Due to interdependency between the Oracle Real Application Clusters and Oracle Database patterns, you might need to run two scans of the related hosts to discover all components of the deployment.
Oracle Real Application Clusters (RAC) is an option to the Oracle Database Enterprise Edition. Oracle RAC is a cluster database with a shared cache architecture that overcomes the limitations of traditional shared-nothing and shared-disk approaches to provide highly scalable and available database solutions for all your business applications.
Oracle's RAC option supports the transparent deployment of a single database across a cluster of servers, providing fault tolerance from hardware failures or planned outages.
Oracle Database 11g includes Oracle Clusterware, a complete, integrated clusterware management solution available on all Oracle Database 11g platforms (excluding OS/390). With Real Application Clusters, Oracle Clusterware automatically manages all Oracle processes.