What is DNS? DNS means Domain Name System and is a decentralized naming system for computers, services, or other resources connected to the Internet or a private network.
DNS translates domain names to the numerical IP addresses needed for locating and identifying computer devices. DNS exists since 1985 and is one of the essential components of the world wide web.
When a user types a domain in the browser, that domain name is translated into an IP address by the DNS resolver. The DNS servers (resolvers) are in contact with the multiple authoritative nameservers, like wordpress.com, Digital Ocean, Vultr, etc.
If the DNS resolver goes offline, users still have access to the Internet, but all the domains will not work. The browser will only work through IP addresses.
Top DNS Servers
1 – Cloudflare
Query speed: 16 ms
Faster in Europe, America and Oceania
Slower in Africa and Asia
IP addresses: 1.1.1.1 and/or 1.0.0.1
Privacy: Using TLS
On PPC Land: Cloudflare created the fastest public DNS beating Google and OpenDNS
2 – OpenDNS
Query speed: 23 ms
Faster in North America, Europe, Oceania and Africa
Slower in Asia and South America
IP addresses: 208.67.222.222 and/or 208.67.220.220
Privacy: Not using TLS
3 – Google DNS
Query speed: 33 ms
Faster in Europe and North America
Slower in Asia, South America, Oceania, and Africa
IP addresses: 8.8.8.8 and/or 8.8.4.4
Privacy: Using TLS
On PPC Land: Google DNS follows Cloudflare and is now using the TLS protocol
4 – SafeDNS
Query speed: 41 ms
Faster in Africa, North America, Europe and Oceania
Slower in Asia and South America
IP addresses: 195.46.39.39 and/or 195.46.39.40
Privacy: Using TLS
5 – Quad9
Query speed: 45 ms
Faster in Europe, Oceania, and North America
Slower in Asia, South America, and Africa
IP address: 9.9.9.9
Privacy: Using TLS
DNS translates domains into IP Addresses
The DNS translates IP addresses. For example the domain ppc.land is hosted in Automattic servers, located in San Francisco. By doing a DNS lookup we can see that the IP Address behind the domain ppc.land is 192.0.78.147. This number identifies the server from Automattic that is hosting our website. Each website is behind an IP Address, and each IP Address has one or more domains.
How to do a DNS Flush on your OS?
Operative systems automatically cache IP addresses and other DNS results. DNS is the process to clear the cache and fix bad results that were cached. Here how to flush the DNS on:
Microsoft Windows 10
- Right click on the start menu and choose Command Prompt (Admin) from the menu.
- Type in the command ipconfig /flushdns
Apple macOS El Capitan, Sierra, High Sierra, Mojave
- Click Applications.
- Click Utilities.
- Click Terminal.
- Run the following command: sudo killall -HUP mDNSResponder
Linux
- Open up a command terminal (either as root or run step 2 with sudo).
- Run the command /etc/init.d/nscd restart
DNS Cache
DNS Cache, also called DNS resolver cache, is a temporary database on the operating system containing recent visits to internet domains. The DNS cache improves the connection velocity to the websites as it memorizes the IP numbers for the domain addresses. When a DNS flush is done, the DNS cache equals deleted.
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