Oracle Internet Directory is LDAP Compliant Directory Server from Oracle to know more about OID click here
For High Availability of OID you can configure multiple OID Server (all as single cluster) against normal database or RAC Database.
Key Points for Multiple OID Server with RAC
1. There can be one of more Directory server instance per host for high availability and repository for OID servers must be same database (This database can be plain database or RAC database)
2. OID consist of Directory Server, Integration Server and Replication Server. Directory Server is active on all nodes of OID where as Directory replication server instance is active on only one of nodes.
3. If node on which Replication server running fails, OIDMON (OID Monitor process) starts replication server on other running directory server instance.
4. LDAP Clients can connect to individual directory server (directly via hostname & port) or via Load Balancer (configure load balancer infront of directory server)
5. If you change ODS Password on one OID node using OIDPASSWD utility, then update wallet password on other OID node as well. (ORACLE_HOME/ldap/admin/oidpwdlldap1).
6. To configure OID cluster (more than one node), MR (Metadata Repository should already exist).
Install MR either selecting only MR from Identity Management (10.1.4) software runInstaller
or
Install Database first and load MR using RepCA (Repository Creation Assistance Tool)
7. For installing OID in cluster (HA), you should always select Identity Management option of Installer.
Never select “Identity Manager + Metadata repository” option.
8. During Installation, select same components (sso, oid, das..) on all nodes of Identity Management in cluster.
9. Clocks on all nodes of OID should be synced
10. Installer install & configure DIP on all nodes but starts only on first node.
11. Procedure for installing Identity Management on first node in cluster is different than installing subsequent nodes of OID.
Step by Step Installation of OID/SSO in Cluster coming soon …..