Performing a Switchover for a Dual-AZ Task

When you create a synchronization task, you can select the DRS task type. The DRS task can be a single-AZ task or a dual-AZ task. The dual-AZ deployment provides HA, improving the reliability of DRS tasks. After a dual-AZ task is created, DRS creates two subtasks, each running in the primary and standby AZs. If the subtask in the primary AZ fails, DRS automatically starts the subtask in the standby AZ to continue the synchronization.

You can select the DRS task type in the following scenarios:

To the cloud
- MySQL->MySQL
- MySQL->GaussDB(for MySQL)
- MySQL->GaussDB(DWS)
- MySQL->MariaDB
- GaussDB(for MySQL)->GaussDB(for MySQL)
- MariaDB->MySQL
- MariaDB->GaussDB(for MySQL)
- Oracle -> GaussDB Primary/Standby
- Oracle -> GaussDB Distributed
From the cloud
- MySQL->Kafka
- MySQL->MariaDB
- GaussDB(for MySQL)->Kafka
- GaussDB(for MySQL)->CSS/ES
- GaussDB primary/standby -> Kafka
- GaussDB Distributed -> Kafka
Self-built -> Self-built
- MySQL->Kafka
- Oracle->Kafka
- Oracle -> GaussDB Primary/Standby
- Oracle -> GaussDB Distributed
- GaussDB primary/standby -> Kafka
- GaussDB Distributed -> Kafka

Prerequisites

You have logged in to the DRS console.

Scenarios

On the Data Synchronization Management page, click Create Synchronization Task.
On the Create Synchronization Instance page, configure the task name, description, and the synchronization instance details, set DRS Task Type to Dual-AZ, and click Next.
Return to the Data Synchronization Management page, you can find that there are two subtasks displayed under the synchronization task you created.

Figure 1 Primary/Standby tasks
After a synchronization task is configured and started, DRS will start the task in the primary AZ, and the task in the standby AZ is suspended.

Figure 2 Before the primary/standby switchover
If the task in the primary AZ is abnormal, DRS automatically starts the task in the standby AZ to continue the synchronization.

Figure 3 After the primary/standby switchover