Working with repositories

Listing all snapshots

Now, you can list all the snapshots stored in the repository:

$ restic -r /srv/restic-repo snapshots
enter password for repository:
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
40dc1520  2015-05-08 21:38:30  kasimir        /home/user/work
79766175  2015-05-08 21:40:19  kasimir        /home/user/work
bdbd3439  2015-05-08 21:45:17  luigi          /home/art
590c8fc8  2015-05-08 21:47:38  kazik          /srv
9f0bc19e  2015-05-08 21:46:11  luigi          /srv

You can filter the listing by directory path:

$ restic -r /srv/restic-repo snapshots --path="/srv"
enter password for repository:
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
590c8fc8  2015-05-08 21:47:38  kazik          /srv
9f0bc19e  2015-05-08 21:46:11  luigi          /srv

Or filter by host:

$ restic -r /srv/restic-repo snapshots --host luigi
enter password for repository:
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
bdbd3439  2015-05-08 21:45:17  luigi          /home/art
9f0bc19e  2015-05-08 21:46:11  luigi          /srv

Combining filters is also possible.

Furthermore you can group the output by the same filters (host, paths, tags):

$ restic -r /srv/restic-repo snapshots --group-by host

enter password for repository:
snapshots for (host [kasimir])
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
40dc1520  2015-05-08 21:38:30  kasimir        /home/user/work
79766175  2015-05-08 21:40:19  kasimir        /home/user/work
2 snapshots
snapshots for (host [luigi])
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
bdbd3439  2015-05-08 21:45:17  luigi          /home/art
9f0bc19e  2015-05-08 21:46:11  luigi          /srv
2 snapshots
snapshots for (host [kazik])
ID        Date                 Host    Tags   Directory
----------------------------------------------------------------------
590c8fc8  2015-05-08 21:47:38  kazik          /srv
1 snapshots

Listing files in a snapshot

To get a list of the files in a specific snapshot you can use the ls command:

$ restic ls 073a90db

snapshot 073a90db of [/home/user/work.txt] filtered by [] at 2024-01-21 16:51:18.474558607 +0100 CET):
/home
/home/user
/home/user/work.txt

The special snapshot ID latest can be used to list files and directories of the latest snapshot in the repository. The --host flag can be used in conjunction to select the latest snapshot originating from a certain host only.

$ restic ls --host kasimir latest

snapshot 073a90db of [/home/user/work.txt] filtered by [] at 2024-01-21 16:51:18.474558607 +0100 CET):
/home
/home/user
/home/user/work.txt

By default, ls prints all files in a snapshot.

File listings can optionally be filtered by directories. Any positional arguments after the snapshot ID are interpreted as absolute directory paths, and only files inside those directories will be listed. Files in subdirectories are not listed when filtering by directories. If the --recursive flag is used, then subdirectories are also included. Any directory paths specified must be absolute (starting with a path separator); paths use the forward slash ‘/’ as separator.

$ restic ls latest /home

snapshot 073a90db of [/home/user/work.txt] filtered by [/home] at 2024-01-21 16:51:18.474558607 +0100 CET):
/home
/home/user
$ restic ls --recursive latest /home

snapshot 073a90db of [/home/user/work.txt] filtered by [/home] at 2024-01-21 16:51:18.474558607 +0100 CET):
/home
/home/user
/home/user/work.txt

To show more details about the files in a snapshot, you can use the --long option. The colums include file permissions, UID, GID, file size, modification time and file path. For scripting usage, the ls command supports the --json flag; the JSON output format is described at ls.

$ restic ls --long latest

snapshot 073a90db of [/home/user/work.txt] filtered by [] at 2024-01-21 16:51:18.474558607 +0100 CET):
drwxr-xr-x     0     0      0 2024-01-21 16:50:52 /home
drwxr-xr-x     0     0      0 2024-01-21 16:51:03 /home/user
-rw-r--r--     0     0     18 2024-01-21 16:51:03 /home/user/work.txt

NCDU (NCurses Disk Usage) is a tool to analyse disk usage of directories. The ls command supports outputting information about a snapshot in the NCDU format using the --ncdu option.

