I'm a beginning learner of DNS.

Some days ago I built a authoritative name server. Writing zone files, I had wondered why the right side of a NS record is specified not in an IP address but in a domain name.

The IP address of the delegated authoritative for next-level domains is eventually provided in the additional section. If so, it's straightforward to give the IP address in a NS record directly.

Please tell me reasons.

  • This question is off-topic here. Please consider asking somewhere else like the ServerFault stack exchange site.
    – jwbensley
    Jun 16 '15 at 10:01

MX, CNAME, PTR, and NS records point to hostnames. A records point to IP addresses.

Putting an IP address in an NS record is a pretty common DNS misconfiguration. One reason is that you might have NS records pointing to servers outside of your domain for someone doing secondary DNS for you. That remote domain might change the IP address of the server (but leave the hostname alone).

  • I didn't take account of changing the name server's IP address. Jun 16 '15 at 1:55

Not the answer you're looking for? Browse other questions tagged or ask your own question.