Manual

Usage help

Usage help is available:

$ ./restic --help
restic is a backup program which allows saving multiple revisions of files and
directories in an encrypted repository stored on different backends.

Usage:
  restic [command]

Available Commands:
  autocomplete  Generate shell autocompletion script
  backup        Create a new backup of files and/or directories
  cat           Print internal objects to stdout
  check         Check the repository for errors
  dump          Dump data structures
  find          Find a file or directory
  forget        Remove snapshots from the repository
  help          Help about any command
  init          Initialize a new repository
  key           Manage keys (passwords)
  list          List items in the repository
  ls            List files in a snapshot
  mount         Mount the repository
  prune         Remove unneeded data from the repository
  rebuild-index Build a new index file
  restore       Extract the data from a snapshot
  snapshots     List all snapshots
  tag           Modify tags on snapshots
  unlock        Remove locks other processes created
  version       Print version information

Flags:
      --json                   set output mode to JSON for commands that support it
      --no-lock                do not lock the repo, this allows some operations on read-only repos
  -p, --password-file string   read the repository password from a file
  -q, --quiet                  do not output comprehensive progress report
  -r, --repo string            repository to backup to or restore from (default: $RESTIC_REPOSITORY)

Use "restic [command] --help" for more information about a command.

Similar to programs such as git, restic has a number of sub-commands. You can see these commands in the listing above. Each sub-command may have own command-line options, and there is a help option for each command which lists them, e.g. for the backup command:

$ ./restic backup --help
The "backup" command creates a new snapshot and saves the files and directories
given as the arguments.

Usage:
  restic backup [flags] FILE/DIR [FILE/DIR] ...

Flags:
  -e, --exclude pattern         exclude a pattern (can be specified multiple times)
      --exclude-file string     read exclude patterns from a file
      --files-from string       read the files to backup from file (can be combined with file args)
  -f, --force                   force re-reading the target files/directories. Overrides the "parent" flag
  -x, --one-file-system         Exclude other file systems
      --parent string           use this parent snapshot (default: last snapshot in the repo that has the same target files/directories)
      --stdin                   read backup from stdin
      --stdin-filename string   file name to use when reading from stdin
      --tag tag                 add a tag for the new snapshot (can be specified multiple times)
      --time string             time of the backup (ex. '2012-11-01 22:08:41') (default: now)

Global Flags:
      --json                   set output mode to JSON for commands that support it
      --no-lock                do not lock the repo, this allows some operations on read-only repos
  -p, --password-file string   read the repository password from a file
  -q, --quiet                  do not output comprehensive progress report
  -r, --repo string            repository to backup to or restore from (default: $RESTIC_REPOSITORY)

Subcommand that support showing progress information such as backup, check and prune will do so unless the quiet flag -q or --quiet is set. When running from a non-interactive console progress reporting will be limited to once every 10 seconds to not fill your logs.

Additionally on Unix systems if restic receives a SIGUSR1 signal the current progress will written to the standard output so you can check up on the status at will.

Manage tags

Managing tags on snapshots is done with the tag command. The existing set of tags can be replaced completely, tags can be added to removed. The result is directly visible in the snapshots command.

Let’s say we want to tag snapshot 590c8fc8 with the tags NL and CH and remove all other tags that may be present, the following command does that:

$ restic -r /tmp/backup tag --set NL --set CH 590c8fc8
create exclusive lock for repository
modified tags on 1 snapshots

Note the snapshot ID has changed, so between each change we need to look up the new ID of the snapshot. But there is an even better way, the tag command accepts --tag for a filter, so we can filter snapshots based on the tag we just added.

So we can add and remove tags incrementally like this:

$ restic -r /tmp/backup tag --tag NL --remove CH
create exclusive lock for repository
modified tags on 1 snapshots

$ restic -r /tmp/backup tag --tag NL --add UK
create exclusive lock for repository
modified tags on 1 snapshots

$ restic -r /tmp/backup tag --tag NL --remove NL
create exclusive lock for repository
modified tags on 1 snapshots

$ restic -r /tmp/backup tag --tag NL --add SOMETHING
no snapshots were modified

Under the hood

Browse repository objects

Internally, a repository stores data of several different types described in the design documentation. You can list objects such as blobs, packs, index, snapshots, keys or locks with the following command:

$ restic -r /tmp/backup list snapshots
d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c

The find command searches for a given pattern in the repository.

