A. Microsoft announced on August 19, 2008, that Exchange Server 2007 SP1 is supported under Windows Server 2008 Hyper-V and other hypervisors that are part of the Microsoft Server Virtualization Validation Program, per the Microsoft Exchange Team blog post at http://msexchangeteam.com/archive/2008/08/19/449621.aspx. You can find additional information about Microsoft’s Exchange-virtualization support policies at http://technet.microsoft.com/en-us/library/cc794548.aspx.
Essentially all Exchange 2007 SP1 roles except for the Unified Messaging role are supported under Hyper-V, if Exchange is running on a Windows 2008 child partition (guest). In addition, supported disks must be virtual fixed-size (dynamic size is not supported), SCSI pass-through, or iSCSI.
Although high-availability features such as cluster continuous replication (CCR) and standby continuous replication (SCR) are supported in virtualized Exchange environments, you should not combine the Exchange high-availability solutions with Hyper-V high-availability features, such as a clustered virtualization server. You can, however, mix virtual and physical CCR or SCC.