How the Agents for Hybrid Applications Work

The agents for hybrid applications include:

• RVG Agent
• RVGPrimary Agent

A hybrid configuration is for Replicated Data Clusters (RDCs) and is a combination of the failover and parallel service groups. A hybrid service group behaves like a failover group within a system zone and like a parallel group across system zones. It cannot fail over across system zones. A switch operation on a hybrid service group is allowed only between systems within the same system zone.

For more information about the RVG agent and RVGPrimary agent, see RVG Agent and RVGPrimary Agent respectively. These section give information about the entry points, state definitions, and attributes for the RVG agent and the RVGPrimary agent. In addition, the following attribute must be set for the RVG agent and the RVGPrimary agent while configuring RDCs:

An RDC uses VVR as opposed to shared storage to provide access to data at the Secondary. An RDC exists within a single VCS cluster. The application group, which is configured as a failover group, can be online only on the Primary host. In the case of the failure of the Primary site, the Secondary is promoted to a Primary and the application is brought online on the new Primary host.

An RDC configuration is appropriate in configurations lacking shared storage or SAN interconnection between the Primary site and Secondary site, but where dual dedicated LLT links are available between the Primary site and the Secondary site. For more information about RDCs, refer to the VERITAS Cluster Server User's Guide.