Source: Oracle Documentations
Guidelines for Installation of Oracle Identity Management Components Separately
1. For the same OracleAS Metadata Repository not allowed to install and configure more then one OCA against.
2. For same Oracle AS Metadata Repository allowed to install and configure more than one OracleAS Single Sign-On, Oracle Delegated Administration Services, or Oracle Directory Integration Platform.Can configure more than one Oracle Internet Directory against the same OracleAS Metadata Repository.
3. If you configure OracleAS Single Sign-On and Oracle Delegated Administration Services in separate installations against the same Oracle Internet Directory, make sure you configure OracleAS Single Sign-On before Oracle Delegated Administration Services. This is because Oracle Delegated Administration Services depends on mod_osso, which will not be set up during installation unless the Oracle Internet Directory it points to already has OracleAS Single Sign-On configured.
4. If you have an Oracle Identity Management installation that includes Oracle Directory Integration Platform but does not include Oracle Internet Directory, you will still see an Oracle Internet Directory process in the opmnctl status output. This is because oidmon must be installed and started in order to start the Oracle Directory Integration Platform process.
Special Note:1. You cannot configure Oracle Internet Directory after installation. You need to install and configure Oracle Internet Directory through the installer.
2. You can install the OracleAS Metadata Repository in a new database, or in an existing database.
3. You can use an existing Oracle Internet Directory instead of having the installer create a new one. You might want to do this if your applications need to authenticate users that are already stored in your Oracle Internet Directory. During the infrastructure installation, do not select "Oracle Internet Directory" in the Select Configuration Options screen.
You need to provide the connect information (hostname, port, username, password) for the existing Oracle Internet Directory.
The Oracle Internet Directory must be version 9.0.4 or later. Note that Oracle Internet Directory version 9.2.x is not supported.
To determine the Oracle Internet Directory version, make sure that Oracle Internet Directory is up and running. Then run the following command:
$ oidldapd -version
The oidldapd command can be found in the ORACLE_HOME/bin directory, where ORACLE_HOME is the root directory where you installed Oracle Internet Directory.
4. The OracleAS Metadata Repository and the Oracle Internet Directory work closely together. Before you can use an OracleAS Metadata Repository (in most cases), ensure that it is registered with an Oracle Internet Directory.
An exception to this rule is when you want to use a J2EE and Web Cache middle tier with the Database-Based Farm feature but without the Oracle Identity Management Access feature. In this case, you need an OracleAS Metadata Repository, but it need not be registered with an Oracle Internet Directory.