Failover

Failover is initiated when a serious problem exists on the primary database, making it inaccessible. This problem generally arises from hardware or software errors on the server or storage layer; also, a disaster may cause complete or partial loss of services. In such cases, we can convert a standby database role to primary by performing failover and continue providing it with production database service. Performing a Data Guard failover operation for production purposes is a serious consideration and needs a lot of caution. The following considerations are important in this context:

• Failover decision must be taken with regard to the service Recovery Time Objective (RTO) value.

• The standby database hardware must be powerful enough to sustain production load.

• Multiple standby databases are recommended; this is so that data protection continues after a failover operation.

• If the flashback database is not enabled on the primary database, after a failover it's not possible to include the...