]
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--no-wait
Do not wait for the operation to finish but just print the
change id.
--channel
Use this channel instead of stable
--edge Install from the edge channel
--beta Install from the beta channel
--candidate
Install from the candidate channel
--stable
Install from the stable channel
--devmode
Put snap in development mode and disable security confinement
--jailmode
Put snap in enforced confinement mode
--classic
Put snap in classic mode and disable security confinement
--revision
Install the given revision of a snap
--dangerous
Install the given snap file even if there are no pre-acknowl-
edged signatures for it, meaning it was not verified and could
be dangerous (--devmode implies this)
--unaliased
Install the given snap without enabling its automatic aliases
--prefer
Enable all aliases of the given snap in preference to conflict-
ing aliases of other snaps
--name Install the snap file under the given instance name
--cohort
Install the snap in the given cohort
--ignore-validation
Ignore validation by other snaps blocking the installation
--transaction <default: "per-snap">
Have one transaction per-snap or one for all the specified snaps
--quota-group
Add the snap to a quota group on install
interface
Show details of snap interfaces
The interface command shows details of snap interfaces.
If no interface name is provided, a list of interface names with at
least one connection is shown, or a list of all interfaces if --all is
provided.
Usage: snap [OPTIONS] interface [interface-OPTIONS]
--attrs
Show interface attributes
--all Include unused interfaces
known
Show known assertions of the provided type
The known command shows known assertions of the provided type. If
header=value pairs are provided after the assertion type, the asser-
tions shown must also have the specified headers matching the provided
values.
Usage: snap [OPTIONS] known [known-OPTIONS]
--remote
Query the store for the assertion, via snapd if possible
--direct
Query the store for the assertion, without attempting to go via
snapd
list
List installed snaps
The list command displays a summary of snaps installed in the current
system.
A green check mark (given color and unicode support) after a publisher
name indicates that the publisher has been verified.
Usage: snap [OPTIONS] list [list-OPTIONS]
--all Show all revisions
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
login
Authenticate to snapd and the store
The login command authenticates the user to snapd and the snap store,
and saves credentials into the ~/.snap/auth.json file. Further communi-
cation with snapd will then be made using those credentials.
It's not necessary to log in to interact with snapd. Doing so, however,
enables interactions without sudo, as well as some some developer-ori-
ented features as detailed in the help for the find, install and re-
fresh commands.
An account can be set up at https://login.ubuntu.com
logout
Log out of snapd and the store
The logout command logs the current user out of snapd and the store.
logs
Retrieve logs for services
The logs command fetches logs of the given services and displays them
in chronological order.
Usage: snap [OPTIONS] logs [logs-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
-n <default: "10">
Show only the given number of lines, or 'all'.
-f Wait for new lines and print them as they come in.
model
Get the active model for this device
The model command returns the active model assertion information for
this device.
By default, only the essential model identification information is in-
cluded in the output, but this can be expanded to include all of an as-
sertion's non-meta headers.
The verbose output is presented in a structured, yaml-like format.
Similarly, the active serial assertion can be used for the output in-
stead of the model assertion.
Usage: snap [OPTIONS] model [model-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--serial
Print the serial assertion instead of the model assertion.
--verbose
Print all specific assertion fields.
--assertion
Print the raw assertion.
okay
Acknowledge warnings
The okay command acknowledges the warnings listed with 'snap warnings'.
Once acknowledged a warning won't appear again unless it re-occurrs and
sufficient time has passed.
pack
Pack the given directory as a snap
The pack command packs the given snap-dir as a snap and writes the re-
sult to target-dir. If target-dir is omitted, the result is written to
current directory. If both source-dir and target-dir are omitted, the
pack command packs the current directory.
The default file name for a snap can be derived entirely from its
snap.yaml, but in some situations it's simpler for a script to feed the
filename in. In those cases, --filename can be given to override the
default. If this filename is not absolute it will be taken as relative
to target-dir.
When used with --check-skeleton, pack only checks whether snap-dir con-
tains valid snap metadata and raises an error otherwise. Application
commands listed in snap metadata file, but appearing with incorrect
permission bits result in an error. Commands that are missing from
snap-dir are listed in diagnostic messages.
Usage: snap [OPTIONS] pack [pack-OPTIONS]
--check-skeleton
Validate snap-dir metadata only
--filename
Output to this filename
--compression
Compression to use (e.g. xz or lzo)
prefer
Enable aliases from a snap, disabling any conflicting aliases
The prefer command enables all aliases of the given snap in preference
to conflicting aliases of other snaps whose aliases will be disabled
(or removed, for manual ones).
