title: 2 Docker environments in same VPC
body: <p>I am trying to contain my dev &amp; qa environment in same vpc. I have created separate overlay networks named:</p>
  
  <ul>
  <li>qa</li>
  <li>dev</li>
  </ul>
  
  <p>My dev env is up and running smoothly. I am using same container names for qa env also.</p>
  
  <p>When I try to register my container to swarm it is complaining this:</p>
  
  <pre><code>docker: Error response from daemon: Conflict: The name mongo2 is already assigned. You have to delete (or rename) that container to be able to assign mongo2 to a container again..
  </code></pre>
  
  <p>What should I do in this case.</p>
  
  <p><strong>Note:</strong> docker0 of both environments on which swarm manger is running have same subnet mask.</p>