title: How to use properly centos dockerfile with ubuntu host?
body: <p>I would like to know if it is dangerous or dumb to use a centos image with an ubuntu host.
  I understand the main concepts with Docker (lxc, aufs...) but if we start a centos container is it a real centos ? the kernel is this from ubuntu. How to deal with it ?</p>
  
  <p>Sorry if my question is bad explained.</p>
  
  <p>Thanks a lot. Best regards
  Nicolas</p>