forked from TrueCloudLab/restic
1d69341e88
This adds support for the following environment variables, which were previously missing: OS_USER_ID User ID for keystone v3 authentication OS_USER_DOMAIN_ID User domain ID for keystone v3 authentication OS_PROJECT_DOMAIN_ID Project domain ID for keystone v3 authentication OS_TRUST_ID Trust ID for keystone v3 authentication
528 lines
22 KiB
ReStructuredText
528 lines
22 KiB
ReStructuredText
..
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Normally, there are no heading levels assigned to certain characters as the structure is
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determined from the succession of headings. However, this convention is used in Python’s
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Style Guide for documenting which you may follow:
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# with overline, for parts
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* for chapters
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= for sections
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- for subsections
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^ for subsubsections
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" for paragraphs
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##########
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Backing up
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##########
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Now we're ready to backup some data. The contents of a directory at a
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specific point in time is called a "snapshot" in restic. Run the
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following command and enter the repository password you chose above
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again:
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.. code-block:: console
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$ restic -r /srv/restic-repo --verbose backup ~/work
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open repository
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enter password for repository:
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password is correct
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lock repository
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load index files
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start scan
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start backup
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scan finished in 1.837s
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processed 1.720 GiB in 0:12
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Files: 5307 new, 0 changed, 0 unmodified
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Dirs: 1867 new, 0 changed, 0 unmodified
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Added: 1.200 GiB
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snapshot 40dc1520 saved
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As you can see, restic created a backup of the directory and was pretty
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fast! The specific snapshot just created is identified by a sequence of
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hexadecimal characters, ``40dc1520`` in this case.
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You can see that restic tells us it processed 1.720 GiB of data, this is the
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size of the files and directories in ``~/work`` on the local file system. It
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also tells us that only 1.200 GiB was added to the repository. This means that
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some of the data was duplicate and restic was able to efficiently reduce it.
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If you don't pass the ``--verbose`` option, restic will print less data. You'll
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still get a nice live status display. Be aware that the live status shows the
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processed files and not the transferred data. Transferred volume might be lower
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(due to de-duplication) or higher.
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On Windows, the ``--use-fs-snapshot`` option will use Windows' Volume Shadow Copy
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Service (VSS) when creating backups. Restic will transparently create a VSS
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snapshot for each volume that contains files to backup. Files are read from the
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VSS snapshot instead of the regular filesystem. This allows to backup files that are
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exclusively locked by another process during the backup.
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By default VSS ignores Outlook OST files. This is not a restriction of restic
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but the default Windows VSS configuration. The files not to snapshot are
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configured in the Windows registry under the following key:
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.. code-block:: console
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HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\BackupRestore\FilesNotToSnapshot
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For more details refer the official Windows documentation e.g. the article
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``Registry Keys and Values for Backup and Restore``.
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If you run the backup command again, restic will create another snapshot of
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your data, but this time it's even faster and no new data was added to the
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repository (since all data is already there). This is de-duplication at work!
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.. code-block:: console
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$ restic -r /srv/restic-repo backup --verbose ~/work
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open repository
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enter password for repository:
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password is correct
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lock repository
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load index files
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using parent snapshot d875ae93
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start scan
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start backup
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scan finished in 1.881s
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processed 1.720 GiB in 0:03
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Files: 0 new, 0 changed, 5307 unmodified
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Dirs: 0 new, 0 changed, 1867 unmodified
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Added: 0 B
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snapshot 79766175 saved
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You can even backup individual files in the same repository (not passing
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``--verbose`` means less output):
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.. code-block:: console
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$ restic -r /srv/restic-repo backup ~/work.txt
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enter password for repository:
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password is correct
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snapshot 249d0210 saved
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If you're interested in what restic does, pass ``--verbose`` twice (or
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``--verbose=2``) to display detailed information about each file and directory
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restic encounters:
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.. code-block:: console
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$ echo 'more data foo bar' >> ~/work.txt
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$ restic -r /srv/restic-repo backup --verbose --verbose ~/work.txt
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open repository
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enter password for repository:
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password is correct
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lock repository
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load index files
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using parent snapshot f3f8d56b
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start scan
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start backup
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scan finished in 2.115s
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modified /home/user/work.txt, saved in 0.007s (22 B added)
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modified /home/user/, saved in 0.008s (0 B added, 378 B metadata)
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modified /home/, saved in 0.009s (0 B added, 375 B metadata)
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processed 22 B in 0:02
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Files: 0 new, 1 changed, 0 unmodified
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Dirs: 0 new, 2 changed, 0 unmodified
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Data Blobs: 1 new
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Tree Blobs: 3 new
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Added: 1.116 KiB
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snapshot 8dc503fc saved
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In fact several hosts may use the same repository to backup directories
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and files leading to a greater de-duplication.
