AWS ECS – How to Fix Fargate Task Not Pulling Secrets from SSM

The log message you included is not the reason your task did not continue to run. What has happened is ECS launched your container with the command and parameters you specified, but the container exited on it's own. This can be difficult to debug.

It would be helpful to find the logs for the containers which have stopped. You can view all containers, including stopped containers using docker ps -a. When you have located a stopped container, you can view it's logs with docker logs <container_id>, assuming you are using the default logging driver.

For most cases, you most likely want to use an ALB/NLB for service discovery. While there are some costs, you also get a lot of benefits: Some DoS protection, scaling metrics, logging, SSL/TLS

However, you can use ECS service discovery.

Service discovery uses Amazon Route 53 auto naming API actions to manage DNS entries for your service's tasks, making them discoverable within your VPC

and

Public namespaces are supported but you must have an existing public hosted zone registered with Route 53 before creating your service discovery service.

Service discovery requires that tasks use either the awsvpc, bridge, or host network mode.

Here is a Blog entry detailing how to use Service discovery with fargate: https://aws.amazon.com/blogs/aws/amazon-ecs-service-discovery/