1snap(8) System Manager's Manual snap(8)
2
6 snap - Tool to interact with snaps
7
9 snap [OPTIONS]
10
12 The snap command lets you install, configure, refresh and remove snaps.
13 Snaps are packages that work across many different Linux distributions,
14 enabling secure delivery and operation of the latest apps and utili‐
15 ties.
16
19 abort
20 Abort a pending change
21 The abort command attempts to abort a change that still has pending
23 tasks.
24 Usage: snap [OPTIONS] abort [abort-OPTIONS]
26 --last Select last change of given type (install, refresh, remove, try,
28 auto-refresh, etc.). A question mark at the end of the type
29 means to do nothing (instead of returning an error) if no change
30 of the given type is found. Note the question mark could need
31 protecting from the shell.
32 ack
34 Add an assertion to the system
35 The ack command tries to add an assertion to the system assertion data‐
37 base.
38 The assertion may also be a newer revision of a pre-existing assertion
40 that it will replace.
41 To succeed the assertion must be valid, its signature verified with a
43 known public key and the assertion consistent with and its prerequisite
44 in the database.
45 alias
47 Set up a manual alias
48 The alias command aliases the given snap application to the given
50 alias.
51 Once this manual alias is setup the respective application command can
53 be invoked just using the alias.
54 Usage: snap [OPTIONS] alias [alias-OPTIONS]
56 --no-wait
58 Do not wait for the operation to finish but just print the
59 change id.
60 aliases
62 List aliases in the system
63 The aliases command lists all aliases available in the system and their
65 status.
66 $ snap aliases <snap>
68 Lists only the aliases defined by the specified snap.
70 An alias noted as undefined means it was explicitly enabled or disabled
72 but is not defined in the current revision of the snap, possibly tempo‐
73 rarily (e.g. because of a revert). This can cleared with 'snap alias
74 --reset'.
75 changes
77 List system changes
78 The changes command displays a summary of system changes performed
80 recently.
81 Usage: snap [OPTIONS] changes [changes-OPTIONS]
83 --abs-time
85 Display absolute times (in RFC 3339 format). Otherwise, display
86 relative times up to 60 days, then YYYY-MM-DD.
87 check-snapshot
89 Check a snapshot
90 The check-snapshot command verifies the user, system and configuration
92 data of the snaps included in the specified snapshot.
93 The check operation runs the same data integrity verification that is
95 performed when a snapshot is restored.
96 By default, this command checks all the data in a snapshot. Alterna‐
98 tively, you can specify the data of which snaps to check, or for which
99 users, or a combination of these.
100 If a snap is included in a check-snapshot operation, excluding its sys‐
102 tem and configuration data from the check is not currently possible.
103 This restriction may be lifted in the future.
104 Usage: snap [OPTIONS] check-snapshot [check-snapshot-OPTIONS]
106 --no-wait
108 Do not wait for the operation to finish but just print the
109 change id.
110 --users
112 Check data of only specific users (comma-separated) (default:
113 all users)
114 connect
116 Connect a plug to a slot
117 The connect command connects a plug to a slot. It may be called in the
119 following ways:
120 $ snap connect <snap>:<plug> <snap>:<slot>
122 Connects the provided plug to the given slot.
124 $ snap connect <snap>:<plug> <snap>
126 Connects the specific plug to the only slot in the provided snap that
128 matches the connected interface. If more than one potential slot
129 exists, the command fails.
130 $ snap connect <snap>:<plug>
132 Connects the provided plug to the slot in the core snap with a name
134 matching the plug name.
135 Usage: snap [OPTIONS] connect [connect-OPTIONS]
137 --no-wait
139 Do not wait for the operation to finish but just print the
140 change id.
141 connections
143 List interface connections
144 The connections command lists connections between plugs and slots in
146 the system.
147 Unless <snap> is provided, the listing is for connected plugs and slots
149 for all snaps in the system. In this mode, pass --all to also list
150 unconnected plugs and slots.
151 $ snap connections <snap>
153 Lists connected and unconnected plugs and slots for the specified snap.
155 Usage: snap [OPTIONS] connections [connections-OPTIONS]
157 --all Show connected and unconnected plugs and slots
159 disable
161 Disable a snap in the system
162 The disable command disables a snap. The binaries and services of the
164 snap will no longer be available, but all the data is still available
165 and the snap can easily be enabled again.
