Tessell supports active standby Oracle database configurations spanning Azure availability zones for high availability using Oracle Data Guard. The benefit of this architectural approach lies in the shared-nothing architecture. Both the active and standby instances have independent storage as well as independently running Oracle database instances. Connection pooling is provided through a database proxy, so in the event of a primary database failure, client connections transparently fail over to the standby database instance.
Availability can be further enhanced by replicating data across Azure data center regions to the disaster recovery (DR) instance. The benefit of this approach is that if an entire region fails due to a natural or man-made catastrophe, a global IP failover can take place, redirecting traffic to the DR instance.