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Please be aware that when you backup different directories (or the
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directories to be saved have a variable name component like a
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time/date), restic always needs to read all files and only afterwards
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can compute which parts of the files need to be saved. When you backup
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the same directory again (maybe with new or changed files) restic will
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find the old snapshot in the repo and by default only reads those files
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that are new or have been modified since the last snapshot. This is
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decided based on the following attributes of the file in the file system:
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* Type (file, symlink, or directory?)
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* Modification time
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* Size
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* Inode number (internal number used to reference a file in a file system)
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Now is a good time to run ``restic check`` to verify that all data
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is properly stored in the repository. You should run this command regularly
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to make sure the internal structure of the repository is free of errors.
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Excluding Files
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***************
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You can exclude folders and files by specifying exclude patterns, currently
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the exclude options are:
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- ``--exclude`` Specified one or more times to exclude one or more items
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- ``--iexclude`` Same as ``--exclude`` but ignores the case of paths
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- ``--exclude-caches`` Specified once to exclude folders containing a special file
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- ``--exclude-file`` Specified one or more times to exclude items listed in a given file
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- ``--iexclude-file`` Same as ``exclude-file`` but ignores cases like in ``--iexclude``
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- ``--exclude-if-present foo`` Specified one or more times to exclude a folder's content if it contains a file called ``foo`` (optionally having a given header, no wildcards for the file name supported)
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- ``--exclude-larger-than size`` Specified once to excludes files larger than the given size
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Please see ``restic help backup`` for more specific information about each exclude option.
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Let's say we have a file called ``excludes.txt`` with the following content:
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::
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# exclude go-files
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*.go
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# exclude foo/x/y/z/bar foo/x/bar foo/bar
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foo/**/bar
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It can be used like this:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup ~/work --exclude="*.c" --exclude-file=excludes.txt
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This instructs restic to exclude files matching the following criteria:
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* All files matching ``*.c`` (parameter ``--exclude``)
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* All files matching ``*.go`` (second line in ``excludes.txt``)
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* All files and sub-directories named ``bar`` which reside somewhere below a directory called ``foo`` (fourth line in ``excludes.txt``)
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Patterns use `filepath.Glob <https://golang.org/pkg/path/filepath/#Glob>`__ internally,
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see `filepath.Match <https://golang.org/pkg/path/filepath/#Match>`__ for
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syntax. Patterns are tested against the full path of a file/dir to be saved,
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even if restic is passed a relative path to save.
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Environment-variables in exclude files are expanded with `os.ExpandEnv <https://golang.org/pkg/os/#ExpandEnv>`__,
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so ``/home/$USER/foo`` will be expanded to ``/home/bob/foo`` for the user ``bob``.
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To get a literal dollar sign, write ``$$`` to the file. Note that tilde (``~``) expansion does not work, please use the ``$HOME`` environment variable instead.
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Patterns need to match on complete path components. For example, the pattern ``foo``:
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* matches ``/dir1/foo/dir2/file`` and ``/dir/foo``
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* does not match ``/dir/foobar`` or ``barfoo``
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A trailing ``/`` is ignored, a leading ``/`` anchors the pattern at the root directory.
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This means, ``/bin`` matches ``/bin/bash`` but does not match ``/usr/bin/restic``.
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Regular wildcards cannot be used to match over the directory separator ``/``.
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For example: ``b*ash`` matches ``/bin/bash`` but does not match ``/bin/ash``.
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For this, the special wildcard ``**`` can be used to match arbitrary
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sub-directories: The pattern ``foo/**/bar`` matches:
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* ``/dir1/foo/dir2/bar/file``
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* ``/foo/bar/file``
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* ``/tmp/foo/bar``
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Spaces in patterns listed in an exclude file can be specified verbatim. That is,
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in order to exclude a file named ``foo bar star.txt``, put that just as it reads
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on one line in the exclude file. Please note that beginning and trailing spaces
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are trimmed - in order to match these, use e.g. a ``*`` at the beginning or end
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of the filename.
