True Server Clusters
If an NLB cluster is too limited in functionality for you, you should investigate a true server cluster. In a true server cluster, a group of machines have a single identity and work in tandem to manage and, in the event of failure, migrate applications away from problematic nodes and onto functional nodes. The nodes of the cluster use a common, shared resource database and log storage facility provided by a physical storage device that is located on a hardware bus shared by all members of the cluster.
The shared data facility does not support IDE disks, software RAID (including Windows-based dynamic RAID), dynamic disks or volumes, the EFS, mounted volumes and reparse points, or remote storage devices such as tape backup drives.
Three types of clusters are supported by Windows Server 2003 in the Enterprise and Datacenter editions of the product: single node clusters, which are useful in test and laboratory environments to see if applications and resources function in the manner intended but do not have any sort of fault-tolerant functionality; single quorum device clusters, which are the most common and most functional type of cluster used in production because of their multiple nodes; and majority node set clusters, which function as a cluster but without a shared physical storage device, something required of the other two types. Majority node set clusters are useful if you do not have a SCSI-based SAN or if the members of a cluster are spread out over ...