title: Issue with docker compose db2-express c
body: <p>I'm trying to set up an environment for developing my projects. I need a websphere container and a db2 container.
  I commit my own version of the containers in my repo, now using a single command docker-compose up I would like to start the entire environment.
  My docker-compose.yml is</p>
  
  <pre><code>version: '2'
  services:
   web:
    image: &lt;my_user&gt;/websphere-liberty-of-mine
    ports:
    - "80:9080"
    - "443:9443"
   db:
    image: &lt;my_user&gt;/db2-of-mine
    ports:
    - "50000:50000"
   environment:
   - DB2INST1_PASSWORD=***
   - LICENSE=accept
  </code></pre>
  
  <p>The web container starts and stay running correclty, instead db DB2 container starts and immediately stops, the message is:</p>
  
  <pre><code>Changing password for user db2inst1.
  passwd: all authentication tokens updated successfully.
  New password: Retype new password:
  </code></pre>
  
  <p>How to start alse the db DB2 container normally?<br/>
  Furthermore how can I explitely set up network and IP addresses for the two containers if my docker-compose version is</p>
  
  <pre><code>$ docker-compose version
  docker-compose version 1.7.1, build 0a9ab35
  docker-py version: 1.8.1
  CPython version: 2.7.11
  OpenSSL version: OpenSSL 1.0.2d 9 Jul 2015
  </code></pre>