restic/doc/manual_rest.rst
Alexander Neumann dc38265b54 Merge pull request from restic/remove-old-cache
Remove old cache directories
2017-11-27 21:37:05 +01:00

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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 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:
.. 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 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.
Within the cache directory, there's a sub directory for each repository the
cache was used with. Restic updates the timestamps of a repo directory each
time it is used, so by looking at the timestamps of the sub directories of the
cache directory it can decide which sub directories are old and probably not
needed any more. You can either remove these directories manually, or run a
restic command with the ``--cleanup-cache`` flag.