Domain Name System (DNS) is Often called the internet’s phonebok. Human can easily remember names like google.com but computers comunicate with IP address such as 142.250.183.14. DNS exists to translate domain names into IP addresses, this process known as name resolution.

Without DNS , users need to remember IP addresses for each website, which is quite difficult task.

What is DNS and why name resolution exists

dig (Domain Information Groper) is a DNS diagnostic and troubleshooting tool that is used to query DNS servers and inspect how name resolution works.It is commonly used to Debug DNS issues, understand which name servers are responsible for a domain, inspect DNS records (A, NS, MX, etc.), learn how DNS resolution happens step by step.

eg:- dig chaicode.com

How DNS resolution happens

DNS resolution happens followingly

dig.NS and root Name Servers

command:- dig.NS

This query asks “Who are the name servers for the root zone?“

This . represents the DNS root. Root server do not store domain IPs. They only direct the queries to correct TLD servers.

Root DNS Server:- These are the highest-level DNS servers and know where to find the TLD servers. They are crucial for directing DNS queries to the correct locations.

dig com Ns and TLD Name Servers

command: - dig com NS

This query asks “Which name servers manage the .com domain?“

TLD Servers:- Top Level Domain (TLD) servers manage domain extensions like .com, .org, .net, .edu, .gov and others. They know which authoritative servers are responsible for domains under them.They help route queries to the authoritative DNS servers for specific domains.

dig google.com NS and authoritative name servers

command: - dig google.com NS

This query asks “Which name servers are authoratitative for google.com?“

Authoritative Name Server:- These are the servers that store the actual DNS records for domain names. They are responsible for providing the correct IP addresses that allow users to reach websites.

dig google.com and the full DNS resolution flow

command: - dig google.com

This query returns the final IP address .

Step by Step Resolution flow:-

when we type https://google.com in a browser:-

1.Browser ask the recursive resolver for the IP

2.resolver follows the pattern Root → TLD → Authoritative server

3.Authoritative server returns the actual IP address.

4.Browser connects to the Server with the IP.