If you are configuring a collector for Oracle RAC, you only need to configure one collector for the entire cluster. You can choose any node in the cluster to connect to, and the entire cluster is automatically detected.

If you have sub-collectors, it will disable automatic cluster discovery.

When the Database Visibility collector connects to the hostname or IP address defined in the collector configuration, it auto-discovers the RAC instance. Once a successful connection is made to a node within the RAC, then a query on GV$INSTANCE Topology Window.

When monitoring Oracle RAC, the Controller displays the aggregate data for the entire cluster.