Using --add-host or extra_hosts with docker-compose

Question

I am using docker-compose to run a test environment, that consists of about 5 different containers. The inter-container links and the shared volumes (volumes-from)

Answer 1

I have great news: this will be in Compose 1.3!

I'm using it in the current RC (RC1) like this:

rng:
  build: rng
  extra_hosts:
    seed: 1.2.3.4
    tree: 4.3.2.1