HASHJOIN

However, the good news is that until above two points are addressed we have another solution - read below... Armed with knowledge we can create two Task Definitions with placementConstraints = specific AMI and then assign the desired task definition to the ECS Service. Then, automagically, ECS Agent does all the heavy lifting by effectively moving Running Tasks from one set of AMI Instances to another, draining connections and updating ELB. The best part is that we can go back and forth - effectively employing Blue/Green Deployment strategy... Here's a step by step process using AWS Console. Once you know how to do this manually - it's possible to automate it.