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This might sound like a stupid question as I have a very basic grasp of DNS management, but I'm looking for a new VPS and most providers only offer one IPV4 address, which doesn't validate on http://dnscheck.pingdom.com/.

Most VPS providers however offer "unlimited IPV6 IP addresses", so my question is - can I use IPV6 addresses instead of IPV4 for the NS1.mywebsite.com and NS2.mywebsite.com? And if yes, how exactly can this be achieved?

Thanks in advance for any replies

Dan
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Yes, you can, if your registrar supports IPv6 glue records.

However, if you're only delegating to the IPv6 record, then IPv4-only clients can't query your server. Probably an unwise decision at this point in the world's deployment of IPv6.

Anyway, all this does is circumvent that pingdom tool's check on having two name servers. The reason that check exists is to ensure that you're providing redundancy for your domain's name resolution. If you're just running on a single server, then you don't provide any extra redundancy - the 'approval' by that tool is completely irrelevant.

If you need redundant DNS resolution, don't hack around it; your registrar probably offers a DNS service that will work just fine.

Shane Madden
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  • A valid reason for having 2 or more DNS server is that some TLDs have this as a requirement (.de for example) – faker Jul 03 '12 at 22:47
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    Alternatively, if you really do want to run your own DNS server, there are plenty of services offering DNS slaves. – andol Jul 04 '12 at 00:49
  • @andol can you suggest a service for me to look into, thanks. – Dan Jul 04 '12 at 10:19
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    Multiple DNS servers is required by RFC, and it has benefits even in single-server installations. Online services offering secondary DNS for free are: [BuddyNS](http://www.buddyns.com), [Afraid](http://freedns.afraid.org/) and [Twisted4Life](http://www.twisted4life.com/). – michele Jul 04 '12 at 23:41
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can I use IPV6 addresses instead of IPV4 for the NS1.mywebsite.com and NS2.mywebsite.com?

Today, the answer is sadly no. :(

Many recursive DNS resolver do not have IPv6 connectivity and cannot communicate with an IPv6-only name server.

Example: my ISP

My ISP (Free SAS/Proxad) provides direct IPv6 access for all almost subscribers (and the few other subscribers can have IPv6 if they know how to do 6to4rd). I have tested my ISP DNS recursive resolver, and they can access IPv6-only NS. But other clients of that same ISP (Free/Proxad) have done the exact same test, and the Free/Proxad DNS recursive resolver they are using (with the same IP address I am using) lacks this IPv6 connectivity.

Conclusion: even if you believe that your ISP handles IPv6 NS just fine because you have checked that yourself, you may be wrong.

Public DNS resolvers

I have tested some public DNS resolvers, and they cannot resolve on IPv6.

Do not confuse AAAA handling with IPv6-only NS

All these DNS resolvers have no problems with the handling of AAAA records.

curiousguy
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