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. This operation does not affect the services running on the primary DB instance.
• 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 and standby DB instances in different AZs for high availability and disaster recovery.

Precautions

RDS single DB instances can be changed to primary/standby DB instances, but not the other way around. You can use Data Replication Service (DRS) or the export and import tool of the client to migrate data from primary/standby DB instances to single DB instances.

Procedure

1. Log in to the management console.
2. Click in the upper left corner and select a region and a project.
3. Click in the upper left corner of the page and choose Databases > Relational Database Service.
4. On the Instances page, locate a single 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 the instance type from single to primary/standby.

5. Select a standby AZ and enter the original administrator password. Other configurations are the same as those of the primary DB instance by default. Confirm the configurations and click Submit.
6. Check the instance status on the Instances 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.