166 Usage: snap [OPTIONS] disable [disable-OPTIONS]
168 --no-wait
170 Do not wait for the operation to finish but just print the
171 change id.
172 disconnect
174 Disconnect a plug from a slot
175 The disconnect command disconnects a plug from a slot. It may be
177 called in the following ways:
178 $ snap disconnect <snap>:<plug> <snap>:<slot>
180 Disconnects the specific plug from the specific slot.
182 $ snap disconnect <snap>:<slot or plug>
184 Disconnects everything from the provided plug or slot. The snap name
186 may be omitted for the core snap.
187 Usage: snap [OPTIONS] disconnect [disconnect-OPTIONS]
189 --no-wait
191 Do not wait for the operation to finish but just print the
192 change id.
193 download
195 Download the given snap
196 The download command downloads the given snap and its supporting asser‐
198 tions to the current directory with .snap and .assert file extensions,
199 respectively.
200 Usage: snap [OPTIONS] download [download-OPTIONS]
202 --channel
204 Use this channel instead of stable
205 --edge Install from the edge channel
207 --beta Install from the beta channel
209 --candidate
211 Install from the candidate channel
212 --stable
214 Install from the stable channel
215 --revision
217 Download the given revision of a snap, to which you must have
218 developer access
219 enable
221 Enable a snap in the system
222 The enable command enables a snap that was previously disabled.
224 Usage: snap [OPTIONS] enable [enable-OPTIONS]
226 --no-wait
228 Do not wait for the operation to finish but just print the
229 change id.
230 find
232 Find packages to install
233 The find command queries the store for available packages in the stable
235 channel.
236 With the --private flag, which requires the user to be logged-in to the
238 store (see 'snap help login'), it instead searches for private snaps
239 that the user has developer access to, either directly or through the
240 store's collaboration feature.
241 A green check mark (given color and unicode support) after a publisher
243 name indicates that the publisher has been verified.
244 Usage: snap [OPTIONS] find [find-OPTIONS]
246 Aliases: search
249 --private
252 Search private snaps
253 --narrow
255 Only search for snaps in “stable”
256 --section [="show-all-sections-please"] <default: "no-section-speci‐
258 fied">
259 Restrict the search to a given section
260 --color <default: "auto">
262 Use a little bit of color to highlight some things.
263 --unicode <default: "auto">
265 Use a little bit of Unicode to improve legibility.
266 forget
268 Delete a snapshot
269 The forget command deletes a snapshot. This operation can not be
271 undone.
272 A snapshot contains archives for the user, system and configuration
274 data of each snap included in the snapshot.
275 By default, this command forgets all the data in a snapshot. Alterna‐
277 tively, you can specify the data of which snaps to forget.
278 Usage: snap [OPTIONS] forget [forget-OPTIONS]
280 --no-wait
282 Do not wait for the operation to finish but just print the
283 change id.
284 get
286 Print configuration options
287 The get command prints configuration options for the provided snap.
289 $ snap get snap-name username
291 frank
292 If multiple option names are provided, a document is returned:
294 $ snap get snap-name username password
296 {
297 "username": "frank",
298 "password": "..."
299 }
300 Nested values may be retrieved via a dotted path:
302 $ snap get snap-name author.name
304 frank
305 Usage: snap [OPTIONS] get [get-OPTIONS]
307 -t Strict typing with nulls and quoted strings
309 -d Always return document, even with single key
311 -l Always return list, even with single key
313 help
315 Show help about a command
316 The help command displays information about snap commands.
318 Usage: snap [OPTIONS] help [help-OPTIONS]
320 --all Show a short summary of all commands
322 info
324 Show detailed information about snaps
325 The info command shows detailed information about snaps.
327 The snaps can be specified by name or by path; names are looked for
329 both in the store and in the installed snaps; paths can refer to a
330 .snap file, or to a directory that contains an unpacked snap suitable
331 for 'snap try' (an example of this would be the 'prime' directory
332 snapcraft produces).
