title: What is the purpose of the "ipam" key in a Docker Compose config?
body: <p>I am new to Docker but not so new I don't understand the cli of Docker. However I am very new to the Docker file and Docker Compose way of doing things. If someone could explain to me this section of the docker-compose.yml I would greatly appreciate it.</p>
  
  <p>My comments are embedded:</p>
  
  <pre><code>networks:
    vpcbr: &lt;-I know what this is
      driver: bridge &lt;-I know what this is
      ipam:  &lt;-What the heck is this for?
       config: &lt;-I know what this is.
         - subnet: 10.5.0.0/16 &lt;- Obvious
           gateway: 10.5.0.1 &lt;- Obvious
  </code></pre>