Cluster Detection and Node Selection when Using Oracle DBCA

Oracle DBCA automatically shows Oracle RAC options at startup if it detects from the central Oracle Inventory that the Oracle home is enabled for Oracle RAC.

If DBCA does not automatically display Oracle RAC options, then DBCA was unable to detect if the Oracle home is installed on a cluster. In this case, perform the following steps to make the nodes visible to Oracle DBCA.

Check that the OUI inventory is correctly located in the directory /etc/oraInst.loc, and that the oraInventory file is not corrupted.
Perform Oracle Clusterware diagnostics by using the following CVU command:
```
$ /u01/app/21.0.0/grid/bin/cluvfy/cluvfy.sh stage -post crsinst -n nodelist
```
Note that when using DBCA, if nodes that are part of your cluster installation do not appear on the Node Selection page, then run the Opatch lsinventory command to perform inventory diagnostics. Also use CVU to perform clusterware diagnostics.

On the Management Options page, you are provided options for managing the database, either with Oracle Enterprise Manager Database Express or Oracle Enterprise Manager Cloud Control. For Oracle RAC databases, Oracle Enterprise Manager Database Express is configured to connect to the cluster using the Single Client Access Name (SCAN).

Parent topic: Selecting Oracle DBCA Options to Create an Oracle RAC or Oracle RAC One Node Database