Server selection is optimized using randomness, feedback, and fanout. A central server maintains a vector of server selection probabilities and provides a subset of candidate servers from the vector for the client in response to receiving from a client a request for a server address to provide substantive service. An interrogating node (i.e., the client or DNS proxy) probes the candidate servers and selects a best server based on at least one criterion. The client accesses the selected server for the substantive data, and the selected server updates a counter used to keep track of the number of times the server is selected. The servers feedback the number of times selected to the central server, which, in turn, updates weightings in the vector of server selection probabilities.