Have you heard of the term DNS? Did you stumble on error messages that told you that the DNS server can’t be reached? Do you know what a DNS is and what is its purpose? If you don’t know, then you should read this guide. We explain what DNS is, its role on the Web and how you can learn your existing DNS settings in Windows:
What is DNS (Domain Name System)?
DNS stands for “domain name system” and it is a standard used for managing the IP addresses of websites all over the world. In computer language, each and every website on the Web has an IP address where it can be found. For instance, our Digital Citizen website can be found at the IP address 184.108.40.206. Computers and other devices have no issues in remembering and using IP addresses for an unlimited number of websites. However, people like you and me have a hard time doing that. In the end, it is so much easier to remember www.digitalcitizen.life than it is to remember 220.127.116.11.
That is why the DNS technology exists: to translate the IP addresses of websites on the Internet into something readable and easier to understand and remember for us humans.
In a way, you could look at the DNS tech like at a huge phonebook that associates a name to every phone number in the world. The only difference is that instead of phone numbers, you have IP addresses. It’s normal for us to remember our friends’ names, but not their phone numbers. When you want to call one of your friends, you just open the phonebook on your smartphone and call him or her by their name. You don’t have to remember your friends’ phone numbers. Similarly, you don’t have to remember the IP address of a website in order to be able to visit it. You just need to remember its name, and the DNS technology automatically associates it with the correct IP address.
How do DNS servers work?
Now you know what DNS stands for and what it does. But how does it do what it does? The answer is: the DNS does its job through DNS servers. They are special servers that store large databases with IP addresses of various websites on the Internet, as well as the IP addresses of other DNS servers that do the same thing.
When you want to visit a website, your computer or device asks its DNS server if it knows the IP address of that website. If it does and your computer receives an answer, you are immediately relayed to that website’s IP address. This process is called a DNS lookup. It’s like the search function on your smartphone’s phonebook.
It can happen though, that the DNS server configured to work with your computer, doesn’t know the IP address of a website that you’re trying to visit. That can happen, because maintaining a database with all the websites in the world is a titanic task. However, DNS servers are not lost islands in a sea of websites: they are also connected among themselves and they also maintain a hierarchy. If it happens that a DNS server doesn’t know the IP address of a certain website, it will relay the question to another DNS server that is higher in the hierarchy. When a result is found, the response is forwarded back to you.
It’s worth noting that this entire “ask and respond” process happens in milliseconds so it’s very fast and you won’t know which actual DNS server has relayed the IP address of the website that you are trying to visit. However, present day computers, devices and programs don’t like any delay, as small as it might be, so most computers and devices also keep a cache of their DNS requests so that they can open a website you’ve already visited faster, the next time you visit it.
If you’re wondering who maintains DNS servers, you should know that such servers are maintained by a whole range of different entities, starting from your Internet service provider to governmental organisations and universities all over the world. A bit earlier in this article, we briefly mentioned that the DNS servers are not only communicating among themselves, but they also have a hierarchy put in place. This statement probably made you curious to find out which DNS server is the “king of the hill”. :) Here’s the answer: there are 13 kings, meaning that all the DNS servers in the world relay to these 13 main “top of the food chain” DNS servers. They also bear the name of “root servers” and, if you want to know who maintains them and where they’re geographically located, you’ll find the list here: Wikipedia - Root name server. As you will see, most of them are located in the United States of America.
Where can I see the DNS servers used by my Windows computer or device?
If you are a Windows user, there are many ways in which you can find the addresses of the DNS servers that your computer or device is using.
One way to find their addresses is via the Network and Sharing Center. Open it and then click or tap on the network adapter you use for connecting to the Internet. In my case, for instance, that would be the Ethernet adapter used by my RDS Internet connection.
This opens a window that shows the Status of the network adapter. There you will see a button called Details. Click or tap on it.
In the Network Connection Details window, you will find the DNS servers your Windows computer or device uses. They are listed in the fields named IPv4 DNS Server and IPv6 DNS Server.
A slightly faster way of finding which DNS servers you use on your Windows computer or device is to use the Command Prompt or PowerShell. In the command line environment that you prefer, run the following command:
ipconfig /all | findstr /R "DNS\ Servers"
Both Command Prompt and PowerShell will show you the addresses of the DNS servers that your Windows computer or device is set to use.
Now that you know the basics of what the DNS technology is and how it works, you will have an easier time understanding certain issues you stumble upon when browsing the Web. If you have any questions about DNS or you would like to share more information about DNS servers, don’t hesitate to use the comments form below.