333 Usage: snap [OPTIONS] info [info-OPTIONS]
335 --color <default: "auto">
337 Use a little bit of color to highlight some things.
338 --unicode <default: "auto">
340 Use a little bit of Unicode to improve legibility.
341 --abs-time
343 Display absolute times (in RFC 3339 format). Otherwise, display
344 relative times up to 60 days, then YYYY-MM-DD.
345 --verbose
347 Include more details on the snap (expanded notes, base, etc.)
348 install
350 Install snaps on the system
351 The install command installs the named snaps on the system.
353 To install multiple instances of the same snap, append an underscore
355 and a unique identifier (for each instance) to a snap's name.
356 With no further options, the snaps are installed tracking the stable
358 channel, with strict security confinement.
359 Revision choice via the --revision override requires the the user to
361 have developer access to the snap, either directly or through the
362 store's collaboration feature, and to be logged in (see 'snap help
363 login').
364 Note a later refresh will typically undo a revision override, taking
366 the snap back to the current revision of the channel it's tracking.
367 Use --name to set the instance name when installing from snap file.
369 Usage: snap [OPTIONS] install [install-OPTIONS]
371 --color <default: "auto">
373 Use a little bit of color to highlight some things.
374 --unicode <default: "auto">
376 Use a little bit of Unicode to improve legibility.
377 --no-wait
379 Do not wait for the operation to finish but just print the
380 change id.
381 --channel
383 Use this channel instead of stable
384 --edge Install from the edge channel
386 --beta Install from the beta channel
388 --candidate
390 Install from the candidate channel
391 --stable
393 Install from the stable channel
394 --devmode
396 Put snap in development mode and disable security confinement
397 --jailmode
399 Put snap in enforced confinement mode
400 --classic
402 Put snap in classic mode and disable security confinement
403 --revision
405 Install the given revision of a snap, to which you must have
406 developer access
407 --dangerous
409 Install the given snap file even if there are no pre-acknowl‐
410 edged signatures for it, meaning it was not verified and could
411 be dangerous (--devmode implies this)
412 --unaliased
414 Install the given snap without enabling its automatic aliases
415 --name Install the snap file under the given instance name
417 interface
419 Show details of snap interfaces
420 The interface command shows details of snap interfaces.
422 If no interface name is provided, a list of interface names with at
424 least one connection is shown, or a list of all interfaces if --all is
425 provided.
426 Usage: snap [OPTIONS] interface [interface-OPTIONS]
428 --attrs
430 Show interface attributes
431 --all Include unused interfaces
433 known
435 Show known assertions of the provided type
436 The known command shows known assertions of the provided type. If
438 header=value pairs are provided after the assertion type, the asser‐
439 tions shown must also have the specified headers matching the provided
440 values.
441 Usage: snap [OPTIONS] known [known-OPTIONS]
443 --remote
445 list
447 List installed snaps
448 The list command displays a summary of snaps installed in the current
450 system.
451 A green check mark (given color and unicode support) after a publisher
453 name indicates that the publisher has been verified.
454 Usage: snap [OPTIONS] list [list-OPTIONS]
456 --all Show all revisions
458 --color <default: "auto">
460 Use a little bit of color to highlight some things.
461 --unicode <default: "auto">
463 Use a little bit of Unicode to improve legibility.
464 login
466 Authenticate to snapd and the store
467 The login command authenticates the user to snapd and the snap store,
469 and saves credentials into the ~/.snap/auth.json file. Further communi‐
470 cation with snapd will then be made using those credentials.
471 It's not necessary to log in to interact with snapd. Doing so, however,
473 enables purchasing of snaps using 'snap buy', as well as some some
474 developer-oriented features as detailed in the help for the find,
475 install and refresh commands.
476 An account can be set up at https://login.ubuntu.com
478 logout
480 Log out of snapd and the store
481 The logout command logs the current user out of snapd and the store.
483 logs
485 Retrieve logs for services
486 The logs command fetches logs of the given services and displays them
488 in chronological order.
489 Usage: snap [OPTIONS] logs [logs-OPTIONS]
491 -n <default: "10">
493 Show only the given number of lines, or 'all'.
494 -f Wait for new lines and print them as they come in.
496 okay
498 Acknowledge warnings
499 The okay command acknowledges the warnings listed with 'snap warnings'.
501 Once acknowledged a warning won't appear again unless it re-occurrs and
503 sufficient time has passed.