Usage: snap [OPTIONS] prefer [prefer-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
prepare-image
Prepare a device image
The prepare-image command performs some of the steps necessary for cre-
ating device images.
For core images it is not invoked directly but usually via ubuntu-im-
age.
For preparing classic images it supports a --classic mode
Usage: snap [OPTIONS] prepare-image [prepare-image-OPTIONS]
--classic
Enable classic mode to prepare a classic model image
--preseed
Preseed (UC20+ only)
--preseed-sign-key
Name of the key to use to sign preseed assertion, otherwise use
the default key
--apparmor-features-dir
Optional path to apparmor kernel features directory (UC20+ only)
--sysfs-overlay
Optional sysfs overlay to be used when running preseeding steps
--arch Specify an architecture for snaps for --classic when the model
does not
--channel
The channel to use
--snap <snap>[=<channel>]
Include the given snap from the store or a local file and/or
specify the channel to track for the given snap
--comp <snap>+<comp>
Include the given component from the store or a local file
--revisions
Specify a seeds.manifest file referencing the exact revisions of
the provided snaps which should be installed
--write-revisions [="./seed.manifest"]
Writes a manifest file containing references to the exact snap
revisions used for the image. A path for the manifest is op-
tional.
quota
Show quota group for a set of snaps
The quota command shows information about a quota group, including the
set of snaps and any sub-groups it contains, as well as its resource
constraints and the current usage of those constrained resources.
quotas
Show quota groups
The quotas command shows all quota groups.
reboot
Reboot into selected system and mode
The reboot command reboots the system into a particular mode of the se-
lected recovery system.
When called without a system label and without a mode it will just
trigger a regular reboot.
When called without a label, the current system will be used for "run"
mode. The default recovery system will be used for "recover", "factory-
reset" and "install" modes.
Note that the "run" mode is only available for the current system.
Usage: snap [OPTIONS] reboot [reboot-OPTIONS]
--run Boot into run mode
--install
Boot into install mode
--recover
Boot into recover mode
--factory-reset
Boot into factory-reset mode
recovery
List available recovery systems
The recovery command lists the available recovery systems.
With --show-keys it displays recovery keys that can be used to unlock
the encrypted partitions if the device-specific automatic unlocking
does not work.
Usage: snap [OPTIONS] recovery [recovery-OPTIONS]
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--show-keys
Show recovery keys (if available) to unlock encrypted parti-
tions.
refresh
Refresh snaps in the system
The refresh command updates the specified snaps, or all snaps in the
system if none are specified.
With no further options, the snaps are refreshed to the current revi-
sion of the channel they're tracking, preserving their confinement op-
tions. All available channels of a snap are listed in its 'snap info'
output.
When --revision is used, a later refresh will typically undo the revi-
sion override.
Hold (--hold) is used to postpone snap refresh updates for all snaps
when no snaps are specified, or for the specified snaps.
When no snaps are specified --hold is only effective on auto-refreshes
and will not block either general refresh requests from 'snap refresh'
or specific snap requests from 'snap refresh target-snap'.
When snaps are specified --hold is effective on both their auto-re-
freshes and general refresh requests from 'snap refresh'. However, spe-
cific snap requests from 'snap refresh target-snap' remain unblocked
and will proceed.
Usage: snap [OPTIONS] refresh [refresh-OPTIONS]
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--no-wait
Do not wait for the operation to finish but just print the
change id.
--channel
Use this channel instead of stable
--edge Install from the edge channel
--beta Install from the beta channel
--candidate
Install from the candidate channel
--stable
Install from the stable channel
--devmode
Put snap in development mode and disable security confinement
--jailmode
Put snap in enforced confinement mode
--classic
Put snap in classic mode and disable security confinement
--amend
Allow refresh attempt on snap unknown to the store
--revision
Refresh to the given revision
--cohort
Refresh the snap into the given cohort
--leave-cohort
Refresh the snap out of its cohort
--list Show the new versions of snaps that would be updated with the
next refresh
--time Show auto refresh information but do not perform a refresh
--ignore-validation
Ignore validation by other snaps blocking the refresh
--transaction <default: "per-snap">
Have one transaction per-snap or one for all the specified snaps
--hold [="forever"]
Hold refreshes for a specified duration (or forever, if no value
is specified)
--unhold
Remove refresh hold
remodel
Remodel this device
The remodel command changes the model assertion of the device, either
to a new revision or a full new model.