You can use it as follows: restic ls latest --ncdu | ncdu -f -

Copying snapshots between repositories

In case you want to transfer snapshots between two repositories, for example from a local to a remote repository, you can use the copy command:

$ restic -r /srv/restic-repo-copy copy --from-repo /srv/restic-repo
repository d6504c63 opened successfully, password is correct
repository 3dd0878c opened successfully, password is correct

snapshot 410b18a2 of [/home/user/work] at 2020-06-09 23:15:57.305305 +0200 CEST by user@kasimir
  copy started, this may take a while...
snapshot 7a746a07 saved

snapshot 4e5d5487 of [/home/user/work] at 2020-05-01 22:44:07.012113 +0200 CEST by user@kasimir
skipping snapshot 4e5d5487, was already copied to snapshot 50eb62b7

The example command copies all snapshots from the source repository /srv/restic-repo to the destination repository /srv/restic-repo-copy. Snapshots which have previously been copied between repositories will be skipped by later copy runs.

Important

This process will have to both download (read) and upload (write) the entire snapshot(s) due to the different encryption keys used in the source and destination repository. This may incur higher bandwidth usage and costs than expected during normal backup runs.

Important

The copying process does not re-chunk files, which may break deduplication between the files copied and files already stored in the destination repository. This means that copied files, which existed in both the source and destination repository, may occupy up to twice their space in the destination repository. See below for how to avoid this.

The source repository is specified with --from-repo or can be read from a file specified via --from-repository-file. Both of these options can also be set as environment variables $RESTIC_FROM_REPOSITORY or $RESTIC_FROM_REPOSITORY_FILE, respectively. For the source repository the password can be read from a file --from-password-file or from a command --from-password-command. Alternatively the environment variables $RESTIC_FROM_PASSWORD_COMMAND and $RESTIC_FROM_PASSWORD_FILE can be used. It is also possible to directly pass the password via $RESTIC_FROM_PASSWORD. The key which should be used for decryption can be selected by passing its ID via the flag --from-key-hint or the environment variable $RESTIC_FROM_KEY_HINT.

Note

In case the source and destination repository use the same backend, the configuration options and environment variables used to configure the backend may apply to both repositories – for example it might not be possible to specify different accounts for the source and destination repository. You can avoid this limitation by using the rclone backend along with remotes which are configured in rclone.

Note

If copy is aborted, copy will resume the interrupted copying when it is run again. It’s possible that up to 10 minutes of progress can be lost because the repository index is only updated from time to time.

Filtering snapshots to copy

The list of snapshots to copy can be filtered by host, path in the backup and/or a comma-separated tag list:

$ restic -r /srv/restic-repo-copy copy --from-repo /srv/restic-repo --host luigi --path /srv --tag foo,bar

It is also possible to explicitly specify the list of snapshots to copy, in which case only these instead of all snapshots will be copied:

$ restic -r /srv/restic-repo-copy copy --from-repo /srv/restic-repo 410b18a2 4e5d5487 latest

Ensuring deduplication for copied snapshots

Even though the copy command can transfer snapshots between arbitrary repositories, deduplication between snapshots from the source and destination repository may not work. To ensure proper deduplication, both repositories have to use the same parameters for splitting large files into smaller chunks, which requires additional setup steps. With the same parameters restic will for both repositories split identical files into identical chunks and therefore deduplication also works for snapshots copied between these repositories.

The chunker parameters are generated once when creating a new (destination) repository. That is for a copy destination repository we have to instruct restic to initialize it using the same chunker parameters as the source repository:

$ restic -r /srv/restic-repo-copy init --from-repo /srv/restic-repo --copy-chunker-params

Note that it is not possible to change the chunker parameters of an existing repository.

