This topic describes how to migrate an ApsaraDB RDS for PostgreSQL instance across zones in the same region. After the migration is complete, the attributes, configuration, and endpoints of the RDS instance remain unchanged. The time that is required to complete the migration is based on the volume of data to be migrated. The migration can take a few hours.
Prerequisites
- The RDS instance runs one of the following PostgreSQL versions and RDS editions:
- PostgreSQL 10 on RDS High-availability Edition (with local SSDs)
- PostgreSQL 9.4
- The region where the RDS instance resides consists of multiple zones. For more information, see Regions and zones.
Billing
The migration is provided free of charge. This applies even if you migrate the RDS instance from one zone to multiple zones.
Precautions
- During the migration, a transient connection error of about 30 seconds will occur. Make sure that your application is configured to automatically reconnect to the RDS instance.
- After the migration, the RDS instance switches to a new VPC and VSwitch. In this case, the virtual IP addresses (VIPs) of the RDS instance change. Therefore, we recommend that you connect your application to the RDS instance by using an endpoint of the RDS instance.
- The VIP changes temporarily interrupt the connection with . You must immediately update the endpoints of the RDS instance in the console after the migration is complete.
- If the RDS instance has an ongoing Data Transmission Service (DTS) task, you must restart the task after the migration is complete.
Migration scenarios
Migration scenario | Description |
---|---|
Migration from one zone to another zone | The original zone where the RDS instance resides cannot ensure service performance due to heavy workloads or other issues. |
Migration from one zone to multiple zones | You want to achieve disaster recovery across data centers for the RDS instance. After
the migration, the RDS instance and its secondary instance reside in different zones.
Multi-zone deployment delivers higher disaster recovery capabilities than single-zone deployment. For example, RDS instances that are deployed in a single zone can withstand server and rack failures. However, RDS instances that are deployed in multiple zones can withstand data center failures. |
Migration from multiple zones to one zone | You want the RDS instance to provide specific functions that are available only for single-zone deployment. |
Procedure
Related operations
Operation | Description |
---|---|
Migration zone | Migrates an ApsaraDB for RDS instance across zones in the same region. |