In the process it applies any implied changes to the device: new re-
quired snaps, new kernel or gadget etc.
Snaps and assertions are downloaded from the store unless they are pro-
vided as local files specified by --snap and --assertion options. If
using these options, it is expected that all the needed snaps and as-
sertions are provided locally, otherwise the remodel will fail.
Usage: snap [OPTIONS] remodel [remodel-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--snap Use one or more locally available snaps.
--assertion
Use one or more locally available assertion files.
--offline
Use only pre-installed and locally provided snaps and asser-
tions. Providing any snaps or assertions locally implies --off-
line.
remove
Remove snaps from the system
The remove command removes the named snap instance from the system.
By default all the snap revisions are removed, including their data and
the common data directory. When a --revision option is passed only the
specified revision is removed.
Unless automatic snapshots are disabled, a snapshot of all data for the
snap is saved upon removal, which is then available for future restora-
tion with snap restore. The --purge option disables automatically cre-
ating snapshots.
Usage: snap [OPTIONS] remove [remove-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--revision
Remove only the given revision
--purge
Remove the snap without saving a snapshot of its data
--terminate
Terminate running processes associated with a snap before re-
moval
remove-quota
Remove quota group
The remove-quota command removes the given quota group.
Currently, only quota groups with no sub-groups can be removed. In or-
der to remove a quota group with sub-groups, the sub-groups must first
be removed until there are no sub-groups for the group, then the group
itself can be removed.
Usage: snap [OPTIONS] remove-quota [remove-quota-OPTIONS]
--no-wait
restart
Restart services
The restart command restarts the given services.
If the --reload option is given, for each service whose app has a
reload command, a reload is performed instead of a restart.
Usage: snap [OPTIONS] restart [restart-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--system
The operation should only affect system services.
--user The operation should only affect user services for the current
user.
--users
If provided and set to 'all', the operation should affect ser-
vices for all users.
--reload
If the service has a reload command, use it instead of restart-
ing.
restore
Restore a snapshot
The restore command replaces the current user, system and configuration
data of included snaps, with the corresponding data from the specified
snapshot.
By default, this command restores all the data in a snapshot. Alterna-
tively, you can specify the data of which snaps to restore, or for
which users, or a combination of these.
If a snap is included in a restore operation, excluding its system and
configuration data from the restore is not currently possible. This re-
striction may be lifted in the future.
Usage: snap [OPTIONS] restore [restore-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--users
Restore data of only specific users (comma-separated) (default:
all users)
revert
Reverts the given snap to the previous state
The revert command reverts the given snap to its state before the lat-
est refresh. This will reactivate the previous snap revision, and will
use the original data that was associated with that revision, discard-
ing any data changes that were done by the latest revision. As an ex-
ception, data which the snap explicitly chooses to share across revi-
sions is not touched by the revert process.
Usage: snap [OPTIONS] revert [revert-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--devmode
Put snap in development mode and disable security confinement
--jailmode
Put snap in enforced confinement mode
--classic
Put snap in classic mode and disable security confinement
--revision
Revert to the given revision
run
Run the given snap command
The run command executes the given snap command with the right confine-
ment and environment.
Usage: snap [OPTIONS] run [run-OPTIONS] <NAME-OF-SNAP>.<NAME-OF-APP>
[<SNAP-APP-ARG>...]
--shell
Run a shell instead of the command (useful for debugging)
--debug-log
Enable debug logging during early snap startup phases
--strace [="with-strace"] <default: "no-strace">
Run the command under strace (useful for debugging). Extra
strace options can be specified as well here. Pass --raw to
strace early snap helpers.
--gdbserver [=":0"] <default: "no-gdbserver">
Run the command with gdbserver
--trace-exec
Display exec calls timing data
save
Save a snapshot of the current data
The save command creates a snapshot of the current user, system and
configuration data for the given snaps.
By default, this command saves the data of all snaps for all users.
Alternatively, you can specify the data of which snaps to save, or for
which users, or a combination of these.
If a snap is included in a save operation, excluding its system and
configuration data from the snapshot is not currently possible. This
restriction may be lifted in the future.
Usage: snap [OPTIONS] save [save-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
short relative times.
--users
Snapshot data of only specific users (comma-separated) (default:
all users)
saved
List currently stored snapshots
The saved command displays a list of snapshots that have been created
previously with the 'save' command.
Usage: snap [OPTIONS] saved [saved-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
short relative times.
