What is a DNS?

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DNS definition

DNS or Domain Name System is a hierarchical and decentralized naming system for computers, services, or other resources connected to the Internet or a private network. Each device, connected to the internet have unique IP address, like (IPv4) or 2001:db8:3333:4444:5555:6666:7777:8888 (IPv6), which help to identify device on a network. For humans is hard to memorize all these sequences of numbers and in this case helps DNS, which translates human readable webpage names, e.g., google.com, to computer friendly IP addresses.

How it works


Like showed in given example, there are 4 DNS servers involved in a loading of a webpage. Once end user gives webpage address to a browser DNS recursor receive query and start giving request to others DNS servers to bring back webpage. A root server is responsible for looking a specific name server and last portion of a host name (in this example “com”). A name server is responsible to provide a DNS address for a DNS recursor, once request from it was made. Once website server gets command from DNS recursor it translate human readable host name to a machine understandable IP address and it bring back to machine.

How to set DNS on computer


If you want to change DNS to custom, please, follow these steps:

  • Go to Control Panel;
  • Click on Network and Internet;
  • Go to "Network and Sharing Center" and press on Change adapter settings;
  • In a new window select your current network, press on it right mouse button (or double click it) and select press on Properties;
  • Click on Internet protocol Version 4 (TCP/IPv4) and select Properties;
  • If Obtain DNS server adress automativally is enabled, click on the Use the followings DNS server addressess:

DNS settings.jpg

  • Enter the DNS you want to use
  • Click OK and close.

Linux (Ubuntu)

If you want to change DNS to custom, please, follow these steps:

  • Press on the top right corner on network symbol;
  • Click on Settings;
  • Press a cogwheel in your network line;
  • Navigate to IPv4;
  • Click on "Automatic" to disable it and in DNS line add your adress;

DNS on Ubuntu.jpg

  • Click Apply and close window.


If you want to change DNS to custom, please, follow these steps:

  • Press on System Preferences;
  • Navigate to Internet & Wireless and press Network;
  • Depending on how to connect to internet choose WiFi or Ethernet;
  • Click Advanced and navigate to DNS;

Mac DNS.png

  • Press "+", add DNS adress and save.

Most common DNS

If you for some reasons do not want to use ISP provided DNS address, there could be used third party DNS addresses. Most popular are these:

  • Google public DNS: (secondary:;
  • Cloudflare DNS: (secondary:;
  • Quad9 DNS: (secondary:;
  • OpenDNS: (secondary:;
  • Alternate DNS: (secondary:;
  • AdGuard: (secondary:

NOTE:DNS speed in different country may be vary. If you feel, that internet speed with with new DNS is slower than normally, please try out different DNS address.

Useful links

Google DNS home page

Cloudflare DNS home page

Quad9 DNS home page

OpenDNS home page

Alternate DNS home page

AdGuard DNS home page