String hostname = e.getKey();
DnsResponse response = e.getValue().sync().getNow();
assertThat(response.header().responseCode(), is(DnsResponseCode.NOERROR));
List<DnsResource> mxList = new ArrayList<DnsResource>();
for (DnsResource r: response.answers()) {
if (r.type() == DnsType.MX) {
mxList.add(r);
}
}