add entry to host /etc/hosts file when a docker container is started

Question

I want to be able to add hostnames to my laptop /etc/hosts that maps to a docker container. Since container ips are not static, each site I start/restart a container I would need to update the /etc/hosts file manually which is not very practical.

I am looking for a simple way to solve this. I could do some sort of script, which listens to docker events, checks for container ip and updates /etc/hosts but I dont want to reinvent the wheel. (something like this: https://github.com/discordianfish/docker-spotter) but I couldnt really understand how it works.

Anybody has a suggestion?. Thank you.

Answer 1

You can do that using in your docker-compose.yml using extra_hosts. For instance:

version: '2'
services:
  daemon:
    build: ./
    extra_hosts:
      - "example.com:127.0.0.1"