--id Show only a specific snapshot.
services
Query the status of services
The services command lists information about the services specified, or
about the services in all currently installed snaps.
If executed as root user, the 'Startup' column of any user service will
be whether it's globally enabled (i.e systemctl is-enabled). To view
the actual 'Startup'|'Current' status of the user services for the root
user itself, --user can be provided.
If executed as a non-root user, the 'Startup'|'Current' status of user
services will be the current status for the invoking user. To view the
global enablement status of user services, --global can be provided.
Usage: snap [OPTIONS] services [services-OPTIONS]
-g, --global
Show the global enable status for user services instead of the
status for the current user.
-u, --user
Show the current status of the user services instead of the
global enable status.
set
Change configuration options
The set command changes the provided configuration options as re-
quested.
$ snap set snap-name username=frank password=$PASSWORD
All configuration changes are persisted at once, and only after the
snap's configuration hook returns successfully.
Nested values may be modified via a dotted path:
$ snap set snap-name author.name=frank
Configuration option may be unset with exclamation mark:
$ snap set snap-name author!
Usage: snap [OPTIONS] set [set-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
-t Parse the value strictly as JSON document
-s Parse the value as a string
set-quota
Create or update a quota group.
The set-quota command updates or creates a quota group with the speci-
fied set of snaps.
A quota group sets resource limits on the set of snaps or snap services
it contains. Snaps can be at most in one quota group but quota groups
can be nested. Nested quota groups are subject to the restriction that
the total sum of each existing quota in sub-groups cannot exceed that
of the parent group the nested groups are part of.
All provided snaps are appended to the group; to remove a snap from a
quota group, the entire group must be removed with remove-quota and
recreated without the snap. To remove a sub-group from the quota group,
the sub-group must be removed directly with the remove-quota command.
To set limits on individual services, one or more services can be
placed into a sub-group. The respective snap for each service must be-
long to the sub-group's parent group. These sub-groups will have the
same limitations as nested groups which means their combined resource
usage cannot exceed the resource limits set for the parent group. Sub-
groups which contain services cannot have their own journal quotas set,
and instead automatically inherit any journal quota their parent quota
group may have.
The memory limit for a quota group can be increased but not decreased.
To decrease the memory limit for a quota group, the entire group must
be removed with the remove-quota command and recreated with a lower
limit. Increasing the memory limit for a quota group does not restart
any services associated with snaps in the quota group.
The CPU limit for a quota group can be both increased and decreased af-
ter being set on a quota group. The CPU limit can be specified as a
single percentage which means that the quota group is allowed an over-
all percentage of the CPU resources. Setting it to 50% means that the
quota group is allowed to use up to 50% of all CPU cores in the allowed
CPU set. Setting the percentage to 2x100% means that the quota group is
allowed up to 100% on two cpu cores.
The CPU set limit for a quota group can be modified to include new
cpus, or to remove existing cpus from the quota already set.
The threads limit for a quota group can be increased but not decreased.
To decrease the threads limit for a quota group, the entire group must
be removed with the remove-quota command and recreated with a lower
limit.
The journal limits can be increased and decreased after being set on a
group. Setting a journal limit will cause the snaps in the group to be
put into the same journal namespace. This will affect the behaviour of
the log command.
New quotas can be set on existing quota groups, but existing quotas
cannot be removed from a quota group, without removing and recreating
the entire group.
Adding new snaps to a quota group will result in all non-disabled ser-
vices in that snap being restarted.
An existing sub group cannot be moved from one parent to another.
Usage: snap [OPTIONS] set-quota [set-quota-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--memory [=]
Memory quota
--cpu [=]
CPU quota
--cpu-set [=]
CPU set quota
--threads [=]
Threads quota
--journal-size [=]
Journal size quota
--journal-rate-limit [=]
Journal rate limit as <message count>/<message period>
--parent [=]
Parent quota group
start
Start services
The start command starts, and optionally enables, the given services.
Usage: snap [OPTIONS] start [start-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--system
The operation should only affect system services.
--user The operation should only affect user services for the current
user.
--users
If provided and set to 'all', the operation should affect ser-
vices for all users.
--enable
As well as starting the service now, arrange for it to be
started on boot.
stop
Stop services
The stop command stops, and optionally disables, the given services.
Usage: snap [OPTIONS] stop [stop-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--system
The operation should only affect system services.
--user The operation should only affect user services for the current
user.
--users
If provided and set to 'all', the operation should affect ser-
vices for all users.