Removing files from snapshots

Snapshots sometimes turn out to include more files that intended. Instead of removing the snapshots entirely and running the corresponding backup commands again (which is not always practical after the fact) it is possible to remove the unwanted files from affected snapshots by rewriting them using the rewrite command:

$ restic -r /srv/restic-repo rewrite --exclude secret-file
repository c881945a opened (repository version 2) successfully, password is correct

snapshot 6160ddb2 of [/home/user/work] at 2022-06-12 16:01:28.406630608 +0200 CEST by user@kasimir
excluding /home/user/work/secret-file
saved new snapshot b6aee1ff

snapshot 4fbaf325 of [/home/user/work] at 2022-05-01 11:22:26.500093107 +0200 CEST by user@kasimir

modified 1 snapshots

$ restic -r /srv/restic-repo rewrite --exclude secret-file 6160ddb2
repository c881945a opened (repository version 2) successfully, password is correct

snapshot 6160ddb2 of [/home/user/work] at 2022-06-12 16:01:28.406630608 +0200 CEST by user@kasimir
excluding /home/user/work/secret-file
new snapshot saved as b6aee1ff

modified 1 snapshots

The options --exclude, --exclude-file, --iexclude and --iexclude-file are supported. They behave the same way as for the backup command, see Excluding Files for details.

It is possible to rewrite only a subset of snapshots by filtering them the same way as for the copy command, see Filtering snapshots to copy.

By default, the rewrite command will keep the original snapshots and create new ones for every snapshot which was modified during rewriting. The new snapshots are marked with the tag rewrite to differentiate them from the original, rewritten snapshots.

Alternatively, you can use the --forget option to immediately remove the original snapshots. In this case, no tag is added to the new snapshots. Please note that this only removes the snapshots and not the actual data stored in the repository. Run the prune command afterwards to remove the now unreferenced data (just like when having used the forget command).

In order to preview the changes which rewrite would make, you can use the --dry-run option. This will simulate the rewriting process without actually modifying the repository. Instead restic will only print the actions it would perform.

Modifying metadata of snapshots

Sometimes it may be desirable to change the metadata of an existing snapshot. Currently, rewriting the hostname and the time of the backup is supported. This is possible using the rewrite command with the option --new-host followed by the desired new hostname or the option --new-time followed by the desired new timestamp.

$ restic rewrite --new-host newhost --new-time "1999-01-01 11:11:11"

repository b7dbade3 opened (version 2, compression level auto)
[0:00] 100.00%  1 / 1 index files loaded

snapshot 8ed674f4 of [/path/to/abc.txt] at 2023-11-27 21:57:52.439139291 +0100 CET by user@kasimir
setting time to 1999-01-01 11:11:11 +0100 CET
setting host to newhost
saved new snapshot c05da643

modified 1 snapshots

Checking integrity and consistency

Imagine your repository is saved on a server that has a faulty hard drive, or even worse, attackers get privileged access and modify the files in your repository with the intention to make you restore malicious data:

$ echo "boom" > /srv/restic-repo/index/de30f3231ca2e6a59af4aa84216dfe2ef7339c549dc11b09b84000997b139628

Trying to restore a snapshot which has been modified as shown above will yield an error:

$ restic -r /srv/restic-repo --no-cache restore c23e491f --target /tmp/restore-work
...
Fatal: unable to load index de30f323: load <index/de30f3231c>: invalid data returned

In order to detect these things before they become a problem, it’s a good idea to regularly use the check command to test whether your repository is healthy and consistent, and that your precious backup data is unharmed. There are two types of checks that can be performed:

  • Structural consistency and integrity, e.g. snapshots, trees and pack files (default)

  • Integrity of the actual data that you backed up (enabled with flags, see below)

To verify the structure of the repository, issue the check command. If the repository is damaged like in the example above, check will detect this and yield the same error as when you tried to restore:

$ restic -r /srv/restic-repo check
...
load indexes
error: error loading index de30f323: load <index/de30f3231c>: invalid data returned
Fatal: LoadIndex returned errors

If the repository structure is intact, restic will show that no errors were found:

$ restic -r /src/restic-repo check
...
load indexes
check all packs
check snapshots, trees and blobs
no errors were found

By default, check creates a new temporary cache directory to verify that the data stored in the repository is intact. To reuse the existing cache, you can use the --with-cache flag.

