The figure shows two nodes in hardware cluster. One node (cluster node 1) is active, and the other node, cluster node 2, is passive. Cluster node 1 runs Oracle BPEL Process Manager and an application server. Cluster node 2 runs the same processes, but only if cluster node 1 fails. The hardware cluster is associated with a virtual hostname and IP. During normal runtime, the virtual hostname and IP are associated with cluster node 1. On failover, the virtual hostname and IP point to cluster node 2.

Both nodes are connected to a shared storage. Normally cluster node 1 has access to it. If cluster node 1 fails, then cluster node 2 gets access to it.

These nodes use a Real Application Clusters database for the dehydration store. To run the Real Application Clusters database, there are two nodes in a cluster with a shared storage.