Overview
This article provides instructions on how to clear the DNS Cache on a computers and web browsers. This procedure is necessary in order for previously cached resolutions to be cleared out and subsequent lookup to be performed based on newly configured DNS settings.
Solution
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
- Click the Start Menu
- Go to All Programs
- Choose Accessories and right-click Command Prompt
- Choose Run as Administrator
Run the following command in the command line and hit enter
ipconfig /flushdns
Windows 8
- Press the Windows Key or hover your mouse over the bottom left corner and click the Windows Icon
- Begin typing Command Prompt
- 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
- 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
- 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
- Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal
sudo killall -HUP mDNSResponder
OS X 10.9, 10.10 and 10.11, macOS 10.12, 10.13, 10.14, 10.15, 11
- Click the Terminal icon in the dock or in Finder under Application/Utilities/Terminal
sudo dscacheutil -flushcache
sudo killall -HUP mDNSResponder
Linux (most distributions)
- Open a terminal window (gnome-terminal, konsole, xterm, etc)
sudo /etc/init.d/nscd restartor
sudo /etc/init.d/nscd restart
Ubuntu Linux
- 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. |