The figure shows two hardware clusters. Each hardware cluster consists of:

• two nodes (an active node and a passive node)

• a shared storage

• a virtual hostname and IP address

• vendor clusterware for each node. On Windows, you need Microsoft Cluster Server and Oracle Fail Safe.

In the first hardware cluster, the active node runs Oracle HTTP Server. The Oracle home for the Oracle HTTP Server is installed on the shared storage. If the active node fails, the passive node takes over, mounts the shared storage, and runs Oracle HTTP Server.

In the second hardware cluster, the active node runs OC4J_WebCenter and OC4J_Content. These components are installed on the shared storage, but in separate Oracle homes. If the active node fails, the passive node takes over, mounts the shared storage, and runs the OC4J processes. The Oracle HTTP Server that is installed in the same Oracle home as Oracle Content DB is disabled. The shared storage also contains the MDS directory.

Oracle HTTP Server in the first hardware cluster accesses the OC4J components in the second hardware cluster using the second hardware cluster's virtual hostname and IP address.

OC4J_Content connects to a cold failover cluster or Real Application Clusters database.