7b11660f4f
... by first adding a preliminary index entry and making this fail if an index entry for the same blob already exists. A preliminary index entry is characterized by not yet being associated with a pack. Until now, these entries where added to the index just like final index entries using index.Store, which silently overwrites existing index entries. This commit adds a new method index.StoreInProgress which refuses to overwrite existing index entries and allows for creating preliminary index entries only. The existing method index.Store has not been changed and continues to silently overwrite existing index entries. This distinction is important, as otherwise, it would be impossible to update a preliminary index entry after the blob has been written to a pack. Resolves: restic#292
Restic Design Principles
Restic is a program that does backups right and was designed with the following principles in mind:
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Easy: Doing backups should be a frictionless process, otherwise you might be tempted to skip it. Restic should be easy to configure and use, so that, in the event of a data loss, you can just restore it. Likewise, restoring data should not be complicated.
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Fast: Backing up your data with restic should only be limited by your network or hard disk bandwidth so that you can backup your files every day. Nobody does backups if it takes too much time. Restoring backups should only transfer data that is needed for the files that are to be restored, so that this process is also fast.
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Verifiable: Much more important than backup is restore, so restic enables you to easily verify that all data can be restored.
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Secure: Restic uses cryptography to guarantee confidentiality and integrity of your data. The location the backup data is stored is assumed not to be a trusted environment (e.g. a shared space where others like system administrators are able to access your backups). Restic is built to secure your data against such attackers.
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Efficient: With the growth of data, additional snapshots should only take the storage of the actual increment. Even more, duplicate data should be de-duplicated before it is actually written to the storage back end to save precious backup space.
Build restic
Install Go/Golang (at least version 1.3), then run go run build.go,
afterwards you'll find the binary in the current directory:
$ go run build.go
$ ./restic --help
Usage:
restic [OPTIONS] <command>
Application Options:
-r, --repo= Repository directory to backup to/restore from
Help Options:
-h, --help Show this help message
Available commands:
backup save file/directory
cache manage cache
cat dump something
check check the repository
find find a file/directory
init create repository
key manage keys
list lists data
ls list files
restore restore a snapshot
snapshots show snapshots
unlock remove locks
version display version
A short demo recording can be found here:
Compatibility
Backward compatibility for backups is important so that our users are always able to restore saved data. Therefore restic follows Semantic Versioning to clearly define which versions are compatible. The repository and data structures contained therein are considered the "Public API" in the sense of Semantic Versioning.
We guarantee backward compatibility of all repositories within one major version; as long as we do not increment the major version, data can be read and restored. We strive to be fully backward compatible to all prior versions.
Contribute and Documentation
Contributions are welcome! More information can be found in
CONTRIBUTING.md. A document describing the design of
restic and the data structures stored on the back end is contained in
doc/Design.md.
The development environment is described in CONTRIBUTING.md.
Contact
If you discover a bug or find something surprising, please feel free to open a github issue. If you would like to chat about restic, there is also the IRC channel #restic on irc.freenode.net. Or just write me an email :)
Important: If you discover something that you believe to be a possible critical security problem, please do not open a GitHub issue but send an email directly to alexander@bumpern.de. If possible, please encrypt your email using PGP (0xD3F7A907).
Talks
The following talks will be or have been given about restic:
- 2015-08-23: A Solution to the Backup Inconvenience: Lecture at FROSCON 2015 in Bonn, Germany
- 2015-02-01: Lightning Talk at FOSDEM 2015: A short introduction (with slightly outdated command line)
- 2015-01-27: Talk about restic at CCC Aachen (in German)
License
Restic is licensed under "BSD 2-Clause License". You can find the complete text
in the file LICENSE.