DNS query – What is it?

If you’ve ever wondered how websites, emails, and other online resources can be located online, the answer is DNS queries. A DNS query is a process used to locate and provide information about a particular domain name or IP address and is a vital part of the resolution process. Keep reading to learn more about a DNS query and how it works!

Purpose of DNS query

A DNS query, or a Domain Name System query, is a process used to locate and provide information about a particular domain name or IP address. It is responsible for answering questions such as “which server is hosting a particular website?” The query is sent out to a DNS server, which contains the necessary records and IP addresses associated with the particular domain or address to be located. DNS queries are an essential part of the domain name resolution process, as they allow clients to access websites, emails, and other online resources elsewhere.

The importance of DNS queries

How does it perform?

When a user attempts to access a website or other online resource, the Domain Name System query process begins by sending a query to the Domain Name System server to locate the proper IP address. DNS servers are responsible for keeping records of which server is hosting each domain name, so the Domain Name System query is needed to ask the server which IP address the domain name is associated with. Once the DNS server replies with the correct address, the client’s system can connect to the appropriate server, allowing the user to access the website or resource requested.

Types of DNS query

The two types of DNS queries are recursive and iterative. A recursive query requests a response until the desired information is obtained. A DNS recursive query will send out the query and then wait for the server to reply with the requested records. An iterative query begins with the highest-level DNS server. When the highest level server cannot provide the requested record, the query is sent down to the next level of the DNS server to try and locate the information. This process of sending queries down the DNS server hierarchy continues until the requested information has been returned.

A third type of Domain Name System query is known as a zone transfer. This type of query is used when a DNS server needs to update itself with new records and is sent from one Domain Name System server to another to facilitate the transfer. The results of the zone transfer query contain all the information requested and any additional records added to the new server. This ensures that the DNS servers have the most up-to-date information and can respond quickly to client queries.

Finally, a fourth type of query is referred to as a reverse Domain Name System query. This type of query is used to try and look up an IP address associated with a particular domain name. This type of query can be helpful when troubleshooting network problems or trying to locate the physical location of users or servers. Reverse DNS queries can also help verify if a particular website is authentic or not since it can provide the IP address it is associated with.

Conclusion

In conclusion, DNS queries are essential for website resolution and are a powerful tool for finding domain names and IP addresses. Understanding the different types of DNS queries and how they work can help you increase the speed and efficiency of your web searches, so you can get to the resources you’re looking for quickly and easily.

Recursive DNS server – Main characteristics

Many people still ignore the importance of the Domain Name System (DNS) in our daily lives. The Internet gets the complete spotlight, but it totally relies on the DNS and its different components, the recursive DNS server, for instance. Let’s know the main characteristics of this important DNS component.

Recursive DNS server – Main characteristics

A recursive DNS server has an important job. It is in charge of searching the necessary data to respond to clients’ DNS requests.

When a user (potential client) requests a domain name through her or his browser, a recursive DNS server will look for the associated IP address of that domain. Without this information, the domain can not be loaded for the user. The recursive DNS server won’t stop its search due to one of its main characteristics, “recursion”. In the computing science field, recursion means a process or solution that repeats itself the necessary number of times to reach a specific goal. So the recursive server will look for the IP address until it finds it.

Once the DNS recursive server obtains the IP address, it will deliver it to the user’s browser. Then, and only then, the domain can be loaded by the user.

Another characteristic of a DNS Recursive server is that it has two ways to execute its job.

1. It can look for the DNS information needed to respond to the DNS requests within its cache. There is a chance for information to be kept available there. It will depend on the time-to-live (TTL) value previously set on the DNS record. If this TTL has not expired, the recursive will get the information and respond to the user very fast.

This is possible because the recursive DNS server’s cache can keep information for a specific period of time, not permanently. How long? The defined time on the TTL of DNS records (decided by administrators).

2. If the DNS record has never been inside the cache or the TTL has already expired, the DNS recursive server won’t find the necessary IP address in its cache. Then, the recursive will use a “B” plan. That means it will ask other servers for information. Its search must lead it to the exact, authoritative server that has the DNS information. It takes longer than checking in the cache, but it is an effective way to obtain DNS information.

When we say “longer”, we talk in milliseconds. It is a fast process.

To summarize, DNS recursive servers are essential for the DNS resolution process. Without them, DNS requests can not be answered. Therefore users can not load domains.

There are plenty of Recursive servers working 24/7, worldwide. Every user requesting a domain is a call to a recursive server to start a search.

DNS recursive servers search that is their duty, search for DNS information. They can keep DNS information but only temporarily.

Conclusion

Recursive DNS servers are essential for users to reach your online business! Walking through their main characteristics, you can better understand their value.