What is DNS?
DNS is an acronym for Domain Name System (also referred to as Domain Name Service). When you open a website on your computer, the DNS information of that website is cached in your computer memory. So that when you visit the same website next time, the resource record may be referred from cache.
This may cause problems if the website’s DNS information has changed since you last visited the website. For such instances, you may require to force your computer to flush the DNS cache.
The following commands can be used in different operating system to flush the DNS cache.
Flush DNS on Windows OS
- Click on Start button.
- Select Run..
- Type “cmd” and press OK button.
- You should see the following line: C:\Documents and Settings\User>. Type:
ipconfig /flushdns
You will see a message containing the following:
“Windows IP Configuration Successfully flushed the DNS Resolver Cache.”
Type “exit” to close the prompt.
Flush DNS in Mac OS X
- Click on Finder in the dock.
- Click on Macintosh HD.
- Click on Applications.
- Click on Utilities.
- Double-click on Terminal.
On Mac OSX Leopard or newer versions, you can use the following command to flush the DNS resolver cache:
dscacheutil -flushcache
For Mac OSX 10.5.1 or earlier versions, you can use the following command:
lookupd -flushcache
Flush DNS in Linux OS
In Linux, the nscd daemon manages the DNS cache. To flush the DNS cache, restart the nscd daemon. To restart the nscd daemon, use the following command.
/etc/init.d/nscd restart