OpenStack has been in a production environment at CERN for more than a year. One of the people that has been key to implementing the OpenStack infrastructure is Tim Bell. He is responsible for the CERN IT Operating Systems and Infrastructure group which provides a set of services to CERN users from email, web, operating systems, and the Infrastructure-as-a-Service cloud based on OpenStack. We had a chance to interview Bell in advance of the OpenStack Summit Paris 2014 where he will deliver two talks. The first session is about cloud federation while the second session is about multi-cell OpenStack.