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Has anybody got a list of all TLD's which require and only allow nameservers with TCP enabled?

Our ISP who provides our nameservers, only supports adding domains for UDP answers to their nameservers, so would be good to know which TLD's I cant use their nameservers for.

e.g. for French domain name nameserver hosting the following applies (and im sure ive seen it for others such) I just want a complete list of all TLDs which this is the case for;

AFNIC (the sole registrar of .fr domains) requires a nameserver query (via TCP port 53) prior >to pointing the nameservers. This is an unfortunate situation which is unique to AFNIC.

So while I appreciate that Chris's answer maybe technically correct, in practice it not the whole story.

slhck
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leenix
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1 Answers1

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Erm, disallowing TCP DNS is against the RFC. If your ISP doesn't allow TCP DNS resolution, use one of the publicly available DNS resolver services.

To directly answer your question, TCP is used by DNS when the "answer" doesn't fit in a UDP packet, and also for various server to server communication. It has nothing to do with the TLD.

Chris S
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