Vchanger may be used with the Bacula Open Source network backup system to emulate a magazine-based tape autoloader using disk partitions on fixed or removable disk drives as virtual magazines and files on those partitions as virtual tape volumes.
Without vchanger, Bacula has no right to claim it supports disk-based backup. Wtih vchanger, one gains the ability to use disks as virtual tape drives. Bacula should incorporate vchanger's functionality. This has been a complaint of mine for years.