What is the difference between Authoritative and Non-Authoritative DNS Servers?
To answer this question, we need to describe the following types of DNS services:
Authoritative DNS servers are responsible for the proper mapping of records and to respond to the recursive servers with important information for each website, such as; corresponding IP addresses and other necessary DNS records.
Non-authoritative name servers do not contain the original zone files. They may have a cache with previously requested DNS records from all the DNS lookups done previously. If a DNS server responded to a DNS query that doesn’t have the zone file, it is a Non-authoritative answer.
- Recursive and Iterative DNS queries
A recursive DNS lookup is where one DNS server communicates with several other DNS servers to resolve an IP address and return it. With iterative queries, a client communicates directly with each DNS server involved in the lookup.