One of the fundamental issues to deal with while building out my company’s cloud deployment was the need to assign our own hostnames to our instances. To accomplish this, we needed some sort of internal dns solution. One complication we encountered was that the instances where located in different EC2 regions (EU, US and soon, a possible second US region). Each Amazon region has it’s own private class A ip range, to which the instances are NAT’d, and public class B’s.