Requirements for installing SnapManager in a Windows cluster

SnapManager is supported in Windows clusters with a maximum of eight nodes. Exchange Server 2003 requires a Windows cluster that uses shared LUN resources. Exchange Server 2007 supports two types of Windows cluster configurations--SCC and CCR.

The SCC, which uses LUN resources that are shared among all nodes in the cluster.
The CCR, which uses LUN resources that are dedicated to each of the two cluster nodes and are not shared among the nodes
For more information, see Microsoft Exchange server documentation.