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While most network executives are looking at server virtualization to reduce hardware costs, the technology also could offer a budgetary bonus: less-expensive disaster recovery. With disaster-facility contracts easily costing upward of $30,000 per month, killing off that budget line item is tempting.

"One of the hardest parts budget-wise [in IT] is disaster recovery and its incredible price tag. Traditionally, you had to duplicate everything you've got in one data center to another and then pray that you never have to use it," says Jason Brougham, enterprise network manager for American Medical Response, a Greenwood Village, Colo., ambulance service company with 18,000 employees and 255 locations nationwide. "The only way you can afford to build true disaster recovery is to run hot to hot, with both data centers active all the time on servers using virtualization."

Companies with virtualized servers and storage-area networks (SAN) in disparate data centers already have most of the pieces in place to take on in-house disaster recovery: They have a potential back-up location in a faraway spot (that likely won't be affected by the disaster). They have network connections between the two sites. Their virtualization and load-balancing software would let one server or SAN take over for another almost instantly if a short-term failure occurs (from routine maintenance to a few hours of blackout).

Network executives easily can make the common-sense leap for full-fledged in-house disaster recovery. If servers float away in a storm or are otherwise permanently damaged, one data center can become the backup for another. Even if you don't bring disaster recovery completely in-house, virtualization can help save money on the facility contract. Fewer virtualized servers do the work of more physical servers.

"The pieces of hardware become less critical in a virtualized environment - if there are 400 servers, with virtualization you could conceivably do disaster recovery on 20 servers. That might be reaching, but that's the idea," says Vivian Knoerle, principal consultant for Intellinet, a virtualization and disaster-recovery systems integrator in Atlanta. "If you do still use a disaster-recovery facility for hosting, the expense and hardware requirement can be less - because the number of physical servers can be far less."