Bacula is an open source, network based computer back-up program.

Introduction

Bacula is a system for backing up computer files. In addition to an amusing name Bacula has an amusing slogan: "It comes by night and sucks the vital essence from your computers."

Bacula installations can backup one or more computer(s). When multiple computers are backed up data is moved over the network that connects those computers. The software supports many operating systems, including Linux, Solaris, FreeBSD, NetBSD, Windows, Mac OS X, OpenBSD, HP-UX, Tru64 and IRIX.

The backup data can be stored on various media like Tape, DVD or On-line Disk. In comparison with other high-end backup utilities Bacula has little to no firewall issues and good performance.

Bacula which is open source software is licensed under a modified version of the GPL2 license.

Structure

A Bacula installation will have three kinds of daemons, i.e:DirectorControls all backup management tasks, controls database access, initiates backups
Storage DaemonHandles Backup media and receives backup data
File DaemonHandles data access, handles client-side encryption and compression, and of course the actual reading or restoring of data

The Director manages everything, the client and storage deamons run as its subordinates and have not direct control of the back up process

These deamons run on machines of three kinds:Client machinesthe machines that contain the files to be backed up
Storage machinesmachines that contain the media used to store the backups
Backup Serversthat orchestrate the backup process

While this structure suggests that the three daemons should run on three different machines, an equally valid setup is to run all three daemons on the machine that controls the backup process and mount any remote files and storage resources into its filesystem over SMB or NFS, for the file and storage daemons to access. However, in practice, the Director and Storage Daemon are often run on one machine (often referred to as the Bacula Server). The File Daemon is then run on each machine to be backed up (which of course includes the Bacula server).