How to autoscale Servers in ECS?

Question

I recently started using ECS. I was able to deploy a container image in ECR and create task definition for my container with CPU/Memory limits. My use case is that each container will be a long running app (no webserver, no port mapping needed). The containers will be spawned on demand 1 at a time and deleted on demand 1 at a time.

I am able to create a cluster with N server instances. But I'd like to be able for the server instances to automatically scale up/down. For example if there isn't enough CPU/Memory in the cluster, I'd like a new instance to be created.

And if there is an instance with no containers running in it, I'd like that specific instance to be scaled down / deleted. This is to avoid auto scale down termination of a server instance that has running tasks in it.

What steps are needed to be able to achieve this?

user_112821 · Answer

As part of this year's re:Invent conference, AWS announced cluster auto scaling for Amazon ECS. Clusters configured with auto scaling can now add more capacity when needed and remove capacity that is not necessary. You can find more information about this in the documentation.

However, depending on what you're trying to run, AWS Fargate could be a better option. Fargate allows you to run containers without provisioning and managing the underlying infrastructure; i.e., you don't have to deal with any EC2 instances. With Fargate, you can make an API call to run your container, the container can run, and then there's nothing to clean up once the container stops running. Fargate is billed per-second (with a 1-minute minimum) and is priced based on the amount of CPU and memory allocated (see here for details).

How to autoscale Servers in ECS?

2 Answers