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Spaces in patterns listed in the other exclude options (e.g. ``--exclude`` on the
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command line) are specified in different ways depending on the operating system
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and/or shell. Restic itself does not need any escaping, but your shell may need
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some escaping in order to pass the name/pattern as a single argument to restic.
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On most Unixy shells, you can either quote or use backslashes. For example:
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* ``--exclude='foo bar star/foo.txt'``
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* ``--exclude="foo bar star/foo.txt"``
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* ``--exclude=foo\ bar\ star/foo.txt``
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By specifying the option ``--one-file-system`` you can instruct restic
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to only backup files from the file systems the initially specified files
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or directories reside on. In other words, it will prevent restic from crossing
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filesystem boundaries when performing a backup.
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For example, if you backup ``/`` with this option and you have external
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media mounted under ``/media/usb`` then restic will not back up ``/media/usb``
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at all because this is a different filesystem than ``/``. Virtual filesystems
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such as ``/proc`` are also considered different and thereby excluded when
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using ``--one-file-system``:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup --one-file-system /
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Please note that this does not prevent you from specifying multiple filesystems
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on the command line, e.g:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup --one-file-system / /media/usb
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will back up both the ``/`` and ``/media/usb`` filesystems, but will not
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include other filesystems like ``/sys`` and ``/proc``.
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.. note:: ``--one-file-system`` is currently unsupported on Windows, and will
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cause the backup to immediately fail with an error.
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Files larger than a given size can be excluded using the `--exclude-larger-than`
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option:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup ~/work --exclude-larger-than 1M
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This excludes files in ``~/work`` which are larger than 1 MB from the backup.
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The default unit for the size value is bytes, so e.g. ``--exclude-larger-than 2048``
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would exclude files larger than 2048 bytes (2 kilobytes). To specify other units,
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suffix the size value with one of ``k``/``K`` for kilobytes, ``m``/``M`` for megabytes,
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``g``/``G`` for gigabytes and ``t``/``T`` for terabytes (e.g. ``1k``, ``10K``, ``20m``,
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``20M``, ``30g``, ``30G``, ``2t`` or ``2T``).
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Including Files
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***************
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The options ``--files-from``, ``--files-from-verbatim`` and ``--files-from-raw``
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allow you to list files that should be backed up in a file, rather than on the
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command line. This is useful when a lot of files have to be backed up that are
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not in the same folder.
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The argument passed to ``--files-from`` must be the name of a text file that
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contains one pattern per line. The file must be encoded as UTF-8, or UTF-16
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with a byte-order mark. Leading and trailing whitespace is removed from the
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patterns. Empty lines and lines starting with a ``#`` are ignored.
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The patterns are expanded, when the file is read, by the Go function
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`filepath.Glob <https://golang.org/pkg/path/filepath/#Glob>`__.
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The option ``--files-from-verbatim`` has the same behavior as ``--files-from``,
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except that it contains literal filenames. It does expand patterns; filenames
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are listed verbatim. Lines starting with a ``#`` are not ignored; leading and
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trailing whitespace is not trimmed off. Empty lines are still allowed, so that
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files can be grouped.
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``--files-from-raw`` is a third variant that requires filenames to be terminated
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by a zero byte (the NUL character), so that it can even handle filenames that
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contain newlines or are not encoded as UTF-8 (except on Windows, where the
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listed filenames must still be encoded in UTF-8).
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This option is the safest choice when generating filename lists from a script.
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Its file format is the output format generated by GNU find's ``-print0`` option.
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All three arguments interpret the argument ``-`` as standard input.
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In all cases, paths may be absolute or relative to ``restic backup``'s
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working directory.
