Hi, > ISP 1# traceroute ns33.domaincontrol.com Have you tried ?: $ traceroute --back ns33.domaincontrol.com (might show you asymetric routing, which it probably will, as I've seen it at several hops) $ dig +dnssec +norec @ns33.domaincontrol.com replacementservices.com. a $ dig +dnssec +tcp +norec @ns33.domaincontrol.com replacementservices.com. a $ traceroute -T -p 53 ns33.domaincontrol.com $ mtr ns33.domaincontrol.com Maybe it will tell you more of what is going on. But don't expect miracles.