Domain Name System Explained: Tips on Managing Your DNS Servers Properly

Domain name system, or DNS, is the phonebook of the Internet. It’s so essential that many companies want to provide you with their DNS servers for free.

Indeed, for years, Google has been offering the popular 8.8.8.8 and 8.8.4.4 DNS addresses. In April 2018, Cloudflare joined the game with a new public server that promises faster speed, better security, and is even easier to remember at 1.1.1.1. And since then, there have been even more free DNS providers.

Among other things, you’d know why so many businesses are so enthused in giving you this type of service. (Hint: They get a lot back in return.)

Dong’s note: I first published this post on April 1, 2018 — when Cloudflare announced its public DNS — and updated it on February 9, 2021, with additional relevant information.

Domain Name System Explained: What it is and how a DNS server works

A DNS server is like a public directory of the Internet. It points you to where you want to go.

(A DNS server is not to be confused with Dynamic DNS, which works somewhat the opposite way.)

Here’s a typical example of the role DNS plays:

Whenever you access a website via its domain name, such as dongknowstech.com, the browser (Chrome, Firefox, Edge, etc.) first queries your DNS server.

For most homes, the Wi-Fi router holds the information of the DNS server in use. By default, that’s the server of the Internet provider.

This server then looks up the website’s domain name (a.k.a. web address or URL) and returns its IP address, which is a string of seemingly random numbers, to the browser — each website resides at an IP address. The browser then follows that IP address to load the website.

This process is necessary because computers only understand numbers while humans are pretty bad at remembering them. This page appears on your screen right now because such a process has worked.

In many ways, a DNS server is similar to the once-commonplace telephone directory service, where you only need to remember a person’s name and not their phone number.

The faster a DNS server is, the less time you need to wait to reach a website, resulting in a “faster” Internet experience — there’s less wait time before a webpage starts to materialize on the screen.

DNS is a matter of privacy and control, too

Since your first need to reach the DNS server before anywhere else on the Inter-web, as you can imagine, the server’s owner, among other things, has the first dibs on your online activities.

Consequently, your DNS server has a log of what websites you visit. More importantly, it has the ultimate control of where you can go on the Internet or block you from accessing specific sites, and so on.

(As such, using DNS is one of the popular ways for networking vendors to provide “Parental Controls” features.)

In short, a DNS server can impact the speed, privacy, and security of your online life.

What is my DNS server?

It’s more a question of who.

By default, if you don’t do anything, your DNS server is that of your Internet provider, which gets the job done but is not necessarily the best. Changing DNS settings allows you more control over your Internet access and can even free you from censorship.

Indeed, while traveling to certain countries, you can access services not available in the local area by using different DNS servers.

The takeaway here is that the DNS server is very important. Make sure you use servers from trustworthy parties. The good news is you can pick your own.

How to change DNS settings to better your Internet

You can change the DNS server settings at a device level (such as a computer) or the router level.

The former works well for mobile users since the DNS settings remain the same no matter where the user is — it’s a good option for a laptop. The latter is useful for the entire network hosted by the router — all devices, by default, will automatically share the DNS settings of the router.

Below are the steps to change DNS server settings.

Steps to change DNS settings in a Windows computer

1. Click on the Start button (lower-left corner), type in ncpa.cpl in the search field, and then press Enter. The Network Connections window will appear.
2. Pick the network connection you’re using — if you’re on a laptop, it’s likely the Wi-Fi connection — and right-click on it, then choose Properties.
3. In the Properties window, double click on Internet Protocol Version 4 (TCP/IPv4)
4. In the next window, check the Use the following DNS server addresses box and enter the addresses for the Preferred DNS server (you can use 1.1.1.1 here) and Alternate DNS Server (you can use 8.8.8.8 here).
5. Repeat step 3, but this time double click Internet Protocol Version 6 (TCP/IPv6) if you have that information (if not, you can skip this step). Then click on OK to close the windows and apply the changes.

Steps to change DNS settings on a Mac

1. Click on the Apple icon (top left corner), then on System Preferences, and then on the Network icon.
2. Select the current network connection (it’s likely the Wi-Fi connection if you’re using a notebook), then click on Advanced…
3. Click on the DNS tab.
   
4. Use the plus (+) button under DNS Servers to enter the addresses of your liking. For example, you can use 1.1.1.1 for the first server and 8.8.8.8 for the second one.

Steps to change DNS on a router

Use the step below to change the DNS servers of the routers’ Internet connection, which are different from those used for the local network.

(You should change the latter — generally found in the LAN section of the interface — when you want the router to dictate which DNS server all connected devices to use. That’s applicable only when you have a special network, such as one with a domain controller or a separate DNS server.)

1. Log in to the router’s web interface.
2. Navigate to the interface’s WAN (or Internet) section; every router has this section.
3. Choose to enter DNS server addresses manually (basically, you want to disable the default value that lets the router automatically pick the service provider’s DNS servers).
4. Enter the DNS addresses of your liking, such as 1.1.1.1 for the primary server and 8.8.8.8 for the secondary (backup) server.
5. Apply the changes.

Domain Name System: The takeaway

Considering your DNS’s significant role, again, make sure you pick one you can trust when changing the values manually. When in doubt, leave the setting as Auto, and the system will use the default, which generally is that of your Internet provider.

Changing the DNS setting is also a popular way to “hack” a system. In this case, the bad guys capture your DNS requests to send you to phony destinations or services. Make sure you’re aware of your DNS settings, especially at the router’s level.