Changing a DB Instance Type from Single to Primary/Standby

Scenarios

• RDS enables you to change single DB instances to primary/standby DB instances to improve instance reliability.
• Primary/standby DB instances support automatic failover. If the primary DB instance fails, the standby DB instance takes over services quickly. You are advised to deploy primary/standby DB instances in different AZs for high availability and disaster recovery.
• Anti-affinity deployment is supported for primary/standby DB instances to prevent the entire instance unavailability due to the failure of a single host.

Procedure

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click Service List. Under Database, click Relational Database Service. The RDS console is displayed.
4. On the Instance Management page, locate the target DB instance and choose More > Change Type to Primary/Standby in the Operation column.

   Alternatively, click the target DB instance. In the DB instance topology, click on the left to change type from single to primary/standby.

5. Select a standby AZ. Other configurations are the same as those of the primary DB instance by default. Confirm the configurations and click Submit.
6. After a single DB instance is changed to primary/standby instances, you can view and manage it on the Instance Management page.
   • The DB instance is in the Changing type to primary/standby status. You can view the progress on the Task Center page. For details, see Task Center.
   • In the upper right corner of the DB instance list, click to refresh the list. After the DB instance type is changed to primary/standby, the instance status will change to Available and the instance type will change to Primary/Standby.