Hello Oliver, You don't need to enter anything in the NS entry on your sixxs subnet's webpage. The field is optional, and allows you to enter a dns-server to enable reverse-dns on your ipv6 addresses. (see http://en.wikipedia.org/wiki/Reverse_dns and especially the IPv6 section and the Uses section) It's not needed when you want to point your.domain.com to your ipv6 ip (hostname --> ip). You use your regular dns server for that. It works the other way around (ip --> hostname) If you want people (or computers) to know which hostname you use for a ipv6 ip, you need reverse-dns. Since the provider of the ip range needs to know which server to send the query to, you should to enter the dns-server in that box. Since sixxs only provides your ipv6 addresses, reverse-dns will only work for your ipv6 addresses. Reverse-dns for your ipv4 ip's is usually provided and locked by your ipv4 provider. Officially it's a requirement of the specs to have a reverse-dns, and one that matches 'forward'-dns so that address resolution works both ways, but imho I'd suggest you postpone that until after you actually know how and why the rest works. I've just set mine up last week. Greetings, Martijn