504 pack
506 Pack the given directory as a snap
507 The pack command packs the given snap-dir as a snap and writes the
509 result to target-dir. If target-dir is omitted, the result is written
510 to current directory. If both source-dir and target-dir are omitted,
511 the pack command packs the current directory.
512 The default file name for a snap can be derived entirely from its
514 snap.yaml, but in some situations it's simpler for a script to feed the
515 filename in. In those cases, --filename can be given to override the
516 default. If this filename is not absolute it will be taken as relative
517 to target-dir.
518 When used with --check-skeleton, pack only checks whether snap-dir con‐
520 tains valid snap metadata and raises an error otherwise. Application
521 commands listed in snap metadata file, but appearing with incorrect
522 permission bits result in an error. Commands that are missing from
523 snap-dir are listed in diagnostic messages.
524 Usage: snap [OPTIONS] pack [pack-OPTIONS]
526 --check-skeleton
528 Validate snap-dir metadata only
529 --filename
531 Output to this filename
532 prefer
534 Enable aliases from a snap, disabling any conflicting aliases
535 The prefer command enables all aliases of the given snap in preference
537 to conflicting aliases of other snaps whose aliases will be disabled
538 (or removed, for manual ones).
539 Usage: snap [OPTIONS] prefer [prefer-OPTIONS]
541 --no-wait
543 Do not wait for the operation to finish but just print the
544 change id.
545 prepare-image
547 Prepare a device image
548 The prepare-image command performs some of the steps necessary for cre‐
550 ating device images.
551 For core images it is not invoked directly but usually via ubuntu-
553 image.
554 For preparing classic images it supports a --classic mode
556 Usage: snap [OPTIONS] prepare-image [prepare-image-OPTIONS]
558 --classic
560 Enable classic mode to prepare a classic model image
561 --arch Specify an architecture for snaps for --classic when the model
563 does not
564 --channel <default: "stable">
566 The channel to use
567 --snap <snap>[=<channel>]
569 Include the given snap from the store or a local file and/or
570 specify the channel to track for the given snap
571 refresh
573 Refresh snaps in the system
574 The refresh command updates the specified snaps, or all snaps in the
576 system if none are specified.
577 With no further options, the snaps are refreshed to the current revi‐
579 sion of the channel they're tracking, preserving their confinement
580 options.
581 Revision choice via the --revision override requires the the user to
583 have developer access to the snap, either directly or through the
584 store's collaboration feature, and to be logged in (see 'snap help
585 login').
586 Note a later refresh will typically undo a revision override.
588 Usage: snap [OPTIONS] refresh [refresh-OPTIONS]
590 --color <default: "auto">
592 Use a little bit of color to highlight some things.
593 --unicode <default: "auto">
595 Use a little bit of Unicode to improve legibility.
596 --abs-time
598 Display absolute times (in RFC 3339 format). Otherwise, display
599 relative times up to 60 days, then YYYY-MM-DD.
600 --no-wait
602 Do not wait for the operation to finish but just print the
603 change id.
604 --channel
606 Use this channel instead of stable
607 --edge Install from the edge channel
609 --beta Install from the beta channel
611 --candidate
613 Install from the candidate channel
614 --stable
616 Install from the stable channel
617 --devmode
619 Put snap in development mode and disable security confinement
620 --jailmode
622 Put snap in enforced confinement mode
623 --classic
625 Put snap in classic mode and disable security confinement
626 --amend
628 Allow refresh attempt on snap unknown to the store
629 --revision
631 Refresh to the given revision, to which you must have developer
632 access
633 --list Show the new versions of snaps that would be updated with the
635 next refresh
636 --time Show auto refresh information but do not perform a refresh
638 --ignore-validation
640 Ignore validation by other snaps blocking the refresh
641 remove
643 Remove snaps from the system
644 The remove command removes the named snap instance from the system.
646 By default all the snap revisions are removed, including their data and
648 the common data directory. When a --revision option is passed only the
649 specified revision is removed.
650 Usage: snap [OPTIONS] remove [remove-OPTIONS]
652 --no-wait
654 Do not wait for the operation to finish but just print the
655 change id.
656 --revision
658 Remove only the given revision
659 restart
661 Restart services
662 The restart command restarts the given services.
664 If the --reload option is given, for each service whose app has a
666 reload command, a reload is performed instead of a restart.
