A. Microsoft changed its support policy for virtualized clusters of SQL Server 2005 and 2008 on May 19, 2009. Before the change in policy, guest clusters (clustering inside the virtual machine) of SQL weren't supported. Under the new policy, documented at this site, clustering of both SQL Server 2005 and 2008 are supported in a virtual environment providing the guest OS is Windows Server 2008, the virtual environment meets the requirements of Windows 2008 Failover Clustering and the virtualization platform is certified as part of SVVP. Microsoft Hyper-V Server 2008 would, for example, be certified.
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