For those that think IPv6 isn't out there. From the Alexa top 1M list as of 2016-12-25. 404357 zones have both IPv4 and IPv6 nameservers 548549 zones have IPv4 only nameservers 8 zones have IPv6 only nameservers the rest NS or address lookups failed for one reason or another. -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka@xxxxxxx