A DNS server is a computer server that stores DNS records. Its primary function is to translate domain names (like “example.com”) into IP addresses (like “192.0.2.1”), which computers use to communicate with each other over the internet. Here’s a more detailed breakdown:
Core Functions of DNS Server:
- Translation: The fundamental job of a DNS server is to respond to requests for domain name resolution. When a user enters a website address into their browser, the browser queries a DNS server to find the corresponding IP address.
- Record Storage: DNS servers hold databases of DNS records, which contain information about domain names and their associated IP addresses, as well as other data.
Types of DNS Servers:
- Recursive DNS Servers (Resolvers): These servers handle queries from end-user devices. They may cache previously resolved domain names and, if necessary, query other DNS servers to find the correct IP address.
- Authoritative DNS Servers: These servers hold the definitive DNS records for specific domains. They are responsible for providing the final answer to DNS queries.
- Root Servers: These servers are at the top of the DNS hierarchy. They provide information about top-level domain (TLD) servers.
- TLD Servers: These servers hold information about domains within specific TLDs (like .com, .org, or .net).
How a DNS server works?
- When a user types a domain name, a query is sent to a recursive DNS resolver.
- The resolver may have the IP address cached. If not, it queries root servers, then TLD servers, and finally authoritative servers to find the IP address.
- The IP address is then returned to the user’s device, allowing the browser to connect to the website.
In essence, DNS servers are essential for making the internet user-friendly, allowing us to use memorable domain names instead of complex numerical IP addresses.
