This presentation describes a method of building multi-host clusters for DNS service using free software. Services are provided on two more hosts, and reachability to a service address is signalled to the rest of the network from each server. In this way the service is anycast within an OSPF area. The F root nameserver is operated by ISC using nameserver clusters constructed in this manner. Issues of service monitoring, troubleshooting, stateful (TCP) transactions and necessarily-unicast, administrative functions (zone transfers, system maintenance) are discussed in some detail. The limitations of the technique with respect to load balancing, the use of other (non-DNS) protocols and operational deployment are also described.