667 Usage: snap [OPTIONS] restart [restart-OPTIONS]
669 --no-wait
671 Do not wait for the operation to finish but just print the
672 change id.
673 --reload
675 If the service has a reload command, use it instead of restart‐
676 ing.
677 restore
679 Restore a snapshot
680 The restore command replaces the current user, system and configuration
682 data of included snaps, with the corresponding data from the specified
683 snapshot.
684 By default, this command restores all the data in a snapshot. Alterna‐
686 tively, you can specify the data of which snaps to restore, or for
687 which users, or a combination of these.
688 If a snap is included in a restore operation, excluding its system and
690 configuration data from the restore is not currently possible. This
691 restriction may be lifted in the future.
692 Usage: snap [OPTIONS] restore [restore-OPTIONS]
694 --no-wait
696 Do not wait for the operation to finish but just print the
697 change id.
698 --users
700 Restore data of only specific users (comma-separated) (default:
701 all users)
702 revert
704 Reverts the given snap to the previous state
705 The revert command reverts the given snap to its state before the lat‐
707 est refresh. This will reactivate the previous snap revision, and will
708 use the original data that was associated with that revision, discard‐
709 ing any data changes that were done by the latest revision. As an
710 exception, data which the snap explicitly chooses to share across revi‐
711 sions is not touched by the revert process.
712 Usage: snap [OPTIONS] revert [revert-OPTIONS]
714 --no-wait
716 Do not wait for the operation to finish but just print the
717 change id.
718 --devmode
720 Put snap in development mode and disable security confinement
721 --jailmode
723 Put snap in enforced confinement mode
724 --classic
726 Put snap in classic mode and disable security confinement
727 --revision
729 Revert to the given revision
730 run
732 Run the given snap command
733 The run command executes the given snap command with the right confine‐
735 ment and environment.
736 Usage: snap [OPTIONS] run [run-OPTIONS]
738 --shell
740 Run a shell instead of the command (useful for debugging)
741 --strace [="with-strace"] <default: "no-strace">
743 Run the command under strace (useful for debugging). Extra
744 strace options can be specified as well here. Pass --raw to
745 strace early snap helpers.
746 --gdb Run the command with gdb
748 --trace-exec
750 Display exec calls timing data
751 save
753 Save a snapshot of the current data
754 The save command creates a snapshot of the current user, system and
756 configuration data for the given snaps.
757 By default, this command saves the data of all snaps for all users.
759 Alternatively, you can specify the data of which snaps to save, or for
760 which users, or a combination of these.
761 If a snap is included in a save operation, excluding its system and
763 configuration data from the snapshot is not currently possible. This
764 restriction may be lifted in the future.
765 Usage: snap [OPTIONS] save [save-OPTIONS]
767 --no-wait
769 Do not wait for the operation to finish but just print the
770 change id.
771 --abs-time
773 Display absolute times (in RFC 3339 format). Otherwise, display
774 short relative times.
775 --users
777 Snapshot data of only specific users (comma-separated) (default:
778 all users)
779 saved
781 List currently stored snapshots
782 The saved command displays a list of snapshots that have been created
784 previously with the 'save' command.
785 Usage: snap [OPTIONS] saved [saved-OPTIONS]
787 --abs-time
789 Display absolute times (in RFC 3339 format). Otherwise, display
790 short relative times.
791 --id Show only a specific snapshot.
793 services
795 Query the status of services
796 The services command lists information about the services specified, or
798 about the services in all currently installed snaps.
799 set
801 Change configuration options
802 The set command changes the provided configuration options as
804 requested.
805 $ snap set snap-name username=frank password=$PASSWORD
807 All configuration changes are persisted at once, and only after the
809 snap's configuration hook returns successfully.
810 Nested values may be modified via a dotted path:
812 $ snap set author.name=frank
814 Usage: snap [OPTIONS] set [set-OPTIONS]
816 --no-wait
818 Do not wait for the operation to finish but just print the
819 change id.
820 start
822 Start services
823 The start command starts, and optionally enables, the given services.
825 Usage: snap [OPTIONS] start [start-OPTIONS]
827 --no-wait
829 Do not wait for the operation to finish but just print the
830 change id.
