DNS (Domain Name System) is like a phone book for the World Wide Web. All websites and domains are mapped to a unique IP address. Humans access information on the internet through domain names, like facebook.com, Google.com. When you type in such domain names in the address bar on your browser, DNS does the mapping behind the scenes translating the domain names to unique IP addresses so browsers can load the internet resource requested.
Each device connected on the internet has a unique IP address that other machines use to identify it. Without DNS servers, human users would need to memorize IP addresses such as 192.168.21.14 to reach destinations on the World Wide Web.
A DNS cache is a temporary database maintained by a computer’s operating system which records in log files all of the recent visits to a website and other internet domains.
In other words, just like caching on your WordPress site, DNS cache is a memory of recent DNS lookups of websites and internet domain visited that your computer can quickly refer to when it’s trying to load a website. The DNS records in this cache need to be up to date at all times for accurate DNS resolutions. The need to clear DNS cache arises if the DNS becomes out of date or things change on the webserver.
- DNS flushing: what is does
- Clear DNS Cache Windows
- Clear DNS Mac
- Clear DNS cache for chrome
DNS FLUSHING: what is does
When troubleshooting internet connectivity issues, one of the options available could be for the system administrator to flush the DNS cache. This flushing erases and resets cache content.
Since clearing the DNS cache erases and resets all the entries, it removes any invalid records enabling your computer to repopulate those addresses the next time you try accessing the websites.
Thus, the new addresses populated are gotten from the DNS server your network is set up to use. So, in a scenario, let’s say a website facebook.com isn’t loading fine or say is redirecting you to an external website, when access to such a site is seamless in another computer, flushing the DNS is an excellent first step to fixing this problem.
Network routers have DNS cache as well. If DNS errors persist after troubleshooting on the PC, the next step might be rebooting the network router. For the same reason, you might flush a DNS cache on your PC, rebooting a router clears the DNS entries stored in its volatile memory.
Clear DNS Cache Windows
To clear DNS cache on Windows, follow the steps below:
Step1: Punch the Windows key to launch the start menu and then search for “CMD.” This should return the command prompt.
Step2: In the command prompt run the command: “ipconfig /flushdns”
Step3: A confirmation about the success of the flush operation would be displayed on the screen
Clear DNS Mac
To clear DNS cache on Mac, follow the steps below:
Step1: Click “Go” located up in the toolbar, then proceed to click Utilities (Shift-Command-U).
Step2: Open the terminal
Step3: Run the following command. note: administrator access is needed for this operation. “sudo killall -HUP mDNSResponder && echo macOS DNS Cache Reset.”
The above command clears the DNS cache; hence, you can now try accessing the domain that was having issues.
Clear DNS cache for chrome
Chrome cache is a browser cache that is different from the local DNS cache on the computer. You can resort to clearing a chrome DNS cache if you are using a chrome browser and after clearing the local DNS cache, the issues with IP or domain resolving persists. Use the steps below to clear a Chrome DNS cache:
Step1: input the codes below in your Chrome address bar and hit the enter key.
Step2: Click on “Clear host cache.” to clear the DNS cache.