The figure shows the configuration before and after the transformation. The left side of the figure shows the non-high availability topology. It consists of a middle tier, an Oracle Identity Management instance, and an OracleAS Metadata Repository running in a single-instance database.
The right side of the figure shows the OracleAS Cluster (Identity Management) topology. In this topology, there are two Oracle Identity Management instances (one of which is from the non-high availability topology), and these instances are fronted by a load balancer. The load balancer is configured with two virtual server names: oid.mydomain.com and sso.mydomain.com. The middle tier accesses these Oracle Identity Management instances through the load balancer.
The Oracle Identity Management instances use the OracleAS Metadata Repository, which has been transformed into a Real Application Clusters database. There are two nodes in the Real Application Clusters. The Oracle home for the database is located on the local storage of each node, and the data files for the database are located on a shared storage.