Check out this article from Don Norbeck, Director of Product Development at Sungard.

Today’s IT organizations are faced with the daunting task of optimizing all aspects of their departments, including people, processes and technology. Virtualization—one particularly exciting example of this trend—has been defined as the pooling of various IT resources in a way that masks the physical nature and boundaries of those resources from the users. It promises to unlock underutilized server capacity through partitioning, enabling the ability to run multiple operating systems on one server. The most obvious benefits of virtualization are not just the ability to achieve higher server and overall computing infrastructure utilization, but also improved responsiveness and flexibility—since virtual resources can be moved or modified dynamically to reflect changing business needs.

Disaster recovery represents an innovative application of virtualization technology. Traditionally, disaster recovery has been achieved through the use of redundant infrastructures and systems housed in remote locations, away from primary datacenters. While an effective strategy, many IT organizations find it difficult if not impossible to buy and maintain “two of everything.”

Through the virtual partitioning of hardware to support multiple operating systems, virtualization purports to do away with the “two of everything” approach by delivering a level of redundancy that can be used for disaster recovery purposes—either on the same hardware or on a different piece of equipment within the same data center. Known as virtualized DR, this practice enables local availability within a single data center by facilitating failover from one partition to another partition in the same server, or in another server located in the same data center.

Virtualization is rapidly gaining momentum as a means of supporting business critical applications. However, the notion of local availability delivered on a single server or within a single datacenter directly contradicts a key tenet of the Seven Tiers of Disaster Recovery, which states unequivocally that a DR strategy with no off-site data may mean, quite possibly, no recovery (the Seven Tiers were originally defined by SHARE, a user group for IBM mainframe computers, in the early 1990’s to help identify the various methods of recovering mission-critical computer systems as required to support business continuity. Since then, the Seven Tiers have evolved into an industry-standard discussion).

Neither virtualization nor virtualized DR is a panacea. Rather, they are complex initiatives requiring careful, ongoing consideration of key issues, including:

• Increased criticality of virtual servers
• Increased complexity for server administration and management
• Change management and architecting the infrastructure migration from physical to virtual environment
• Balancing investment versus higher utilization rates
• Need for new skill sets and processes

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Read the entire article, here.