Docs

RDS for MySQL

Managing blue-green deployment

Switching blue and green instances

After you verify the upgrades or changes in the green instance and confirm that its performance, stability, and compatibility meet the expected standards, you can perform a blue-green switch to quickly and smoothly migrate services from the blue instance to the green instance. This topic describes the steps to perform a blue-green switch.

Precautions

The blue instance and the green instance will exchange metadata and connection endpoints except for the specification configuration. During the switch, the instance may become read-only for minutes and experience multiple connection interruptions. Proceed with caution. Add a reconnection feature to your application to reduce the impact of such events on your services.

If you modify the write mode of the green instance after creating the blue-green deployment, you must rebuild the data on the green instance before the blue-green switch.

RDS for MySQL performs a pre-check on the blue-green deployment before the switch. For details about the pre-check items, refer to Check items list.

A green instance can be created for an instance with Transparent Data Encryption enabled. However, a blue-green switch is not supported because Transparent Data Encryption cannot be disabled once it is enabled.

If SSL encryption is enabled for the instance, it must be disabled before the blue-green switch.

The downtime for a blue-green switch is usually less than a minute.

Public network replication may extend the switch time due to bandwidth limitations or high latency.

The blue-green switch uses a DNS switch solution, and the IP address changes after the switch.

After a blue-green switch is executed, the synchronization link for the blue-green deployment is automatically rebuilt. If the creation fails, an InstanceBlueGreenDtsRebuildTaskFailed event is sent for the instance in the Event Center of Cloud Monitor. For more details about viewing an event, refer to Viewing an event.

Prerequisites

The blue-green deployment has been created, and the state of both the blue and green instances in the target blue-green deployment is Running. For more information, refer to Creating a blue-green deployment.

A synchronization task has been created for the blue-green deployment and its state is Executing. For more information, refer to Creating a blue-green deployment synchronization link.

The target blue-green deployment has not undergone a blue-green switch.

Procedure

Log on to the RDS for MySQL console.

In the upper-left corner of the top menu bar, select the project and region for the instance.

tip

If the project of the instance has not been set, the project should be selected as All resources.

In the left navigation bar, click Instances to view the list of RDS for MySQL instances.

On the Instances page, click the name of the target blue instance or green instance to go to the Summary tab.

Click the Connectivity tab. In the Instance topology area, click Blue-green switch from the Actions drop-down list on the Green instance card to go to the Pre-check page.

tip

When you click the Blue-green switch button, RDS for MySQL simultaneously initiates a pre-check for the blue-green deployment and displays the check results on the Blue-green switch page. If a check item fails, the check result is marked as "Failed", "Warning", or "Prompt" on the page, depending on the impact level.

After the pre-check is complete, view the pre-check results on the Pre-check page. After you resolve any issues based on the check results, click Next step to go to the Switch configuration page for the blue-green switch.

Check result	Description	Solution
Failed	The problem must be resolved or fixed before the switch. The upgrade process cannot be continued until the problem is resolved.	Click View repair suggestions and solutions to get the repair suggestions and solutions. After the fix is complete, click Re-pre-check in the lower-right corner of the Blue-green switch page to run the pre-check again.
Warning	Repair or ignore this as needed. The upgrade process cannot continue until this is ignored.	Confirm whether there is any impact or risk to your services. If there is an impact, resolve the issues for the check items that have a Failed result and run the pre-check again. If there is no impact, click Ignore in the Actions column of the check items list. tip If multiple check items have a Warning result, click Ignore all at the top of the list after confirming that there is no impact on your services.
Prompt	A prompt about the expected changes to the instance after the blue-green switch.	No action is required.

After you complete the following configurations on the Switch configuration page, click Next step to go to the Switch summary page of the blue-green switch.

Configuration item	Description
Switch time	Select the switch time. You can select Execute now, Specific time period, or Maintenance window. Switch now: Executes immediately after the upgrade order is submitted. Specific time period: Perform the specification change within the specified time period. Maintenance window: Execute within the maintenance window set for the instance. You can view the currently set maintenance window for your instance on the Summary page. To adjust, see Configuring maintenance window.
Specific time period	If you choose to upgrade within a specific time period, you must set the upgrade time period. tip Time periods cannot be set across days. The minimum time period is two hours. Set the time period within the time range indicated in the console.
Maintenance window	If you choose to upgrade within the maintenance window, you need to confirm the instance's maintenance window. tip You can click Edit to modify the maintenance window of the instance. For detailed rules on setting maintenance window, see Configuring maintenance window. After a task is initiated, you can still modify the instance's maintenance window, but the execution time of the initiated task will not be automatically adjusted with the modification of the maintenance window. If you need to adjust the execution time of a task, you need to manually schedule and adjust it at Task center. For more information about modifying tasks execution time, see Changing the execution time of a task.
Migrate endpoint	Select the connection endpoints to be retained during the blue-green switch and specify their migration relationships. After the switch is complete, the instance will use the selected connection endpoints to provide services. After you click the +Add button at the bottom of the Migrate endpoint list, you can select more custom connection endpoints from the drop-down lists for the blue and green instances and specify the migration relationship. The following rules apply when you select connection endpoints and specify migration relationships: The default endpoint of the blue instance is migrated to the default endpoint of the green instance. The number of custom connection endpoints that you can select depends on the number of custom connection endpoints in the green instance. Multi-node instances only support creating three custom read-write direct endpoints. If your green instance is a multi-node type, you can migrate only three custom endpoints from the blue instance. The source and target connection endpoints for the migration must have the same endpoint type and read/write mode. If public network resolution is enabled for the private network domain of the source connection endpoint, it is automatically enabled for the target connection endpoint after migration. Migrating connection endpoints with public network access enabled is not supported. tip Click Delete in the Actions column of the Migrate endpoint list to remove the selected custom connection endpoints.

The Switch summary page displays the following information for the blue and green instances in the blue-green deployment: compatible version, kernel version, proxy information, specification, storage, instance type, allowlists, endpoint information, endpoint information to be migrated, and parameter information. After you confirm the information, click Submit to initiate the blue-green switch.

tip

After the blue-green switch is initiated, the blue-green switch page will close, and the instance state will change to Blue-green switching. You can check the detailed progress of the upgrade task in the Task center.

Related API

API	Description
SwitchDBBlueGreen	Call the SwitchDBBlueGreen API to switch the blue-green deployment.

Last updated: 2026.05.28 15:17:54