monkey.lookup.js

var dns = require('dns');
var net = require('net');

var _lookup = dns.lookup;

dns.lookup = function(name, cb) {
  dns.resolve(name, function (err, ips) {
    if (err)
      return cb(err);
    var rand = Math.floor((Math.random() * ips.length));
    var ip = ips[rand];
    cb(null, ip, net.isIP(ip));
  });
};