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

https://docs.docker.com/compose/compose-file/#extra_hosts

extra_hosts - Add hostname mappings. Uses the same values as the docker client --add-host parameter.

extra_hosts:
 - "somehost:162.242.195.82"
 - "otherhost:50.31.209.229"

An entry with the ip address and hostname will be created in /etc/hosts > inside containers for this service, e.g:

162.242.195.82  somehost
50.31.209.229   otherhost