I am trying to use AWS EC2 Container Service (ECS) in order to run a dockerized webdriver (Selenium) Grid. According to docker-selenium github page, we need to either add some shared memory or mount a volume to the docker container if we want to run long running tests using the chrome browser on the selenium-node-chrome image.

On my EC2 instance, when I do a

df -h

I see that /dev/shm exists and has 3.7Gb of available free space. But if I mount the volume to my chrome-node container using the -v /dev/shm:/dev/shm property, the browser is not even coming up when I run a test. But if I mount the parent /dev directory, tests seem to run for a few seconds and then I get the "Unable to reach Browser exception" because the browser is then getting closed (I was able to confirm this through VNC Viewer). This makes me realize that mounting a volume through ECS interface / api is not gonna help.

If I directly start docker without going through the ECS route by passing the --shm-size property like

docker run --shm-size=2500m ....

The tests seem to run without any trouble.

But, ECS clearly does not support the --shm-size property as of now. So how to fix or work around this issue and still use ECS to pass the --shm-size property? Is avoiding the usage of ECS the only way here or is there any other better way?