Nameservers and NS records

An NS record names a server that is authoritative for a zone.

The parent zone publishes the delegation. For example.com, the .com zone tells resolvers which nameservers should answer for example.com.

The child zone also publishes an NS set at its apex. In a healthy setup, the parent delegation and the child’s authoritative data agree. A mismatch can make diagnosis confusing because different queries may expose different sets.

An authoritative nameserver is a DNS service. It is not necessarily the machine hosting the website or receiving email.

When a nameserver’s hostname is inside the delegated zone, the parent may need glue address records. Without glue, resolving ns1.example.com could require first asking the very nameserver whose address is still unknown.

Changing nameservers moves authority, so prepare the destination first:

1. Recreate and verify the complete zone at the new DNS host.
2. Copy the exact assigned nameserver names into the registrar’s delegation settings.
3. Keep the old zone available while parent and resolver caches expire.
4. Query the new authoritative servers directly before declaring the move complete.

Do not confuse registrar settings with records in the zone editor. The registrar updates the parent delegation. Adding an NS record only inside the old zone does not normally move the registered domain to a new provider.

Inspect the public result:

dig NS example.com +short
dig +trace example.com NS

Then save one listed server and query it directly:

authoritative_server=$(dig NS flaviocopes.com +short | head -n 1)
dig @"$authoritative_server" flaviocopes.com SOA +norecurse

Your action is to record the nameservers returned by an ordinary query and a trace. If they differ, identify whether you are seeing a cache, the parent delegation, or child-zone data.