Oracle Clusterware provides the clustering infrastructure for Oracle Database Appliance.
Oracle Clusterware provides the cluster technology required for Oracle Real Application Clusters (Oracle RAC). In addition, Oracle Clusterware manages applications and processes as resources that you register with Oracle Clusterware, to provide high availability services. The number of resources that you register with Oracle Clusterware to manage an application depends on the application. Applications that consist of only one process are usually represented by only one resource. More complex applications that use multiple processes or components can require multiple resources to maintain high availability.
Refer to Oracle Clusterware Administration and Deployment Guide for information about making applications highly available with Oracle Clusterware.