About cluster disk groups and volumes
SFW uses disk groups to organize disks or LUNs for management purposes. A dynamic disk group is a collection of disks that is imported or deported as a single unit. A cluster disk group is a special type of dynamic disk group that is created on shared storage and is designed to be moved or to failover between hosts. In order to prevent data corruption a cluster disk group uses SCSI reservations to protect the shared disks and limits access to a single host at a time.
Volumes are logical entities that are comprised of portions of one or more physical disks and are accessed by a drive letter or mount point. Volumes can be configured for performance and high availability.
Note: 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. Note: If your storage devices are SCSI-3 compliant, and you wish to use SCSI-3 Persistent Group Reservations (PGR), you must enable SCSI-3 support using the Veritas Enterprise Administrator (VEA - Control Panel - System Settings). For more information, see theStorage Foundation Administrator's Guide.
Before you create a disk group, consider the following items:
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The type of volume configurations that are required
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The number of LUNs required for the disk group
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The implications of backup and restore operations on the disk group setup
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The size of databases and logs that depend on the traffic load
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The disk groups and number of disks on each site
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Types of volumes required and location of the plex of each volume in the storage array
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