NS record
The DNS record listing the authoritative nameservers for a zone; set at the registrar, it decides which DNS host's records the world sees.
What it means
NS records appear in two places: in the parent zone (com for example.com), where the registry publishes the delegation you set at your registrar, and at the top of your own zone. Resolvers follow the parent's NS records to find your servers.
Changing nameservers moves the whole domain to another DNS host. Every record must already exist at the new host, or mail breaks: MX, SPF, DKIM and DMARC records left behind simply stop existing. Resolvers also cache the parent zone's delegation, and that TTL is set by the registry rather than by you, so the switch takes longer than an ordinary record change.
NS targets must be host names with address records, not CNAMEs.
Example
example.com. 86400 IN NS ns1.dnshost.example.Related terms
On this site
Sources
What this definition rests on. The wording is ours; the facts are theirs.
- RFC 1034: Domain Names: Concepts and Facilities, section 4.2rfc-editor.org
- RFC 1035: Domain Names: Implementation and Specification, section 3.3.11rfc-editor.org
- RFC 9499: DNS Terminology, section 7rfc-editor.org
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