restic/doc/manual_rest.rst

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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:
backup Create a new backup of files and/or directories
cache Operate on local cache directories
cat Print internal objects to stdout
check Check the repository for errors
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diff Show differences between two snapshots
dump Print a backed-up file to stdout
find Find a file, a directory or restic IDs
forget Remove snapshots from the repository
generate Generate manual pages and auto-completion files (bash, zsh)
help Help about any command
init Initialize a new repository
key Manage keys (passwords)
list List objects in the repository
ls List files in a snapshot
migrate Apply migrations
mount Mount the repository
prune Remove unneeded data from the repository
rebuild-index Build a new index file
recover Recover data from the repository
restore Extract the data from a snapshot
self-update Update the restic binary
snapshots List all snapshots
stats Scan the repository and show basic statistics
tag Modify tags on snapshots
unlock Remove locks other processes created
version Print version information
Flags:
--cacert file file to load root certificates from (default: use system certificates)
--cache-dir directory set the cache directory. (default: use system default cache directory)
--cleanup-cache auto remove old cache directories
-h, --help help for restic
--json set output mode to JSON for commands that support it
--key-hint key key ID of key to try decrypting first (default: $RESTIC_KEY_HINT)
--limit-download int limits downloads to a maximum rate in KiB/s. (default: unlimited)
--limit-upload int limits uploads to a maximum rate in KiB/s. (default: unlimited)
--no-cache do not use a local cache
--no-lock do not lock the repo, this allows some operations on read-only repos
-o, --option key=value set extended option (key=value, can be specified multiple times)
--password-command command specify a shell command to obtain a password (default: $RESTIC_PASSWORD_COMMAND)
-p, --password-file file read the repository password from a file (default: $RESTIC_PASSWORD_FILE)
-q, --quiet do not output comprehensive progress report
-r, --repo repository repository to backup to or restore from (default: $RESTIC_REPOSITORY)
--tls-client-cert file path to a file containing PEM encoded TLS client certificate and private key
-v, --verbose n be verbose (specify --verbose multiple times or level n)
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.
EXIT STATUS
===========
Exit status is 0 if the command was successful, and non-zero if there was any error.
Note that some issues such as unreadable or deleted files during backup
currently doesn't result in a non-zero error exit status.
Usage:
restic backup [flags] FILE/DIR [FILE/DIR] ...
Flags:
-e, --exclude pattern exclude a pattern (can be specified multiple times)
--exclude-caches excludes cache directories that are marked with a CACHEDIR.TAG file. See http://bford.info/cachedir/spec.html for the Cache Directory Tagging Standard
--exclude-file file read exclude patterns from a file (can be specified multiple times)
--exclude-if-present filename[:header] takes filename[:header], exclude contents of directories containing filename (except filename itself) if header of that file is as provided (can be specified multiple times)
--files-from file read the files to backup from file (can be combined with file args/can be specified multiple times)
-f, --force force re-reading the target files/directories (overrides the "parent" flag)
-h, --help help for backup
-H, --host hostname set the hostname for the snapshot manually. To prevent an expensive rescan use the "parent" flag
--iexclude pattern same as --exclude pattern but ignores the casing of filenames
--ignore-inode ignore inode number changes when checking for modified files
-x, --one-file-system exclude other file systems
--parent snapshot use this parent snapshot (default: last snapshot in the repo that has the same target files/directories)
--stdin read backup from stdin
--stdin-filename filename filename to use when reading from stdin (default "stdin")
--tag tag add a tag for the new snapshot (can be specified multiple times)
--time time time of the backup (ex. '2012-11-01 22:08:41') (default: now)
--with-atime store the atime for all files and directories
Global Flags:
--cacert file file to load root certificates from (default: use system certificates)
--cache-dir directory set the cache directory. (default: use system default cache directory)
--cleanup-cache auto remove old cache directories
--json set output mode to JSON for commands that support it
--key-hint key key ID of key to try decrypting first (default: $RESTIC_KEY_HINT)
--limit-download int limits downloads to a maximum rate in KiB/s. (default: unlimited)
--limit-upload int limits uploads to a maximum rate in KiB/s. (default: unlimited)
--no-cache do not use a local cache
--no-lock do not lock the repo, this allows some operations on read-only repos
-o, --option key=value set extended option (key=value, can be specified multiple times)
--password-command command specify a shell command to obtain a password (default: $RESTIC_PASSWORD_COMMAND)
-p, --password-file file read the repository password from a file (default: $RESTIC_PASSWORD_FILE)
-q, --quiet do not output comprehensive progress report
-r, --repo repository repository to backup to or restore from (default: $RESTIC_REPOSITORY)
--tls-client-cert file path to a file containing PEM encoded TLS client certificate and private key
-v, --verbose n be verbose (specify --verbose multiple times or level n)
Subcommand that support showing progress information such as ``backup``,
``check`` and ``prune`` will do so unless the quiet flag ``-q`` or
``--quiet`` is set. When running from a non-interactive console progress
reporting will be limited to once every 10 seconds to not fill your
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logs. Use ``backup`` with the quiet flag ``-q`` or ``--quiet`` to skip
the initial scan of the source directory, this may shorten the backup
time needed for large directories.
