The ability to convert physical computers and servers to virtual machines is an often an understated benefit of server virtualization. Virtual Servers are essentially flat files stored in a proprietary format.These files can be created periodically and stored on backup media for disaster recovery purposes. Business’s that have have strict recovery times and need greater availability may virtualize their physical servers and have these virtual machines hosted on physical servers located offsite. The Physical servers at the companies main office and The Virtual Servers offsite could be configured to sync with each other while clustered in master and slave setup with the Virtual Machines serving as slaves backing up a their physical masters. If a physical server goes down a Virtual server will be able to handle processing in few seconds. Tools such as Double Take can be used to synchronize the data residing in disparate locations while a WAN circuit is needed to link both locations .