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For example, maybe you want to backup files which have a name that matches a
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certain regular expression pattern (uses GNU find):
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.. code-block:: console
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$ find /tmp/somefiles -regex PATTERN -print0 > /tmp/files_to_backup
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You can then use restic to backup the filtered files:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup --files-from-raw /tmp/files_to_backup
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You can combine all three options with each other and with the normal file arguments:
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.. code-block:: console
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$ restic backup --files-from /tmp/files_to_backup /tmp/some_additional_file
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$ restic backup --files-from /tmp/glob-pattern --files-from-raw /tmp/generated-list /tmp/some_additional_file
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Comparing Snapshots
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*******************
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Restic has a `diff` command which shows the difference between two snapshots
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and displays a small statistic, just pass the command two snapshot IDs:
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.. code-block:: console
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$ restic -r /srv/restic-repo diff 5845b002 2ab627a6
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password is correct
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comparing snapshot ea657ce5 to 2ab627a6:
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C /restic/cmd_diff.go
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+ /restic/foo
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C /restic/restic
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Files: 0 new, 0 removed, 2 changed
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Dirs: 1 new, 0 removed
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Others: 0 new, 0 removed
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Data Blobs: 14 new, 15 removed
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Tree Blobs: 2 new, 1 removed
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Added: 16.403 MiB
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Removed: 16.402 MiB
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Backing up special items and metadata
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*************************************
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**Symlinks** are archived as symlinks, ``restic`` does not follow them.
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When you restore, you get the same symlink again, with the same link target
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and the same timestamps.
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If there is a **bind-mount** below a directory that is to be saved, restic descends into it.
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**Device files** are saved and restored as device files. This means that e.g. ``/dev/sda`` is
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archived as a block device file and restored as such. This also means that the content of the
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corresponding disk is not read, at least not from the device file.
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By default, restic does not save the access time (atime) for any files or other
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items, since it is not possible to reliably disable updating the access time by
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restic itself. This means that for each new backup a lot of metadata is
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written, and the next backup needs to write new metadata again. If you really
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want to save the access time for files and directories, you can pass the
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``--with-atime`` option to the ``backup`` command.
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In filesystems that do not support inode consistency, like FUSE-based ones and pCloud, it is
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possible to ignore inode on changed files comparison by passing ``--ignore-inode`` to
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``backup`` command.
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Reading data from stdin
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***********************
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Sometimes it can be nice to directly save the output of a program, e.g.
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``mysqldump`` so that the SQL can later be restored. Restic supports
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this mode of operation, just supply the option ``--stdin`` to the
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``backup`` command like this:
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.. code-block:: console
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$ set -o pipefail
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$ mysqldump [...] | restic -r /srv/restic-repo backup --stdin
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This creates a new snapshot of the output of ``mysqldump``. You can then
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use e.g. the fuse mounting option (see below) to mount the repository
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and read the file.
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By default, the file name ``stdin`` is used, a different name can be
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specified with ``--stdin-filename``, e.g. like this:
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.. code-block:: console
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$ mysqldump [...] | restic -r /srv/restic-repo backup --stdin --stdin-filename production.sql
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The option ``pipefail`` is highly recommended so that a non-zero exit code from
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one of the programs in the pipe (e.g. ``mysqldump`` here) makes the whole chain
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return a non-zero exit code. Refer to the `Use the Unofficial Bash Strict Mode
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<http://redsymbol.net/articles/unofficial-bash-strict-mode/>`__ for more
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details on this.
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Tags for backup
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***************
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Snapshots can have one or more tags, short strings which add identifying
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information. Just specify the tags for a snapshot one by one with ``--tag``:
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.. code-block:: console
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$ restic -r /srv/restic-repo backup --tag projectX --tag foo --tag bar ~/work
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[...]
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The tags can later be used to keep (or forget) snapshots with the ``forget``
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command. The command ``tag`` can be used to modify tags on an existing
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snapshot.
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Space requirements
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******************
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Restic currently assumes that your backup repository has sufficient space
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for the backup operation you are about to perform. This is a realistic
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assumption for many cloud providers, but may not be true when backing up
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to local disks.
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Should you run out of space during the middle of a backup, there will be
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some additional data in the repository, but the snapshot will never be
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created as it would only be written at the very (successful) end of
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the backup operation. Previous snapshots will still be there and will still
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work.
