BorgBackup (short: Borg) is a deduplicating backup program with compression and authenticated encryption, designed to efficiently back up data daily without consuming excessive storage space. It's a powerful, space-efficient solution that's particularly well-suited for system administrators and power users who need reliable, automated backup systems.
What makes Borg exceptional is its deduplication technology. At the chunk level, Borg identifies duplicate data segments across all backups and stores them only once, dramatically reducing storage requirements. This means you can keep dozens or even hundreds of daily backups without proportionally increasing storage costs.
Borg employs strong authenticated encryption using AES-256 in counter mode with HMAC-SHA256 for authentication, ensuring that your backups are secure both in transit and at rest. This makes it ideal for storing backups on untrusted remote servers or cloud storage, where data confidentiality is paramount.
The backup process is fast and efficient, using content-defined chunking to identify and eliminate duplicate data at the block level. Borg supports compression with multiple algorithms (lz4, zstd, zlib, lzma), allowing you to balance between backup speed and storage efficiency. The backup format is designed for reliability, with checksums to detect corruption and self-healing capabilities.
BorgBackup works seamlessly with remote repositories over SSH, making it perfect for off-site backups. You can back up to a remote server, NAS, or cloud storage provider that supports SSH/SFTP. The prune command intelligently manages backup retention policies, automatically deleting old backups based on configurable rules while maintaining the deduplication benefits.