NSrecords

NS records, or name server records, are a type of DNS resource record that designate the authoritative name servers for a domain or zone. They tell resolvers which servers hold the DNS data for the domain and where to send queries that require authoritative answers.

A domain may publish multiple NS records to provide redundancy and distribute load. Each NS record identifies the hostname of an authoritative server, such as ns1.example.net or ns2.example.net. The NS values are hostnames, and the corresponding A or AAAA records of those hosts are used to reach the servers. If an NS hostname is inside the same zone, the parent zone may include glue records (A or AAAA) to prevent a circular dependency during resolution.

During DNS resolution, resolvers consult the NS records at the parent zone to learn which servers are authoritative for the child zone. The resolver then queries one or more of the listed servers to obtain answers. NS records are typically published at the zone apex to designate the authoritative servers for that zone; subdomains can also publish their own NS records to delegate to another set of servers.

Management and considerations: It is common practice to specify at least two authoritative servers in different networks or providers for resilience. Changes to NS records require DNS propagation, and mismatches between parent and child zone configurations can lead to resolution failures. While DNSSEC signs zone data to protect integrity, it does not by itself validate delegation; proper signing and key management are required.