The following tables provide instructions for clearing the DNS cache on computers and servers. The commands need to be run at the command prompt with administrator privileges.

 

 

Windows 7 and Earlier

 

  1. Click the Start Menu
  2. Go to All Programs
  3. Choose Accessories and right-click Command Prompt
  4. Choose Run as Administrator

     Run the following command in the command line and hit enter

ipconfig /flushdns

  



Windows 8 and Windows 10

 

  1. Press the Windows Key or hover your mouse over the bottom left corner and click the Windows Icon
  2. Begin typing Command Prompt
  3. Right-click the application and select Run as Administrator

     Run the following command in the command line and hit enter

ipconfig /flushdns

   



OS X 10.4 TIGER

 

  1. Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal

     Run the following command in the command line and hit enter

lookupd -flushcache

    



OS X 10.5 and 10.6 LEOPARD

 

  1. Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal

     Run the following command in the command line and hit enter

dscacheutil -flushcache

     



OS X 10.7 and 10.8 Lion

 

  1. Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal

    Run the following command in the command line and hit enter

sudo killall -HUP mDNSResponder

     



OS X 10.9 and 10.10.4 Yosemite, 10.11 El Capitan and 10.12 Sierra

 

  1. Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal

    Run the following commands in the command line and hit enter

sudo dscacheutil -flushcache
sudo killall -HUP mDNSResponder

    



Linux (most distributions)

 

  1. Open a terminal window (gnome-terminal, konsole, xterm, etc)

    Run the following command in the command line and hit enter

sudo /etc/init.d/nscd restart

   or

sudo /etc/init.d/nscd restart

    



Ubuntu Linux

 

  1. Open a terminal window

     Run the following command in the command line and hit enter

 sudo service network-manager restart

 



Clearing the DNS Cache on Browsers

 

 

If you have recently set up your filtering, or just changed a setting, a cache clear may be necessary before you see your filtering take effect.

The following table provides instructions for clearing the DNS cache within common Internet browsers.

 

Browser

 

Steps to clear the DNS Cache

 

Internet Explorer 8 and above (Windows)
 
Go to the History menu, select Delete Browsing History, check all boxes (except passwords, if desired) and click Delete.
 
Mozilla Firefox (Windows)
 
Click on Firefox at the top left of your browser, go to the History menu, select Clear Recent History and check all boxes. Under Time range to clear select Everything (except passwords, if desired) and click Clear Now.
 
Apple Safari (Mac)
 
Expand the Cog Icon in the upper right corner and select Reset Safari. Check all boxes and click Reset.
 
Apple Safari (Windows)
 
Go to the Safari menu, select Reset Safari, check all boxes and click Reset.
 
Google Chrome (Windows)
 
Expand the Wrench Icon in the upper right corner and select History and check all boxes. Under Clear data for this time period, select Everything(except passwords, if desired) and click Clear Browsing Data.
 
Google Chrome (Mac)
Under Go to the Chrome menu, select Clear Browsing Data and check all boxes (except passwords, if desired). Under Clear data for this time period,select Everything and click Clear Browsing Data.