You can migrate an ApsaraDB RDS for PostgreSQL instance to another zone within the same region. After the migration, the attributes, configuration, and endpoints of the instance remain unchanged. The migration may take several hours, depending on the volume of data to be migrated.

Migration types

Migration type Scenario
Migration from one zone to another 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 instances. After the migration, your primary and secondary instances are deployed in different zones.

Multi-zone deployment delivers higher disaster recovery capabilities than single-zone deployment. For example, instances deployed in a single zone can withstand server and rack faults, whereas instances deployed in multiple zones can withstand data center faults.

Migration from multiple zones to one zone You can perform this type of migration to meet specific business requirements.

Fees

The migration is free of charge even if you migrate RDS instances from one zone to multiple zones.

Prerequisites

  • Cross-zone migration is available only when the region where the instance resides has multiple zones. For more information, see Regions and zones.
  • 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

Precautions

Services may be briefly disconnected for 30 seconds during cross-zone migration, and most database, account, and network operations cannot be performed. Therefore, make sure that your application is configured to automatically reconnect to the instance and migrate the instance during off-peak hours.

Procedure

  1. Log on to the ApsaraDB for RDS console.
  2. In the top navigation bar, select the region where the target RDS instance resides.
  3. Find the target RDS instance and click its ID.
  4. In the upper-right corner of the Basic Information section, click Migrate Across Zones.
  5. In the Migrate Instance Across Zones dialog box, select the destination zone, VSwitch, and migration time. Then, click OK.

    After you click OK, the system starts to copy data to the destination zone. This does not affect the running of the instance. After the data is copied, services are switched to the new zone at the specified time (Switch Now or Switch Within Maintenance Window).

    Note
    • The services are briefly disconnected for 30 seconds during the switchover. Make sure that your application is configured to automatically reconnect to the instance. Otherwise, you must manually reconnect the application to the instance.
    • Some services may be switched 10 minutes later because the DNS cache is not flushed. This causes a brief disconnection again.
    • If you want to change the maintenance window, perform the following operations:
      1. Click Change.
      2. In the Configuration Information section, select a maintenance window and click Save.
      3. Refresh the page and perform Step 5 again.

Related operations

Operation Description
MigrateToOtherZone Migrates an RDS instance from one zone to another.