What are NS Record's ?

NS (Name Server) Records are used within the Domain Name System (DNS) to determine which name servers are authoritative for a domain. NS records also provide name server delegation.


Within this example we have a domain named The parent zone (.com) will contain the NS records for this zone. 
Now, if we wanted to create a sub domain, lets say '' and host the zone on name server '', we would add an additional NS record to the zone defining this name server delegation.

Glue Records

Glue records are used to prevent circular dependencies. Circular dependencies occur if the name server referred to is under the domain that it is authoritative for.

An example is when you have a domain called Your name servers are and A client tries to resolve The client (via the TLD servers) receives the name servers that are authoritative for this domain (which are ns1/ In order to locate ns1/ns2, the parent domain ( first needs to be resolved. However resolving (once again) results in the authoritative name servers being returned (ns1/ and in turn a circular dependency is created.

Glue records are supplied by the TLD servers within their responses i.e the name servers are supplied, but additionally the IP addresses of these name servers are also supplied. (Because this additional information is supplied by the TLD servers) Glue Records are created via your domain registrar.

Stealth Name Servers

A Stealth Name Server is a name server that is defined within a zone but it not defined on the parent name server(s).

About the Author


R Donato

Rick Donato is the Founder and Chief Editor of He currently works as an SDN/NFV Solutions Architect and has a keen interest in automation and the cloud.

You can find Rick on Twitter @f3lix001