Active Data Guard

The most reliable and secure data protection

Oracle Active Data Guard maintains an identical copy of an Oracle Database by efficiently replicating its data in memory from a fully active primary database to secondary replica databases using Oracle’s unique redo information. Transferred data is continuously validated to prevent data corruption, lost writes, and ransomware attacks. Should a data block corruption be detected in any database participating in an Active Data Guard configuration, Oracle Active Data Guard transparently replaces the damaged blocks with a non-corrupted copy from one of the other databases online. Replicas can run read-only workloads and take over the application workload from an impacted database at any time while guaranteeing data consistency and accessibility, regardless of the type of failure, outage, or network partition.

Consistent read-mostly replicas with linear scalability

Oracle Active Data Guard allows offloading read-mostly work to its replicas, freeing up valuable resources on the primary database to handle more read-write operations. Replicas provide linear scalability for intensive read workloads and occasional write workloads requiring transactional consistency with the primary database. Active Data Guard's ability to perform data modifications directly on the standby databases using DML Redirect (data manipulation language) allows applications traditionally required to connect to the primary database to work seamlessly when connected to a database replica.

Continuous application availability during Oracle Database upgrades

Oracle Active Data Guard facilitates seamless rolling database updates, including major-version upgrades, without application downtime. This ensures the continuous availability of critical databases during increasingly frequent software upgrades. Oracle Active Guard simplifies standard upgrade procedures by providing a unique automation framework that uses a replica database to protect the primary database throughout the upgrade process. This minimizes the risk of any issues or mistakes during the process and allows for an easy rollback of the upgrade if required.

Starting with Oracle Database 23ai, the same process avoids application disconnects, enabling business continuity. This is made possible by Oracle’s unique ability for database sessions to transparently restart and restore the transaction state on the new database version, masking outages from users.

Most adaptable database disaster recovery over any distance and latency

Oracle Active Data Guard provides the most flexible data replication and disaster recovery solution for Oracle Database, capable of adapting to any distance and latency requirements. Active Data Guard provides this protection by using a unique combination of asynchronous and synchronous network-based in-memory data transfer mechanisms combined with an acknowledged or trusted mode of replication and application of changes. For long distance, including intercontinental, replication hierarchical or relay-based data transfers can be enabled, and data can optionally be encrypted and compressed, ensuring data security, low latency transfer, and zero data loss guaranteed over any distance.