831 --enable
833 As well as starting the service now, arrange for it to be
834 started on boot.
835 stop
837 Stop services
838 The stop command stops, and optionally disables, the given services.
840 Usage: snap [OPTIONS] stop [stop-OPTIONS]
842 --no-wait
844 Do not wait for the operation to finish but just print the
845 change id.
846 --disable
848 As well as stopping the service now, arrange for it to no longer
849 be started on boot.
850 switch
852 Switches snap to a different channel
853 The switch command switches the given snap to a different channel with‐
855 out doing a refresh.
856 Usage: snap [OPTIONS] switch [switch-OPTIONS]
858 --no-wait
860 Do not wait for the operation to finish but just print the
861 change id.
862 --channel
864 Use this channel instead of stable
865 --edge Install from the edge channel
867 --beta Install from the beta channel
869 --candidate
871 Install from the candidate channel
872 --stable
874 Install from the stable channel
875 tasks
877 List a change's tasks
878 The tasks command displays a summary of tasks associated with an indi‐
880 vidual change.
881 Usage: snap [OPTIONS] tasks [tasks-OPTIONS]
883 Aliases: change
886 --abs-time
889 Display absolute times (in RFC 3339 format). Otherwise, display
890 relative times up to 60 days, then YYYY-MM-DD.
891 --last Select last change of given type (install, refresh, remove, try,
893 auto-refresh, etc.). A question mark at the end of the type
894 means to do nothing (instead of returning an error) if no change
895 of the given type is found. Note the question mark could need
896 protecting from the shell.
897 try
899 Test an unpacked snap in the system
900 The try command installs an unpacked snap into the system for testing
902 purposes. The unpacked snap content continues to be used even after
903 installation, so non-metadata changes there go live instantly. Metadata
904 changes such as those performed in snap.yaml will require reinstalla‐
905 tion to go live.
906 If snap-dir argument is omitted, the try command will attempt to infer
908 it if either snapcraft.yaml file and prime directory or meta/snap.yaml
909 file can be found relative to current working directory.
910 Usage: snap [OPTIONS] try [try-OPTIONS]
912 --no-wait
914 Do not wait for the operation to finish but just print the
915 change id.
916 --devmode
918 Put snap in development mode and disable security confinement
919 --jailmode
921 Put snap in enforced confinement mode
922 --classic
924 Put snap in classic mode and disable security confinement
925 unalias
927 Remove a manual alias, or the aliases for an entire snap
928 The unalias command removes a single alias if the provided argument is
930 a manual alias, or disables all aliases of a snap, including manual
931 ones, if the argument is a snap name.
932 Usage: snap [OPTIONS] unalias [unalias-OPTIONS]
934 --no-wait
936 Do not wait for the operation to finish but just print the
937 change id.
938 version
940 Show version details
941 The version command displays the versions of the running client,
943 server, and operating system.
944 wait
946 Wait for configuration
947 The wait command waits until a configuration becomes true.
949 warnings
951 List warnings
952 The warnings command lists the warnings that have been reported to the
954 system.
955 Once warnings have been listed with 'snap warnings', 'snap okay' may be
957 used to silence them. A warning that's been silenced in this way will
958 not be listed again unless it happens again, _and_ a cooldown time has
959 passed.
960 Warnings expire automatically, and once expired they are forgotten.
962 Usage: snap [OPTIONS] warnings [warnings-OPTIONS]
964 --abs-time
966 Display absolute times (in RFC 3339 format). Otherwise, display
967 relative times up to 60 days, then YYYY-MM-DD.
968 --unicode <default: "auto">
970 Use a little bit of Unicode to improve legibility.
971 --all Show all warnings
973 --verbose
975 Show more information
976 watch
978 Watch a change in progress
979 The watch command waits for the given change-id to finish and shows
981 progress (if available).
982 Usage: snap [OPTIONS] watch [watch-OPTIONS]
984 --last Select last change of given type (install, refresh, remove, try,
986 auto-refresh, etc.). A question mark at the end of the type
987 means to do nothing (instead of returning an error) if no change
988 of the given type is found. Note the question mark could need
989 protecting from the shell.
990 whoami
992 Show the email the user is logged in with
993 The whoami command shows the email the user is logged in with.
995 4 June 2019 snap(8)