restic/doc/manual_rest.rst

Manual
======

Usage help
----------

Usage help is available:

.. code-block:: console

    $ ./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:

.. code-block:: console

    $ ./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 SIGUSR 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:

.. code-block:: console

    $ 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:

.. code-block:: console

    $ 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 <https://github.com/restic/restic/blob/master/doc/Design.rst>`__.
You can ``list`` objects such as blobs, packs, index, snapshots, keys or
locks with the following command:

.. code-block:: console

    $ restic -r /tmp/backup list snapshots
    d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c

The ``find`` command searches for a given
`pattern <http://golang.org/pkg/path/filepath/#Match>`__ in the
repository.

.. code-block:: console

    $ 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.

.. code-block:: console

    $ 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 <https://stedolan.github.io/jq/>`__). The following example
lists all snapshots as JSON and uses ``jq`` to pretty-print the result:

.. code-block:: console

    $ 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:

.. code-block:: console

    $ 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 the
directory ``.cache/restic`` in the user's home directory. The environment
variable ``XDG_CACHE_DIR`` or the command line parameter ``--cache-dir`` can
each be used to specify where the cache is located. 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.