BorgBackup — efficient, encrypted backups with serious storage savings
BorgBackup (often just “Borg”) is an open-source backup tool that runs from the command line. It’s known for its storage efficiency, thanks to block-level deduplication and compression, and for its security, with client-side encryption built in. Borg works on Linux, macOS, and BSD, and can run on Windows through WSL or Cygwin.
It uses a repository model: all backups go into a single structured store, where duplicate blocks are only saved once. Compression (LZ4, Zstandard, and others) keeps backups smaller, while encryption ensures the storage location never sees unprotected data. Repositories can be local, on network shares, or accessed over SSH.
It’s a tool that rewards scripting and automation — ideal for servers, workstations, or NAS devices that need efficient, regular backups without a heavy GUI.
Capabilities
| Feature | Description |
| Cross-Platform | Linux, macOS, BSD; Windows via WSL/Cygwin |
| Deduplication | Block-level, content-based — saves only unique data |
| Compression | LZ4 (fast), Zstd (balanced), others for higher compression |
| Encryption | Authenticated AES-CTR with HMAC |
| Repository Locations | Local, mounted shares, SSH remotes |
| Integrity Checks | `borg check` to verify repository health |
| Pruning | Retention policies to clean out old backups |
| Automation Friendly | Works well with cron, systemd timers, or scripts |
Deployment Notes
– Best suited for environments where CLI access is normal.
– Initial backup can be large; incrementals are much faster.
– SSH-based repositories benefit from key-based authentication.
– Deduplication works across all backups in the same repository — plan to keep related jobs together.
– On slow links, compression choice can affect performance noticeably.
Quick Start (Linux Example)
# Create a repository
borg init –encryption=repokey /path/to/repo
# Backup a directory
borg create /path/to/repo::backup-$(date +%Y-%m-%d) /home/user
# List backups
borg list /path/to/repo
# Restore a backup
borg extract /path/to/repo::backup-2025-08-13
Where it fits
– Server backups to local or remote storage with deduplication savings.
– Encrypted archives of critical data on untrusted storage.
– Workstation backups automated via cron or systemd.
– Long-term retention policies without ballooning storage use.
– Admin workflows that favor CLI tools over GUI interfaces.