--disable
As well as stopping the service now, arrange for it to no longer
be started on boot.
switch
Switches snap to a different channel
The switch command switches the given snap to a different channel with-
out doing a refresh. All available channels of a snap are listed in its
'snap info' output.
Usage: snap [OPTIONS] switch [switch-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--channel
Use this channel instead of stable
--edge Install from the edge channel
--beta Install from the beta channel
--candidate
Install from the candidate channel
--stable
Install from the stable channel
--cohort
Switch the snap into the given cohort
--leave-cohort
Switch the snap out of its cohort
tasks
List a change's tasks
The tasks command displays a summary of tasks associated with an indi-
vidual change.
Usage: snap [OPTIONS] tasks [tasks-OPTIONS]
Aliases: change
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--last Select last change of given type (install, refresh, remove, try,
auto-refresh, etc.). A question mark at the end of the type
means to do nothing (instead of returning an error) if no change
of the given type is found. Note the question mark could need
protecting from the shell.
try
Test an unpacked snap in the system
The try command installs an unpacked snap into the system for testing
purposes. The unpacked snap content continues to be used even after
installation, so non-metadata changes there go live instantly. Metadata
changes such as those performed in snap.yaml will require reinstalla-
tion to go live.
If snap-dir argument is omitted, the try command will attempt to infer
it if either snapcraft.yaml file and prime directory or meta/snap.yaml
file can be found relative to current working directory.
Usage: snap [OPTIONS] try [try-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
--devmode
Put snap in development mode and disable security confinement
--jailmode
Put snap in enforced confinement mode
--classic
Put snap in classic mode and disable security confinement
unalias
Remove a manual alias, or the aliases for an entire snap
The unalias command removes a single alias if the provided argument is
a manual alias, or disables all aliases of a snap, including manual
ones, if the argument is a snap name.
Usage: snap [OPTIONS] unalias [unalias-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
unset
Remove configuration options
The unset command removes the provided configuration options as re-
quested.
$ snap unset snap-name name address
All configuration changes are persisted at once, and only after the
snap's configuration hook returns successfully.
Nested values may be removed via a dotted path:
$ snap unset snap-name user.name
Usage: snap [OPTIONS] unset [unset-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the
change id.
validate
List or apply validation sets
The validate command lists or applies validation sets that state which
snaps are required or permitted to be installed together, optionally
constrained to fixed revisions.
A validation set can either be in monitoring mode, in which case its
constraints aren't enforced, or in enforcing mode, in which case snapd
will not allow operations which would result in snaps breaking the val-
idation set's constraints.
Usage: snap [OPTIONS] validate [validate-OPTIONS]
--monitor
Monitor the given validations set
--enforce
Enforce the given validation set
--forget
Forget the given validation set
--refresh
Refresh or install snaps to satisfy enforced validation sets
--color <default: "auto">
Use a little bit of color to highlight some things.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--no-wait
Do not wait for the operation to finish but just print the
change id.
version
Show version details
The version command displays the versions of the running client,
server, and operating system.
wait
Wait for configuration
The wait command waits until a configuration becomes true.
warnings
List warnings
The warnings command lists the warnings that have been reported to the
system.
Once warnings have been listed with 'snap warnings', 'snap okay' may be
used to silence them. A warning that's been silenced in this way will
not be listed again unless it happens again, _and_ a cooldown time has
passed.
Warnings expire automatically, and once expired they are forgotten.
Usage: snap [OPTIONS] warnings [warnings-OPTIONS]
--abs-time
Display absolute times (in RFC 3339 format). Otherwise, display
relative times up to 60 days, then YYYY-MM-DD.
--unicode <default: "auto">
Use a little bit of Unicode to improve legibility.
--all Show all warnings
--verbose
Show more information
watch
Watch a change in progress
The watch command waits for the given change-id to finish and shows
progress (if available).
Usage: snap [OPTIONS] watch [watch-OPTIONS]
--last Select last change of given type (install, refresh, remove, try,
auto-refresh, etc.). A question mark at the end of the type
means to do nothing (instead of returning an error) if no change
of the given type is found. Note the question mark could need
protecting from the shell.
whoami
Show the email the user is logged in with
The whoami command shows the email the user is logged in with.
NOTES
1. Online documentation
https://docs.snapcraft.io
BUGS
Please report all bugs with https://bugs.launchpad.net/snapd/+filebug
15 January 2025 snap(8)
Generated by dwww version 1.14 on Sun Apr 6 16:09:48 CEST 2025.