Failover Data Services

If the node or zone on which the data service is running (the primary node) fails, the service is migrated to another working node or zone without user intervention. Failover services use a failover resource group, which is a container for application instance resources and network resources (logical host names). Logical host names are IP addresses that can be configured on one node or zone, and at a later time, automatically configured down on the original node or zone and configured on another node or zone.

For failover data services, application instances run only on a single node or zone. If the fault monitor detects an error, it either attempts to restart the instance on the same node or zone, or to start the instance on another node or zone (failover). The outcome depends on how you have configured the data service.