RDS Blue/Green Deployment feature offered by AWS creates a new Staging/Green cluster from the current Production/Blue cluster. Staging/Green cluster stays in sync with Production cluster using logical replication.

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AWS RDS Blue/Green Deployment for Aurora allows for seamless database upgrades with minimal downtime by creating a new staging environment that mirrors the production environment. This method involves setting up a Green cluster that stays in sync with the Blue (current production) cluster using logical replication. During the upgrade window, a switchover is executed, making the Green cluster the new production environment with less than a minute of downtime. The process includes creating, verifying, switching over, and eventually deleting the old Blue cluster, all using Terraform scripts.

AWS RDS Blue/Green Deployment for Aurora using Terraform

Upgrade AWS RDS Major Version for Aurora DB cluster using Blue/Green Deployment