MAA Gold, based on an Oracle Active Data Guard solution with a primary and standby database, provides a number of advantages for MAA Gold.
- Improved data protection. If a primary or standby database detects a physical data corruption, Oracle can initiate auto block repair on the data corruption with zero application and database downtime. This is a major benefit to maintain data integrity and availability for all databases in an Active Data Guard environment. Furthermore, the standby database can detect lost writes and logical block corruptions, prevent logical corruptions, and provide a mechanism to fail over automatically, reducing the impact of these corruptions and downtime.
- Disaster recovery protection with reduced downtime and zero or near zero data loss from database, cluster, or site failures, application protection, and a reduced downtime and data loss solution using the standby database.
- Zero Data Loss with Maximum Availability or Maximum Protection modes with synchronous transport support. Near zero data loss with Maximum Performance with streaming ASYNC transport support.
- Bounded RTO (recovery time) and RPO (data loss) with Data Guard Fast-Start Failover. The maximum protection and maximum availability modes provide an automatic failover environment guaranteed to lose no data. Maximum performance mode provides an automatic failover environment guaranteed to lose no more than the amount of data (in seconds) specified by the
FastStartFailoverLagLimitconfiguration property. This property indicates the maximum amount of data loss that is permissible in order for an automatic failover to occur. All Data Guard Fast-Start Failover solution provides a quorum of 2 to ensure data consistency in this distributed Data Guard environment.
- Offload workload and operation from primary databases to the standby database.
- Expensive backup operations, and those respective backups can be used to restore the primary or standby databases
- Read-intensive queries and report jobs
- Testing software or hardware updates on the standby to ensure overall availability and integrity prior to applying the same changes on the primary provides additional validation besides using just test environments
- Testing with snapshot standby without sacrificing potential data loss
- Validation and early detection, prevention and auto repair of data corruptions are built-in with Active Data Guard and redo apply
- Reduce downtime for planned maintenance by implementing changes in an Oracle RAC and Data Guard rolling manner across Oracle RAC nodes or primary and standby databases. Using DBMS_ROLLING and transient logical solution, the standby can be upgraded and switched to with seconds of downtime while maintaining disaster recovery protection.
- Application Failover Best Practices or Application Continuity reduces downtime for primary database failure or complete database planned maintenance by draining and relocating connections and optionally replaying application requests at the new primary database after a Data Guard role transition. Application failover best practices recommend simple non-intrusive application changes that include using Oracle services, modifying connection strings to accommodate both primary and local standby databases, and enabling fast application notification and draining. Optionally enabling Application Continuity or Transparent Application Continuity (TAC) will require some additional application investment to reap the benefits of application replay after failure. See Continuous Availability - Application Checklist for Continuous Service for MAA Solutions for steps and guidance.
- Simplify migration to new platforms and technologies by using standby database to switch to new platform like Exadata or Exadata cloud or to enable new database options and capabilities like Transparent Data Encryption (TDE).
Optionally, you can enhance your high availability architecture by using these recommended features and capabilities:
- Global Data Services is an Oracle Database workload management solution that provides dynamic load balancing of client connections and workload requests across the replicas.
- Full Stack Disaster Recovery is an Oracle Cloud Infrastructure (OCI) disaster recovery orchestration and management service that provides comprehensive disaster recovery capabilities for all layers of an application stack, including infrastructure, middleware, database, and application.
- Select Oracle Enterprise Manager packs
To achieve an MAA Gold level of service use Oracle Active Data Guard and Oracle RAC.
Oracle Active Data Guard provides more Oracle database protection and advantages than third party replication, as shown in the following table.
| Benefits | Oracle Active Data Guard | Third Party Replication |
| Data corruption protection | Yes | No |
| Auto block repair of physical block corruptions | Yes | No |
| RTO | Seconds to 2 minutes | Up to 30 minutes |
| RPO | Zero or near zero | Zero (within region only) to near zero |
| Active standby reporting | Yes | None (additional copies required to create reporting database) |
| Network bandwidth required | Small (redo changes only) | Typical 7X bandwidth because all database, redo, temp, undo, and controlfile changes are replicated |
| Application integration | Yes (with Application Continuity) | None (needs to be customized) |
Automatic failover with quorum of 2 with Data Guard broker observers (preserves data consistency and prevents split brain primary databases) | Yes | None (needs to be customized) |
| Database rolling upgrade | Yes | No |
| Scalable reader farm while maintaining protection and disaster recovery | Yes | No |
For more information about Oracle capabilities used in this MAA reference architectures click on the objects in the graphic above.
Learn more about Oracle MAA blueprints for reduced planned and unplanned downtime for Oracle Database on-premises, on Exadata Database Machine, and on Oracle Cloud.