Disk Device Groups

Add this planning information to the "Disk Device Group Configurations Worksheet" in the Sun Cluster 3.0 U1 Release Notes.

You must configure all volume manager disk groups as Sun Cluster disk device groups. This configuration enables a secondary node to host multihost disks if the primary node fails. Consider the following points when you plan disk device groups.

• Failover - You can configure multiported disks and properly-configured volume manager devices as failover devices. Proper configuration of a volume manager device includes multiported disks and correct setup of the volume manager itself so that multiple nodes can host the exported device. You cannot configure tape drives, CD-ROMs, or single-ported disks as failover devices.

• Mirroring - You must mirror the disks to protect the data from disk failure. See "Mirroring Guidelines" for additional guidelines. See "Installing and Configuring Solstice DiskSuite Software" or "Installing and Configuring VxVM Software" and your volume manager documentation for instructions on mirroring.

For more information about disk device groups, see Sun Cluster 3.0 U1 Concepts.