example.com. 86400 IN NS a.iana-servers.net.
NS records (name server) say which servers are authoritative for a zone — the ones that hold its real records. They appear in two places: in the parent zone (the TLD registry’s delegation) and in the zone itself. Both sets should match.
How delegation works
A resolver looking up www.example.com asks a root server, which refers it to the .com servers, which refer it to example.com’s NS records. If the name servers are inside the zone itself (ns1.example.com), the parent also publishes their addresses as glue records to avoid a chicken-and-egg problem.
Best practice
Use at least two name servers on different networks. NS targets must be hostnames with A/AAAA records, not CNAMEs. Changing name servers is done at your registrar, not in the zone.
Frequently asked questions
- How do I change my domain's name servers?
- At your domain registrar. They update the delegation in the TLD registry; the change is visible once the old NS records' TTL expires.
- Why do the NS records at the registry and in my zone differ?
- The parent's delegation and the zone's own NS set are maintained separately. Keep them identical to avoid inconsistent resolution.