1.5.7 Volume Managers

Sun Cluster supports three volume managers: Solstice DiskSuite, Sun StorEdge Volume Manager (SSVM), and Cluster Volume Manager (CVM). These volume managers provide mirroring, concatenating, and striping for use by Sun Cluster. SSVM and CVM also enable you to set up and administer RAID5 under Sun Cluster. Volume managers organize disks into disk groups that can then be administered as a unit.

The Sun StorEdge A3000 disk expansion unit also has the capability of mirroring, concatenation, and striping all within the Sun StorEdge A3000 hardware. You must use SSVM or CVM to manage disksets on the Sun StorEdge A3000. You also must use SSVM or CVM if you want to concatenate or stripe over several Sun StorEdge A3000s or mirror between Sun StorEdge A3000s.

For information on your particular volume manager refer to your volume manager documentation.

1.5.7.1 Disk Groups

Disk groups are sets of mirrored or RAID5 configurations composed of shared disks. All data service and parallel database data is stored in disk groups on the shared disks. Mirrors within disk groups are generally organized such that each half of a mirror is physically located within a separate disk expansion unit and connected to a separate controller or host adapter. This eliminates a single disk or disk expansion unit as a single point of failure.

Disk groups may either be used for raw data storage, or for file systems, or both.