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 distributed OracleAS Cold Failover Cluster (Identity Management) topology on UNIX:
Oracle HTTP Server, OracleAS Single Sign-On, and Oracle Delegated Administration Services running on two nodes. Both of these nodes are active, and are fronted by a load balancer. This load balancer is configured with an HTTP virtual server name of "sso.mydomain.com".
This load balancer is also configured with another HTTP virtual server name of "mt.mydomain.com". Clients can use this virtual server name to access the middle tier.
Oracle Internet Directory and Oracle Directory Integration and Provisioning running on two nodes in a hardware cluster. OracleAS Metadata Repository also runs on these nodes. One of these nodes is the active node, and the other node is the passive, or standby, node. These nodes also run a vendor clusterware.
The cluster nodes are connected to a shared storage, but only one node, the active node, can mount the shared storage at any one time. The shared storage contains the Oracle homes for the OracleAS Metadata Repository database and for Oracle Identity Management. These are two separate Oracle homes.
The cluster nodes are associated with a virtual hostname ("infra.mydomain.com") and IP. Clients such as OracleAS Single Sign-On, Oracle Delegated Administration Services, and middle tiers use the virtual hostname to access the Oracle Internet Directory, Oracle Directory Integration and Provisioning, and OracleAS Metadata Repository components.