Consolidating physical servers at the DR site eliminates the need for one-to-one mirrored physical machines and can deliver savings in power and cooling, management and maintenance. The portability of virtual machines also means that failback can occur to the original location or to a new one: either a virtual machine or a physical system with dissimilar hardware.

Another advantage is the ability to test DR more efficiently. Regular DR testing--confirming failover and failback processes,...