How to Flush DNS in your computer

What is DNS flush:

Your computer store DNS records of a domain in a cache memory. So, when you try to hit on that domain, you computer use those DNS records from the cache to make the process faster. Removing the DNS records from your computer’s cache memory is called DNS Flush.

Why you need to flush DNS:

If a domain owner updates DNS or Nameserver of his domain, your computer doesn’t know the update instantly. For this why your computer load contents from it’s old servers as the old DNS records are stored in it’s cache memory. To let your computer know that the DNS has been changed you have to flush DNS.

How to flush DNS:

There are different ways to flush DNS from your computer cache memory for different Operating System. Here I will describe how to do this for all OSs.

Windows 8 / Windows 8.1 /Windows 10

Flushing the DNS cache on Windows 8 and Windows 8.1 is a very easy process. Due to system security permissions, you must ensure that you run the command prompt as an administrator user.

1. Ensure that you’re on the Windows 8 Start Screen.
2. Simply type cmd and the Windows search bar will appear on the right hand side with search results.
3. Right click on Command Prompt and click Run as administrator
4. Type in the command ipconfig /flushdns

Windows Vista / Windows 7

Flushing DNS on newer versions of Windows is almost as easy as the earlier versions but due to Microsoft’s security additions you must run the command prompt with administrator privileges.

1. Click the start button and navigate to the command prompt (Start > All Programs > Accessories > Command Prompt)
2. Make sure that you right click on the command prompt application and choose “Run as Administrator”
3. Type in the command ipconfig /flushdns

Windows 98/NT/2000/XP

Flushing the DNS on Windows is an easy process, outlined below is the steps that should be run if you wish to clear your DNS cache.

1. Open up a command prompt (Start > Run > cmd.exe > OK).
2. Type in the command ipconfig /flushdns

Apple OS X

Flushing the DNS in Mac OS X is an easy process, but the steps taken will depend on which version of OS X you are running.

macOS Sierra

If you are running Mac OS X 10.11, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo killall -HUP mDNSResponder

Mac OS X El Capitan

If you are running Mac OS X 10.11, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo killall -HUP mDNSResponder

Mac OS X Yosemite

If you are running Mac OS X 10.10, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo discoveryutil udnsflushcaches

Mac OS X Mavericks

If you are running Mac OS X 10.9, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo killall -HUP mDNSResponder

Mac OS X Mountain Lion

If you are running Mac OS X 10.8, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo killall -HUP mDNSResponder

Mac OS X Lion

If you are running Mac OS X 10.7, you need to follow the below steps:

1. Open up the command terminal.
2. Run the command sudo killall -HUP mDNSResponder

Mac OS X Snow Leopard

If you are running Mac OS X 10.6, you need to follow the below steps:

1. Open up a command terminal.
2. Run the command sudo dscacheutil -flushcache

Mac OS X Leopard and below

If you are running Mac OS X 10.5.1 or below, you need to follow the below steps:

1. Open a command terminal.
2. Run the command sudo lookupd -flushcache

Other Operating Systems

Linux

If you are running the nscd Name Service Cache Daemon and wish to flush your DNS cache, then you will need to do the following.

1. Open up a command terminal (either as root or run step 2 with sudo).
2. Run the command /etc/init.d/nscd restart