Blue Green Deployment with AWS ECS

Question

We are using ECS Fargate containers to deploy all of our services (~10) and want to follow Blue/Green Deployment.

We have deployed all the services under BLUE flag where target groups are pointing to the services.
In CICD, New Target groups are created and having slightly different forward rules to allow testing without any issue.
Now, my System is running with 2 kind of target groups, services and task definition -

• tg_blue, service_blue, task_blue → pointing to old containers and serving live traffic
• tg_green, service_green, task_green → pointing to new containers and do not have any traffic.
  All above steps are done in Terraform.

Now, I want to switch the traffic and here I am stuck, How to Switch the Traffic and How the next Deployment will look like?

Answer 1

I would go for AWS native solution if no important reasons against. I have on my mind CodeDeploy. It switches in automatic way between TGroups. Without CDeploy, you need to implement weighted balancing among two TGroups and adjust them later on. That is extra work. Whole flow is quite good explained on this YT video.