Domain name servers (DNS) are the main database of information that is used to search for domain names and IP addresses. DNS essentially acts like a phone book for the Internet. The server handles requests from both clients and other DNS servers. It also caches information for a limited period of time. Eventually, the information is distributed throughout the network.
A user makes a query using a browser or software application. They enter the name or domain of the website they want to visit and the type of record they are looking for. If the name is not found, the query will return an error. Once the result is returned, the web browser displays the webpage.
What is the Purpose of Domain Name Servers?
When a user visits a webpage, it uses DNS to convert the web page’s host name into an IP address. This process is called translating the host name. Historically, these translations were done by a computer using a text file. However, this was a difficult process. To overcome this limitation, the Domain Name System was developed. The DNS is a network-based system that distributes data and information to millions of computers across the world.
Each domain has a top level domain (TLD) and an authoritative DNS server. The TLD and authoritative DNS servers are responsible for storing and publishing information about the name and its subordinate domains. In addition, a secondary server is also maintained for a given DNS zone.
How Does DNS Work?
Authoritative DNS servers contain the original records for every domain and IP address. As such, they are the last point of reference for any information about a domain. The authoritative DNS server can be either the primary server or a secondary server. Depending on the type of domain, the primary or secondary servers may have to communicate with each other.
These servers are usually part of the website hosting service provider’s network. For example, if a client wants to access a webpage hosted by a particular ISP, the DNS recursor will send the request to the authoritative DNS server, which will respond with the IP address of the domain. Alternatively, if the DNS recursor is unable to find the IP address, it will send the query to the root name server.
Root Servers within DNS
Root name servers are located at the very root of the domain name system. As such, they are primarily involved in a very small fraction of all DNS queries. Those that do involve root name servers are called recursive queries. Recursive queries are not required for every domain. There are some exceptions, however.
Whenever the recursor receives a query from a client, it forwards the query to the root name server. After the root name server receives the query, it prepares a DNS search sequence. An recursive search results in the recursor making a series of DNS queries, until it reaches the authoritative DNS server. Finally, it returns the resulting answer to the client.
The entire process can take several seconds. During this time, DNS servers and other DNS servers interact to provide redundancy. They communicate regularly, and this allows them to be resilient in case of failure.
How to Use Domain Name Servers
If you’re still struggling to understand how to use DNS for your domain name, it’s important to learn how. Browse the FAQ section of your domain registrar to see how they can set up DNS. This will be needed for landing pages and selling your domain through a broker.