Oracle Real Application Clusters (RAC) harnesses the processing power of multiple, interconnected servers on a cluster; allows access to a single database from multiple servers on a cluster, insulating both applications and database users from server failures, while providing performance that scales out on-demand at low cost; and is a vital component of grid computing that allows multiple servers to access a single database at one time. Oracle Database 11g also includes Automated Storage Management (ASM) and Oracle Clusterware. Combining the use of ASM and Oracle Clusterware virtualizes storage, database servers, application servers, holistic management, and all the other aspects.
