Fail to register container instances when creating cluster in ECS with existing ASG

Question

When I createing my cluster in ECS, the created cluster is failed to register container instance, what are the possible causes for the problem and what should I check for?
(PS: I have created a cluster with the same setting before and it works, but after I delete the cluster and re-create one, it fail to register the container instance )

Shahad_C · Answer

Does the new cluster in ECS have *exactly* the same name?  Have any changes been made to the ASG (I assume you're using one based on the question tags)?

Instances are registered to the cluster via the ECS agent on boot based on the Userdata injecting the cluster name to the ECS config: https://docs.aws.amazon.com/AmazonECS/latest/developerguide/bootstrap_container_instance.html#bootstrap_container_agent

Fail to register container instances when creating cluster in ECS with existing ASG

Relevant content