How to migrate Aurora Serverless V1 cluster to V2 which is already using Data API with minimal downtime?

To migrate your Aurora Serverless v1 cluster to v2 with minimal downtime while using Data API, you can follow a modified approach that addresses the issue with Data API compatibility. Here's a recommended process:

1. Start by creating a blue/green deployment of your existing Aurora Serverless v1 cluster. This allows you to upgrade the engine version without affecting the original cluster.

2. In the green environment, upgrade the Aurora MySQL version to one that supports both Aurora Serverless v2 and Data API (version 3.02.0 or later).

3. Add an Aurora Serverless v2 reader instance to the green cluster using the db.serverless instance class.

4. Enable Data API on the green cluster. This ensures that the Data API functionality is available on the new cluster before you switch over.

5. Perform a failover to promote the Aurora Serverless v2 reader to a writer instance.

6. Test the green environment thoroughly to ensure all functionality, including Data API, works as expected.

7. Once you're satisfied with the testing, switch over your application to use the green environment. This can be done by updating the endpoint in your application or by using Amazon Route 53 to update DNS records if you're using custom domain names.

8. After the switchover, you can delete the blue/green deployment resources.

This approach allows you to maintain Data API functionality throughout the migration process and minimizes downtime. The blue/green deployment strategy ensures that your original cluster remains operational until you're ready to switch, and you can keep using the same credentials stored in Secrets Manager.

It's important to note that while this process aims to minimize downtime, there may still be a brief interruption during the final switchover. However, this downtime should be significantly less than converting the original cluster from Serverless v1 to provisioned and then to Serverless v2.

Remember to thoroughly test your application with the new Aurora Serverless v2 cluster before the final switchover to ensure compatibility and optimal performance.
Sources
Migrate Aurora Serverless v1 cluster to v2 | AWS re:Post
Migrating to Aurora Serverless v2 - Amazon Aurora
Introducing the Data API for Amazon Aurora Serverless v2 and Amazon Aurora provisioned clusters | AWS Database Blog