Ontologies provide a means of modelling and representing a knowledge domain. Such representation, already used in purpose-built distributed information systems, can also be of great value when applied to existing distributed information systems. The domain name system (DNS) provides a wide-area distributed name resolution system which is used extensively across the Internet. Changing the type and nature of resource records stored in the DNS currently requires an extensive request for comment procedure which takes a substantial amount of time, as the change has to be made globally. We propose an ontology for a DNS zone file, to provide a machine readable codification of the DNS and a mechanism for allowing local changes to the stored and represented structure of DNS records, using the extensible nature of OWL to allow local variations without having to go through the manual RFC procedure. This ontologically based system replaces a slow manual procedure with a rapid, machine-realisable procedure based on a uniform ontological representation of significant DNS knowledge. This paper discusses the application of ontologies to the DNS and how such an application can be built using OWL, the Web ontology language