增加AWS ECS任务定义保留端口限制

Question

I'm trying to set up a docker container with aws' ecs service. I would like to reserve ports 30000 - 60000 on the host machine and map those ports to 30000 - 60000 on the container. Aws documentation, however, states that only 100 ports may be reserved on the host:

http://docs.aws.amazon.com/AmazonECS/latest/developerguide/task_definition_parameters.html

Can anyone explain why there's a limit/suggest workarounds?

Answer 1

I'm pretty sure the 100 port limit will be due to the way Docker maps ports .

Docker launches a Go process per mapped port which will use from 4-6MB of private memory. So at 100 ports, the Docker processes will be consuming around 500MB of memory.

If you were to try and map all 30000 - 60000 port to a container you would need ~ 150GB of memory. 300GB if you want both UDP and TCP.

If you have to use that many ports then you need to start looking at using --net=host , bridging or mapping interfaces directly into a container. This is unlikely to be supported by ECS (On EC2, I had to take the "real" MAC address from a VPC interface and put it on the containers interface ).