Bacula

Bacula is an open-source backup, recovery, and verification software for networks. It runs on Linux, Unix, Windows, and macOS, and provides a modular set of programs to automate backup operations across multiple machines.

The core architecture consists of the Director, Storage Daemon, and File Daemon, plus a Catalog database and a text console client (bconsole). The Director coordinates backup and restore jobs; File Daemons run on client hosts to read data; Storage Daemons manage storage devices; the Catalog stores metadata about backups and job history.

Backups are defined as Jobs and Jobdefs, can be full, incremental, or differential, and are organized with retention policies and media pools. Data is transferred securely over the network using TLS; optional encryption for data at rest is achieved via external mechanisms. Bacula can compress data during transfers or storage.

Storage targets include local disks, tape libraries, and cloud storage, accessible via Storage Daemons with plug-ins; Bacula supports cloud storage backends such as Amazon S3, Google Cloud Storage, and Microsoft Azure.

The Catalog database can be SQLite, MySQL/MariaDB, or PostgreSQL.

Bacula is distributed under the GNU General Public License and has a community edition widely used in small to large environments, often integrated with scripts and third-party interfaces for management.