nslookup queries

You all must have used the nslookup command to query the dns servers and get specific information.

Ever noticed whenever you query a dns using nslookup it gives you sections like “Authoritative Answer” and “Non-Authoritative Answer”. Ever wondered what it is all about.

Any answer that is coming from the DNS Server which has the complete zone file information available (like master or slave dns servers) for the domain is said to be – Authoritative Answer.

If the answer is supplied by the “Caching Only DNS Server“, which will not have the complete zone file, instead it relies on the previous query cache to give the answer, that cache information is the result that the server got from Authoritative response from either master / slave dns servers. That response is classified as – Non-Authoritative Answer.

Here is a screen shot from my machine.
nslookup queries

nslookup queries

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