Migrate an instance across zones - ApsaraDB for Redis - Alibaba Cloud Documentation Center

If the current zone in which your instance is deployed has insufficient resources for a specification upgrade or if you want to improve the disaster recovery capability, you can migrate the instance to another zone.

Prerequisites

The instance uses local disks or is a standard instance that uses cloud disks. For more information, see Comparison between ApsaraDB for Redis instances that use local disks and those that use cloud disks.

The ApsaraDB for Redis instance has a classic network endpoint or a Virtual Private Cloud (VPC) endpoint, and does not have the following endpoints.

Notice If the instance has the endpoints that are listed in the following table, release the endpoints before you migrate the instance. Otherwise, the Cross-zone Migration button is dimmed and the operation cannot be performed.


Endpoint	Method to release
Classic network endpoint that is retained when the network type is changed to VPC	Release a classic network endpoint
Public endpoint	Release a public endpoint for an ApsaraDB for Redis instance
Private endpoint	Release a private endpoint for an ApsaraDB for Redis instance

Precautions

When you migrate an instance across zones, the instance may experience transient connections for a few seconds. Make sure that your application is configured with a reconnection mechanism.
The amount of time that is required for the migration varies with factors such as the network conditions, task queue state, and data volume. We recommend that you migrate the instance during off-peak hours.
If you migrate an instance across zones, the virtual IP address (VIP) of the instance is changed. Example: 172.16.88.60. However, the endpoint of the instance remains unchanged. We recommend that you connect to the instance by using the endpoint. If you use a VIP to connect to the instance, the connection fails.
If an instance is deployed in a VPC, you cannot change the VPC when you migrate the instance across zones.
To ensure better performance and stability, if the minor version of an instance is outdated, the system updates the minor version of the instance to the latest version during the migration.

Supported migration types and scenarios


Type	Scenario
Migrate an instance from one zone to another	The ApsaraDB for Redis instance is migrated to a zone where an Elastic Compute Service (ECS) instance is deployed. Then, the ECS instance can connect to the ApsaraDB for Redis instance over an internal network with lower network latency.
Migrate an instance from multiple zones to other zones
Migrate an instance from one zone to multiple zones	You want to implement disaster recovery across data centers for the ApsaraDB for Redis instance. An ApsaraDB for Redis instance that is deployed in a single zone can tolerate server- and rack-level faults. An ApsaraDB for Redis instance that is deployed in multiple zones can tolerate data center-level faults.
Migrate an instance from multiple zones to one zone	You want to migrate the ApsaraDB for Redis instance based on specific business needs.

Procedure

Log on to the ApsaraDB for Redis console and go to the Instances page. In the top navigation bar, select the region in which the instance is deployed. Then, find the instance and click its ID.
In the Basic Information section, click Cross-zone Migration.

In the panel that appears, configure the parameters described in the following table.


Parameter	Description
Destination Primary Zone	The primary destination zone to which you want to migrate the instance.
Destination Secondary Zone (optional)	The secondary destination zone to which you want to migrate the instance. If you set this parameter, the replica node of the instance is migrated to this zone. This achieves disaster recovery across zones. If the master node fails, the system fails the workloads over to the replica node in the secondary zone. This improves service continuity. However, the failover may cause cross-zone access between the instance and your other business. To resolve this issue, you must manually change the zone. Note If you do not set this parameter, both the master node and the replica node of the instance are migrated to the primary zone.
VSwitch	The destination vSwitch. If no vSwitch exists in the destination zone, you must create one. For more information, see Create and manage a vSwitch. Note This parameter is displayed only if the instance is deployed in a VPC.
Exec Time	Update Now: After you click OK, the migration immediately starts. When the instance state changes to Running, the instance is migrated. Update During Maintenance: After you click OK, the pre-migration operations immediately start and the instance state changes to Migrating to Another Zone. During this process, the instance remains fully operational. The migration starts when the maintenance window begins. During the maintenance window, the instance experiences transient connections for a few seconds. Make sure that your application is configured with a reconnection mechanism. We recommend that you set the maintenance window to off-peak hours. For more information, see and Set a maintenance window.

Read and select the check box. Then, click OK.

Related API operations


Operation	Description
MigrateToOtherZone	Migrates an ApsaraDB for Redis instance across zones within the same region.