Cisco Unity will continue to use the Disaster Recovery Backup and Restore Tool (DiRT) to provide backup of all Cisco Unity server-specific data including SQL databases, registry settings, greetings, recorded names, switch file configuration, routing rules, and subscriber passwords. If the server suffers a catastrophic failure, you must first rebuild it to the point where Cisco Unity is running as a clean, freshly installed system. At that point, the DiRT utility can be used to bring the server back to the point at which the last backup took place.
Note 
DiRT does not take the place of routing tape backups of your Microsoft Exchange or IBM Lotus Domino message store servers.
For more information, see the Maintenance Guide for Cisco Unity (With Microsoft Exchange) 
or the Maintenance Guide for Cisco Unity (With IBM Lotus Domino) .