Borgbackup
By the BorgBackup open-source project
BorgBackup, commonly called Borg, is an open-source deduplicating backup program that creates space-efficient, encrypted archives of files, typically stored on a local disk or a remote server accessed over SSH. It deduplicates data at the…
Definition
BorgBackup, commonly called Borg, is an open-source deduplicating backup program that creates space-efficient, encrypted archives of files, typically stored on a local disk or a remote server accessed over SSH. It deduplicates data at the chunk level across all archives in a repository, so repeated backups of mostly unchanged data consume very little additional space, and it supports compression and authenticated encryption to keep archives both small and secure. System administrators use it to run frequent, low-overhead backups of servers and workstations.
Overview
BorgBackup was built to solve the problem of backup storage bloat: naive full or even simple incremental backups tend to duplicate large amounts of unchanged data across snapshots, consuming disk space and bandwidth that could be avoided. Borg's deduplication model means that after an initial full backup, subsequent runs typically transfer and store only the data that has actually changed, regardless of how large the overall dataset is. Mechanically, Borg splits files into variable-length chunks based on their content, computes a hash for each chunk, and stores each unique chunk only once in a repository, whether it came from the same file backed up repeatedly or from entirely different files that happen to share content. Archives reference these chunks rather than storing file copies directly, so a repository holding months of daily backups can be a small fraction of the size that a naive backup approach would require. Borg encrypts data client-side and can compress it, and it supports repository access over SSH to a remote host running the Borg binary, or to local and mounted storage. Compared to Restic, Borg has historically been more tied to local and SSH-accessible repositories, with cloud object storage typically reached indirectly through a mounting tool or paired with Rclone, whereas Restic has broader native cloud backend support built in. Compared to Duplicity, which builds incremental chains from a full backup and can be slower to restore from deep in a chain, Borg's chunk-based deduplication generally makes both backup and restore operations more consistent in speed regardless of how many archives exist in the repository. In practice, Borg is widely used for automated nightly or hourly backups of Linux servers, developer workstations, and NAS devices, often scheduled through cron and paired with a pruning policy that keeps a defined retention schedule of daily, weekly, and monthly archives. Its efficient deduplication makes it practical to keep years of history in a repository that would be unmanageably large with simpler tools. Limitations include the requirement that repository access generally needs either local filesystem access or an SSH connection to a host running compatible Borg tooling, making direct cloud object storage access less native than in Restic, and a single shared repository can become a bottleneck for concurrent access from multiple machines. Teams needing native multi-cloud backend support or centralized backup management across many machines may prefer Restic or a dedicated backup platform instead. Borg's long track record and mature command set have made it a common choice behind higher-level backup wrappers such as Vorta and BorgMatic, which add scheduling, notifications, and a graphical layer over the core tool. As with any deduplicating backup system, periodic integrity checks of the repository are important, since a damaged repository could otherwise silently affect every archive that shares its chunks, not just the most recent backup.
Key Features
- Deduplicates data at the chunk level across all archives
- Encrypts and optionally compresses archives client-side
- Stores repositories locally or on remote hosts via SSH
- Supports flexible retention and pruning policies
- Keeps backup and restore speed consistent as history grows
- Provides mountable archives for browsing backed-up files
- Runs efficiently on modest hardware and network links
- Offers a mature command-line interface for scripting