Planned Switchover
An Oracle database operates in one of two roles: primary or standby. Data Guard helps you change the role of a database using either a switchover or a failover:
- A switchover is a role reversal between the primary database and one of its standby databases. A switchover guarantees no data loss and is typically done for planned maintenance of the primary system. During a switchover, the primary database transitions to a standby role, and the standby database transitions to the primary role.
- A failover is done when the primary database (all instances of an Oracle RAC primary database) fails or has become unreachable and one of the standby databases is transitioned to take over the primary role. Failover may or may not result in data loss depending on the protection mode in effect at the time of the failover.
Switch the Primary Database From On-Premises to OCI
When you have a planned activity, such as maintenance, you can make the database in Oracle Cloud Infrastructure (OCI) the primary database with zero data loss. A switchover is a planned event that's initiated on the on-premises database and completed on the database instance in the cloud.
Switch the Primary Database Back From OCI to On-Premises
After making the database instance in Oracle Cloud Infrastructure (OCI) the primary database, use the Oracle Data Guard command-line interface (DGMGRL) on the OCI database instance inOracle Database Exadata Cloud Service to switch back and make your on-premises database your primary database again.
You can switch the primary database back and forth between the on-premises database and the Oracle Database Exadata Cloud Service (OCI) database instance.