Some data services, such as Sun Cluster HA for Oracle and Sun Cluster HA for NFS are disk intensive. If your data service is disk intensive, ensure that the resource groups and disk device groups are colocated on the same node. To meet this requirement, perform the following tasks.
Adding an HAStorage or HAStoragePlus resource to your data service resource group
Switching the HAStorage or HAStoragePlus resource online
Setting the dependency of your data service resources to the HAStorage resource or HAStoragePlus resource
Setting AffinityOn to True
The failback settings must be identical for both the resource group and device groups.
Some data services are not disk intensive. For example, Sun Cluster HA for DNS, which reads all of its files at startup, is not disk intensive. If your data service is not disk intensive, configuring the HAStorage resource type or HAStoragePlus resource type is optional.