The figure shows clients connecting to a hardware cluster through a virtual hostname/virtual IP. The hardware cluster contains two nodes: an active node and a passive node. Each node runs OC4J_FED, Oracle HTTP Server, and vendor clusterware.
The virtual hostname/IP connects to the active node in the hardware cluster. On failover, it connects to the passive node.
The active node connects to a shared storage, which contains the Oracle home for Oracle Identity Federation. The passive node connects to the same shared storage on failover.
On Windows, for vendor clusterware, you need Microsoft Cluster Server and Oracle Fail Safe.
The hostnames and IP addresses for the virtual hostname, virtual IP, active node, and passive node are all different.