$ restic -r backup find test.txt
debug log file restic.log
debug enabled
enter password for repository:
found 1 matching entries in snapshot 196bc5760c909a7681647949e80e5448e276521489558525680acf1bd428af36
  -rw-r--r--   501    20      5 2015-08-26 14:09:57 +0200 CEST path/to/test.txt

The cat command allows you to display the JSON representation of the objects or its raw content.

$ restic -r /tmp/backup cat snapshot d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c
enter password for repository:
{
  "time": "2015-08-12T12:52:44.091448856+02:00",
  "tree": "05cec17e8d3349f402576d02576a2971fc0d9f9776ce2f441c7010849c4ff5af",
  "paths": [
    "/home/user/work"
  ],
  "hostname": "kasimir",
  "username": "username",
  "uid": 501,
  "gid": 20
}

Metadata handling

Restic saves and restores most default attributes, including extended attributes like ACLs. Sparse files are not handled in a special way yet, and aren’t restored.

The following metadata is handled by restic:

  • Name
  • Type
  • Mode
  • ModTime
  • AccessTime
  • ChangeTime
  • UID
  • GID
  • User
  • Group
  • Inode
  • Size
  • Links
  • LinkTarget
  • Device
  • Content
  • Subtree
  • ExtendedAttributes

Scripting

Restic supports the output of some commands in JSON format, the JSON data can then be processed by other programs (e.g. jq). The following example lists all snapshots as JSON and uses jq to pretty-print the result:

$ restic -r /tmp/backup snapshots --json | jq .
[
  {
    "time": "2017-03-11T09:57:43.26630619+01:00",
    "tree": "bf25241679533df554fc0fd0ae6dbb9dcf1859a13f2bc9dd4543c354eff6c464",
    "paths": [
      "/home/work/doc"
    ],
    "hostname": "kasimir",
    "username": "fd0",
    "uid": 1000,
    "gid": 100,
    "id": "bbeed6d28159aa384d1ccc6fa0b540644b1b9599b162d2972acda86b1b80f89e"
  },
  {
    "time": "2017-03-11T09:58:57.541446938+01:00",
    "tree": "7f8c95d3420baaac28dc51609796ae0e0ecfb4862b609a9f38ffaf7ae2d758da",
    "paths": [
      "/home/user/shared"
    ],
    "hostname": "kasimir",
    "username": "fd0",
    "uid": 1000,
    "gid": 100,
    "id": "b157d91c16f0ba56801ece3a708dfc53791fe2a97e827090d6ed9a69a6ebdca0"
  }
]

Temporary files

During some operations (e.g. backup and prune) restic uses temporary files to store data. These files will, by default, be saved to the system’s temporary directory, on Linux this is usually located in /tmp/. The environment variable TMPDIR can be used to specify a different directory, e.g. to use the directory /var/tmp/restic-tmp instead of the default, set the environment variable like this:

$ export TMPDIR=/var/tmp/restic-tmp
$ restic -r /tmp/backup backup ~/work

Caching

Restic keeps a cache with some files from the repository on the local machine. This allows faster operations, since meta data does not need to be loaded from a remote repository. The cache is automatically created, usually in an OS-specific cache folder:

  • Linux/other: ~/.cache/restic (or $XDG_CACHE_HOME/restic)
  • macOS: ~/Library/Caches/restic
  • Windows: %LOCALAPPDATA%/restic

The command line parameter --cache-dir can each be used to override the default cache location. The parameter --no-cache disables the cache entirely. In this case, all data is loaded from the repo.

The cache is ephemeral: When a file cannot be read from the cache, it is loaded from the repository.