If the cache directory is not explicitly set, then check creates its temporary cache directory in the temporary directory, see Temporary files. Otherwise, the specified cache directory is used, as described in Caching.

By default, the check command does not verify that the actual pack files on disk in the repository are unmodified, because doing so requires reading a copy of every pack file in the repository. To tell restic to also verify the integrity of the pack files in the repository, use the --read-data flag:

$ restic -r /srv/restic-repo check --read-data
...
load indexes
check all packs
check snapshots, trees and blobs
read all data
[0:00] 100.00%  3 / 3 items
duration: 0:00
no errors were found

Note

Since --read-data has to download all pack files in the repository, beware that it might incur higher bandwidth costs than usual and also that it takes more time than the default check.

Alternatively, use the --read-data-subset parameter to check only a subset of the repository pack files at a time. It supports three ways to select a subset. One selects a specific part of pack files, the second and third selects a random subset of the pack files by the given percentage or size.

Use --read-data-subset=n/t to check a specific part of the repository pack files at a time. The parameter takes two values, n and t. When the check command runs, all pack files in the repository are logically divided in t (roughly equal) groups, and only files that belong to group number n are checked. For example, the following commands check all repository pack files over 5 separate invocations:

$ restic -r /srv/restic-repo check --read-data-subset=1/5
$ restic -r /srv/restic-repo check --read-data-subset=2/5
$ restic -r /srv/restic-repo check --read-data-subset=3/5
$ restic -r /srv/restic-repo check --read-data-subset=4/5
$ restic -r /srv/restic-repo check --read-data-subset=5/5

Use --read-data-subset=x% to check a randomly chosen subset of the repository pack files. It takes one parameter, x, the percentage of pack files to check as an integer or floating point number. This will not guarantee to cover all available pack files after sufficient runs, but it is easy to automate checking a small subset of data after each backup. For a floating point value the following command may be used:

$ restic -r /srv/restic-repo check --read-data-subset=2.5%

When checking bigger subsets you most likely want to specify the percentage as an integer:

$ restic -r /srv/restic-repo check --read-data-subset=10%

Use --read-data-subset=nS to check a randomly chosen subset of the repository pack files. It takes one parameter, nS, where ‘n’ is a whole number representing file size and ‘S’ is the unit of file size (K/M/G/T) of pack files to check. Behind the scenes, the specified size will be converted to percentage of the total repository size. The behaviour of the check command following this conversion will be the same as the percentage option above. For a file size value the following command may be used:

$ restic -r /srv/restic-repo check --read-data-subset=50M
$ restic -r /srv/restic-repo check --read-data-subset=10G

Upgrading the repository format version

Repositories created using earlier restic versions use an older repository format version and have to be upgraded to allow using all new features. Upgrading must be done explicitly as a newer repository version increases the minimum restic version required to access the repository. For example the repository format version 2 is only readable using restic 0.14.0 or newer.

Upgrading to repository version 2 is a two step process: first run migrate upgrade_repo_v2 which will check the repository integrity and then upgrade the repository version. Repository problems must be corrected before the migration will be possible. After the migration is complete, run prune to compress the repository metadata. To limit the amount of data rewritten in at once, you can use the prune --max-repack-size size parameter, see Customize pruning for more details.

File contents stored in the repository will not be rewritten, data from new backups will be compressed. Over time more and more of the repository will be compressed. To speed up this process and compress all not yet compressed data, you can run prune --repack-uncompressed. When you plan to create your backups with maximum compression, you should also add the --compression max flag to the prune command. For already backed up data, the compression level cannot be changed later on.