Additionally on Unix systems if ``restic`` receives a SIGUSR1 signal the
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current progress will be written to the standard output so you can check up
on the status at will.
Manage tags
-----------
Managing tags on snapshots is done with the ``tag`` command. The
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existing set of tags can be replaced completely, tags can be added or
removed. The result is directly visible in the ``snapshots`` command.
Let's say we want to tag snapshot ``590c8fc8`` with the tags ``NL`` and
``CH`` and remove all other tags that may be present, the following
command does that:
.. code-block:: console
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$ restic -r /srv/restic-repo 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
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$ restic -r /srv/restic-repo tag --tag NL --remove CH
create exclusive lock for repository
modified tags on 1 snapshots
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$ restic -r /srv/restic-repo tag --tag NL --add UK
create exclusive lock for repository
modified tags on 1 snapshots
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$ restic -r /srv/restic-repo tag --tag NL --remove NL
create exclusive lock for repository
modified tags on 1 snapshots
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$ restic -r /srv/restic-repo 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
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$ restic -r /srv/restic-repo list snapshots
d369ccc7d126594950bf74f0a348d5d98d9e99f3215082eb69bf02dc9b3e464c
The ``find`` command searches for a given
`pattern <https://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
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objects or their raw content.
.. code-block:: console
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$ restic -r /srv/restic-repo 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
Getting information about repository data
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Use the ``stats`` command to count up stats about the data in the repository.
There are different counting modes available using the ``--mode`` flag,
depending on what you want to calculate. The default is the restore size, or
the size required to restore the files:
- ``restore-size`` (default) counts the size of the restored files.
- ``files-by-contents`` counts the total size of unique files as given by their
contents. This can be useful since a file is considered unique only if it has
unique contents. Keep in mind that a small change to a large file (even when the
file name/path hasn't changed) will cause them to look like different files, thus
essentially causing the whole size of the file to be counted twice.
- ``raw-data`` counts the size of the blobs in the repository, regardless of how many
files reference them. This tells you how much restic has reduced all your original
data down to (either for a single snapshot or across all your backups), and compared
to the size given by the restore-size mode, can tell you how much deduplication is
helping you.
- ``blobs-per-file`` is kind of a mix between files-by-contents and raw-data modes;
it is useful for knowing how much value your backup is providing you in terms of unique
data stored by file. Like files-by-contents, it is resilient to file renames/moves.
Unlike files-by-contents, it does not balloon to high values when large files have
small edits, as long as the file path stayed the same. Unlike raw-data, this mode
DOES consider how many files point to each blob such that the more files a blob is
referenced by, the more it counts toward the size.
For example, to calculate how much space would be
required to restore the latest snapshot (from any host that made it):
.. code-block:: console
$ restic stats latest
password is correct
Total File Count: 10538
Total Size: 37.824 GiB
If multiple hosts are backing up to the repository, the latest snapshot may not
be the one you want. You can specify the latest snapshot from only a specific
host by using the ``--host`` flag:
.. code-block:: console
$ restic stats --host myserver latest
password is correct
Total File Count: 21766
Total Size: 481.783 GiB
There we see that it would take 482 GiB of disk space to restore the latest
snapshot from "myserver".
But how much space does that snapshot take on disk? In other words, how much
has restic's deduplication helped? We can check:
.. code-block:: console
$ restic stats --host myserver --mode raw-data latest
password is correct
Total Blob Count: 340847
Total Size: 458.663 GiB
Comparing this size to the previous command, we see that restic has saved
about 23 GiB of space with deduplication.
Which mode you use depends on your exact use case. Some modes are more useful
across all snapshots, while others make more sense on just a single snapshot,
depending on what you're trying to calculate.
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
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$ restic -r /srv/restic-repo 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
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$ restic -r /srv/restic-repo 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 ``$XDG_CACHE_HOME/restic``)
* macOS: ``~/Library/Caches/restic``
* Windows: ``%LOCALAPPDATA%/restic``
The command line parameter ``--cache-dir`` or the environment variable
``$RESTIC_CACHE_DIR`` can 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.
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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.