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Environment Variables
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*********************
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In addition to command-line options, restic supports passing various options in
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environment variables. The following lists these environment variables:
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.. code-block:: console
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RESTIC_REPOSITORY_FILE Name of file containing the repository location (replaces --repository-file)
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RESTIC_REPOSITORY Location of repository (replaces -r)
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RESTIC_PASSWORD_FILE Location of password file (replaces --password-file)
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RESTIC_PASSWORD The actual password for the repository
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RESTIC_PASSWORD_COMMAND Command printing the password for the repository to stdout
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RESTIC_KEY_HINT ID of key to try decrypting first, before other keys
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RESTIC_CACHE_DIR Location of the cache directory
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RESTIC_PROGRESS_FPS Frames per second by which the progress bar is updated
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TMPDIR Location for temporary files
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AWS_ACCESS_KEY_ID Amazon S3 access key ID
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AWS_SECRET_ACCESS_KEY Amazon S3 secret access key
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AWS_DEFAULT_REGION Amazon S3 default region
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ST_AUTH Auth URL for keystone v1 authentication
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ST_USER Username for keystone v1 authentication
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ST_KEY Password for keystone v1 authentication
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OS_AUTH_URL Auth URL for keystone authentication
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OS_REGION_NAME Region name for keystone authentication
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OS_USERNAME Username for keystone authentication
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OS_USER_ID User ID for keystone v3 authentication
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OS_PASSWORD Password for keystone authentication
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OS_TENANT_ID Tenant ID for keystone v2 authentication
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OS_TENANT_NAME Tenant name for keystone v2 authentication
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OS_USER_DOMAIN_NAME User domain name for keystone authentication
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OS_USER_DOMAIN_ID User domain ID for keystone v3 authentication
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OS_PROJECT_NAME Project name for keystone authentication
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OS_PROJECT_DOMAIN_NAME Project domain name for keystone authentication
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OS_PROJECT_DOMAIN_ID Project domain ID for keystone v3 authentication
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OS_TRUST_ID Trust ID for keystone v3 authentication
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OS_APPLICATION_CREDENTIAL_ID Application Credential ID (keystone v3)
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OS_APPLICATION_CREDENTIAL_NAME Application Credential Name (keystone v3)
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OS_APPLICATION_CREDENTIAL_SECRET Application Credential Secret (keystone v3)
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OS_STORAGE_URL Storage URL for token authentication
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OS_AUTH_TOKEN Auth token for token authentication
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B2_ACCOUNT_ID Account ID or applicationKeyId for Backblaze B2
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B2_ACCOUNT_KEY Account Key or applicationKey for Backblaze B2
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|
|
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AZURE_ACCOUNT_NAME Account name for Azure
|
|
AZURE_ACCOUNT_KEY Account key for Azure
|
|
|
|
GOOGLE_PROJECT_ID Project ID for Google Cloud Storage
|
|
GOOGLE_APPLICATION_CREDENTIALS Application Credentials for Google Cloud Storage (e.g. $HOME/.config/gs-secret-restic-key.json)
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RCLONE_BWLIMIT rclone bandwidth limit
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|
|
|
See :ref:`caching` for the rules concerning cache locations when
|
|
``RESTIC_CACHE_DIR`` is not set.
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|
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The external programs that restic may execute include ``rclone`` (for rclone
|
|
backends) and ``ssh`` (for the SFTP backend). These may respond to further
|
|
environment variables and configuration files; see their respective manuals.
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|
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|
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Exit status codes
|
|
*****************
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|
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Restic returns one of the following exit status codes after the backup command is run:
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|
|
* 0 when the backup was successful (snapshot with all source files created)
|
|
* 1 when there was a fatal error (no snapshot created)
|
|
* 3 when some source files could not be read (incomplete snapshot with remaining files created)
|
|
|
|
Fatal errors occur for example when restic is unable to write to the backup destination, when
|
|
there are network connectivity issues preventing successful communication, or when an invalid
|
|
password or command line argument is provided. When restic returns this exit status code, one
|
|
should not expect a snapshot to have been created.
|
|
|
|
Source file read errors occur when restic fails to read one or more files or directories that
|
|
it was asked to back up, e.g. due to permission problems. Restic displays the number of source
|
|
file read errors that occurred while running the backup. If there are errors of this type,
|
|
restic will still try to complete the backup run with all the other files, and create a
|
|
snapshot that then contains all but the unreadable files.
|
|
|
|
One can use these exit status codes in scripts and other automation tools, to make them aware of
|
|
the outcome of the backup run. To manually inspect the exit code in e.g. Linux, run ``echo $?``.
|