IT Learning | Server | NS Record

Everything might be not exactly correct in this article but it’s very useful for beginners to understand IT terms. If you want to learn IT but you don’t have any experience to work in the IT industry, I wish it helps you to understand IT and you like to study IT more.

Let’s start our 3 minutes lesson!

What is NS record?

NS record is written in a zone file.
NS record shows you which DNS server is authoritative for the domain.
NS is an abbreviation for Name Server.

1. Authoritative name server uses NS record

NS record is written in a job handbook for an authoritative name server, and it indicates which DNS server is authoritative for domains. You better know what is Authoritative name server is, so please read the following article.

IT Learning | Server | Authoritative name server | Japan Teams

2. There are two DNS roles

There are two DNS servers. One is an Authoritative name server. Another is called Caching DNS Server. Laptops usually ask Mr Caching DNS server the first question. If Mr Caching DNS server can’t answer the question, he will ask Ms Authoritative name server.

Mr Caching asks Ms Authoritative when he doesn’t have a target in his cheat sheet.

When Ms Authoritative receives the question from Mr Caching, she checks her job handbook called “Zone file”. There is much information in a zone file, and one of the information is “NS record”.

**Ms Authoritative checks her zone file when she answers the question from Ms. caching DNS.**

3. How to write NS record?

How can you write an NS record in a zone file? Here is the format of the NS record in a zone file.

“Domain Name” IN NS “Host name of DNS server”

“Domain name” is the target domain, and NS after IN means that it is an NS record. And “Hostname of DNS server” is the name of the server which manages the target domain. So it is sometimes written the name of the DNS server which has the zone file by itself if that domain is managed by that DNS server.

Then the sample is as follows,

big.meat.com. IN NS ns1.big.meat.com.

4. Notes when you write NS record

There are few more points on NS records to understand DNS.

“Host name of DNS server” should be Fully Qualified Domain Name(FQDN).
You have to write NS records for all DNS servers if there are multiple authoritative DNS servers such as secondary DNS servers.
NS records are used for the hierarchy system of DNS.