Updating Cloudformation Stack with ECS Task Definition and Service results in hung stack

Question

Im having a repeated issue when i run Update Stack on a Cloudformation stack consisting of ECS resources such as Task Definition and Service, the Stack hangs and cannot be killed until it times out altogether.

I am simply updating the Task with a new Tag of the Container Image, but it just hangs after running for a few minutes, and the updated Task never gets added to the Service.

Any ideas? Is this a bug in ECS?

EDIT - @wjordan here is the cloudformation template: https://s3.amazonaws.com/rga-g1-public/ops/cfn/templates/ecs-cluster-asg-elb-cfn.yaml

@GigaPalmer I added DeployConfiguration to the Service Resource with maxpercentage as 200 and min set to 50, but that did not fix the issue either.

The initial build of the stack always works correctly, but as soon as i trigger an update it seems to fail 3 out of 4 times, all of which end up with a hung stack in UPDATE mode.

Answer 1

Looks like the issue here was in the app itself. We had a python process running under PM2 that would end up as a stuck process and ECS was unable to determine the health of the service.

This issue can be closed.