Recommendations

To determine whether to create SUNW.HAStorage resources within a data service resource group, consider the following criteria:

• In cases where a data service resource group has a node list in which some of the nodes are not directly connected to the storage, you must configure SUNW.HAStorage resources in the resource group and set the dependency of the other data service resources to SUNW.HAStorage. This requirement is to coordinate the boot order between the storage and the data services.

• If your data service is disk-intensive, such as Sun Cluster HA for Oracle and Sun Cluster HA for NFS, then we recommend that you add a SUNW.HAStorage resource to your data service resource group, set the dependency of your data service resources to the SUNW.HAStorage resource, and set AffinityOn to True. That way, the resource groups and disk device groups are colocated on the same node. On the other hand, if your data service is not disk-intensive-such as one that reads all its files at startup (for example, Sun Cluster HA for DNS), configuring SUNW.HAStorage is optional.

• If your cluster contains only two nodes, configuring SUNW.HAStorage is optional. However, if you plan to add nodes and run scalable services later on, you must configure SUNW.HAStorage at that time. To get prepared, you can go ahead and set up SUNW.HAStorage now and add nodes to the node list later.

See the individual chapters on data services in this document for specific recommendations.

For the procedure on how to set up SUNW.HAStorage, see "How to Set Up SUNW.HAStorage Resource Type for New Resources". Additional details are in the SUNW.HAStorage(5) man page.