title: Use a single VM with Vagrant to host Docker Containers across multiple projects
body: <p>I have two separate projects/src/code repos, using Vagrant to run an application in docker containers. </p>
  
  <p>I am using Vagrant with a CentOS7 Host VM to host docker containers (<a href="https://www.vagrantup.com/docs/docker/basics.html" rel="nofollow noreferrer">https://www.vagrantup.com/docs/docker/basics.html</a>). I am using a duplicate copy of the CentOS7 VM Vagrantfile (<code>Vagranfile.host</code>) in each project. </p>
  
  <pre><code>- proj1/
  -- Vagrantfile
  -- Vagrantfile.host
  - proj2/
  -- Vagrantfile
  -- Vagrantfile.host
  </code></pre>
  
  <p>Each <code>Vagrantfile</code> points to <code>Vagrantfile.host</code> to spin up a CentOS VM to host the Docker containers.</p>
  
  <p>The only difference (effectively for this question) between the two projects is that the <code>Vagrantfile</code> in <code>proj1</code> points to a different docker image than the one in <code>proj2</code>.</p>
  
  <p>When I do <code>vagrant up</code> in each project folder, each one create's it's own CentOS7 VM instantiation, so I end up running two separate VirtualBox VMs. </p>
  
  <p>Is there a way to change one or both of the <code>Vagrantfile</code> files so that I end up only spinning up a single VM, and the containers both run in the same VirtualBox VM?</p>