Recursive DNS server: How does it work?

Recursive DNS server is a crucial element of the Domain Name System. If you want to learn more about it, you are on the right page. So let’s begin.

DNS – what does it mean?

The Domain Name System (DNS) is what allows domain names to be translated into IP addresses. This is the common language that machines use to communicate with one another.

Vulnerabilities of Recursive DNS servers

Using the Internet before DNS was a more challenging experience. To get to the domains you want to visit, you had to type IP addresses. This necessitated typing large numbers sequences into the browser. It was a time-consuming task. In addition, long digits were difficult to remember, and the odds of making a mistake were high.

It is easier to type example4domain.org weather than 214.136.89.63.

DNS was intended to make this operation as straightforward as possible. Simple domain names are easy to remember. DNS tells machines what domains to look for in their language.

The definition of Recursive DNS server

A Recursive DNS server or DNS resolver is an expert in searching. Yes, it’s the one that looks for the information needed to respond to DNS queries from users.

It’s an essential and efficient part of the DNS system. Recursive is derived from the word recursion. In computing, a solution or a specific process will repeat as many times as necessary to achieve a goal. And that description closely resembles how a Recursive DNS server works.

When a user requests a domain using a browser, a DNS resolver is the first stage to find the domain’s corresponding IP address. It can be quick and straightforward to obtain or require additional steps and effort. On the other hand, the server will not stop looking for it until it finds it. Then it will deliver it to the browser, which will then load and access the asked domain for the visitor (device).

How does Recursive DNS server work?

The recursive DNS server has two modes of operation. They are the following:

The first way is thought to be much simpler and speedier. The Internet address(IP) is stored in its cache memory. These servers can save the information in their cache for a specific period of time. It is up to the administrators to decide how long they should keep it. They can use the time-to-live (TTL) to evaluate whether they need more or less time. Actually, it’s all reliant on the administrators’ plan.

When the recursive DNS server receives the query, it will first look for the IP address in its cache memory. The assignment is complete if that information is still available there and the TTL has not yet expired. It’s advantageous since the answer is quick, and the recursive DNS server doesn’t have to look for information on other servers.

The second way of the search will take a little longer to finish. It occurs when the cache’s TTL has passed its expiration date. As a result, the IP address is no longer accessible. On the other hand, the recursive DNS server goes a long way toward obtaining the needed information. It travels from the root server to the TLD (Top-Level-Domain) server to the authoritative server, which is the one that can answer the question.

Conclusion

In conclusion, we can say that recursive DNS servers are essential for making the resolution process and the Internet, in general, more flexible. As a result, their numbers are significant, and their presence is widespread. Recursive servers are used by every Internet Service Provider (ISP), and they aren’t just for ISPs. DNS service providers, domain registrars, and various network providers are all using it.