BorgBackup: Deduplication with compression and authenticated encryption

BorgBackup is a deduplicating backup program that supports compression and authenticated encryption.

The main goal of BorgBackup is to provide an efficient and secure way to backup data. The data deduplication technique used makes BorgBackup suitable for daily backups since only changes are stored. The authenticated encryption technique makes it suitable for backups to not fully trusted targets.

Main features include:

Space efficient storage

Deduplication based on content-defined chunking is used to reduce the number of bytes stored: each file is split into a number of variable length chunks and only chunks that have never been seen before are added to the repository.

To deduplicate, all the chunks in the same repository are considered, no matter whether they come from different machines, from previous backups, from the same backup or even from the same single file.

Speed

• Performance critical code (chunking, compression, encryption) is implemented in C/Cython
• Local caching of files/chunks index data
• Quick detection of unmodified files

Data encryption

All data can be protected using 256-bit AES encryption, data integrity and authenticity is verified using HMAC-SHA256. Data is encrypted clientside.

Compression

All data can be compressed by lz4 (super fast, low compression), zlib (medium speed and compression) or lzma (low speed, high compression).

Off-site backups

BorgBackup can store data on any remote host accessible over SSH. If Borg is installed on the remote host, big performance gains can be achieved compared to using a network filesystem (sshfs, nfs, …).

Backups mountable as filesystems

Backup archives are mountable as userspace filesystems for easy interactive backup examination and restores (e.g. by using a regular file manager).

Easy installation on multiple platforms

The project offers single-file binaries that do not require installing anything – you can just run them on these platforms:

• Linux
• Mac OS X
• FreeBSD
• OpenBSD and NetBSD (no xattrs/ACLs support or binaries yet)
• Cygwin (not supported, no binaries yet)