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

  1. Log on to the ApsaraDB for RDS console.
  2. In the left-side navigation pane, click Instances. In the top navigation bar, select the region where the target RDS instance resides.
    Select a region
  3. Find the target instance and click the instance ID.
  4. In the upper-right corner of the Basic Information section, click Migrate Across Zones.
  5. In the dialog box that appears, specify the destination zone, VSwitch, and switching time, and then click OK.

    After you click OK, the system starts to copy the data of the RDS instance to the destination zone. This does not interrupt the running of the RDS instance. After all of the data is copied to the destination zone, your workloads are switched over to the destination zone at the specified switching time (Switch Now or Switch Within Maintenance Window).

    Note
    • During the switchover, a transient connection error of about 30 seconds will occur. Make sure that your application is configured to automatically reconnect to the RDS instance. Otherwise, you must manually reconnect your application to the RDS instance.
    • If the DNS records cached on the client are not immediately updated after the migration is complete, some of your workloads may be switched over to the destination zone 10 minutes later. This will cause another transient connection error.
    Migrate Instance Across Zones

Related operations

Operation Description
Migration zone Migrates an ApsaraDB for RDS instance across zones in the same region.