NS レコード
Lists the authoritative name servers for a zone.
NS レコードとは?
NS records tell the DNS system which servers are responsible for a given domain. They appear at the apex of a zone and are also delegated from the parent zone (the TLD operator). Recursive resolvers use NS to find which IPs to ask for further records.
ゾーンファイルの例
example.com. 86400 IN NS ns1.example.com. example.com. 86400 IN NS ns2.example.com.
代表的な用途
- ▸Change DNS providers — update the NS records at the registrar.
- ▸Delegate a subdomain to a different DNS provider.
- ▸Split-horizon / private DNS by changing internal NS targets.
- ▸Diagnose propagation: query NS records via different resolvers (1.1.1.1, 8.8.8.8, 9.9.9.9) to see who has the new set.
よくある落とし穴
The NS set at the parent zone must match the apex NS set inside the child zone. Mismatches ("lame delegation") cause intermittent failures hard to debug.