Oracle Real Application Clusters (RAC) is an option for the Oracle Database software produced by Oracle Corporation and introduced in 2001 with Oracle9i. It provides software for clustering and high availability in Oracle database environments. Oracle RAC allows multiple computers to run Oracle RDBMS software simultaneously while accessing a single database, thus providing clustering. The main aim of Oracle RAC is to implement a clustered database to provide performance, scalability, and resilience & high availability of data at the instance level.

Oracle RAC depends on the infrastructure component Oracle Clusterware to coordinate multiple servers and their sharing of data storage. The FAN (Fast Application Notification) technology detects down-states. RAC administrators can use the srvctl tool to manage RAC configurations, Cache Fusion.

Oracle RAC provides the highest database availability by removing individual database servers as a single point of failure. It enables multiple instances of the same database to run on different servers, known as nodes, in a cluster. Distributing transactions and queries across all nodes improves reliability and performance. Furthermore, it can help reduce downtime by utilizing fault tolerance mechanisms to ensure that if one node fails, another will take its place without interruption in service.

Oracle RAC is a valuable resource for any organization looking to build a dependable, scalable database architecture capable of handling mission-critical applications with minimal downtime or disruption. Oracle RAC ensures maximum performance while minimizing resource utilization, allowing businesses to focus on what matters most rather than worrying about their data.