About Real Application Clusters
In a Real Application Clusters (RAC) environment, many Oracle database instances exist on separate servers, each with direct connectivity to a single Oracle database. All the servers can run transactions concurrently against the same database. Should any single server or instance fail, processing continues on the surviving servers.
RAC supports all Oracle backup features that are available in exclusive mode, including online backups and offline backups of an entire database or individual tablespaces.