A dynamic cluster disk group is a collection of one or more disks that behave as a single storage repository and which can potentially be accessed by different computers. Within each disk group, you can have dynamic volumes with different layouts.
You create a cluster disk group and volumes on only one node of a cluster. The volumes can be accessed by other nodes in a high-availability cluster by first deporting the cluster disk group from the current node and then importing it on the desired node. In a campus cluster, the volumes are mirrored across the storage arrays.
Before creating a disk group, consider the following:
The type of volume configurations that are required.
The number of LUNs required for the disk group.
The implications of backup and restore operations on the disk group setup.
The size of databases and logs which depend on the traffic load.
The number of disk groups and volumes that are needed for Exchange. Typically an SFW disk group corresponds to an Exchange storage group, with a separate volume for each database and for the transaction log.
For campus clusters, consider the following:
In a Microsoft cluster, plan to include a disk group for the mirrored quorum resource. If possible, use small disks. Microsoft recommends 500 MB for the quorum disk. The number of disks recommended are as follows: