Symantec's [http://www.symantec.com/business/backup-exec-system-recovery-desktop-edition BESR] allows full system backup and restore (virtual and physical)from any hardware with restore to dissimilar hardware. Conversion from P2V or V2P can also be scheduled. Install BESR on all windows computers connected to HDA and route backup to a folder on the HDA. Remember to set permissions on destination folders. Activate VSS copy so any open files are captured, optional threatcon can be used to trigger a backup if a threat becomes widespread.

Alternatively BESR can be installed on a central windows machine with agents deployed on all other windows and Linux machines and using the new Linux media server agent (replaces RALUS) backup directly on the Linux HDA. This way you maintain a catalogue of all backups and can trigger them from a central console.

BESR is only for windows machines connected to the HDA but is a great solution to protecting these machines and allows LIVE single pass backup and granular restore of files, saves doing an image and a file backup. Less space less time. An agent is available to backup Linux but another option is to boot the HDA on the recovery disk and create a cold image of the server.