Flush DNS

Flushing the DNS records on your computer is something that can prove quite useful when trying to speed up DNS Resolution for a newly added or modified domain in your account. While it's not an end-all solution to speeding up propagation, it will at least remove the local cache from your system and allow you to grab the most recent cache that your ISP has.

Windows XP

 * 1) Click the 'Start' button and then click on 'Run'.
 * 2) Type in  and click 'OK'.
 * 3) In the window that comes up, enter in:
 * 4) Press the 'Enter' key and repeat the process two more times.
 * 5) Type  and press the 'Enter' key to close the window.

Windows Vista

 * 1) Click the 'Start' button and then type 'cmd'. (Into the search box if not already selected)
 * 2) When you see "cmd" highlighted, hold down 'Ctrl' + 'Shift' and hit 'Enter'. Or, you can right click on it and select "Run as administrator".
 * 3) Select 'Continue' at the "User Account Control" screen.
 * 4) In the window that comes up, enter in:  and hit enter.
 * 5) Press the 'Enter' key and repeat the process two more times.
 * 6) Type  and press the 'Enter' key to close the window.

If you wish to instead verify what domains and IPs your computer currently has cached, you may use the command  in the steps above.

Windows 7

 * 1) Click the 'Start' button and then type 'run' in the search bar (where it says 'search for program and files').
 * 2) Where it says Open: type in 'cmd'.
 * 3) In the window that comes up, enter in:
 * 4) Press the 'Enter' key and repeat the process two more times.
 * 5) Type exit and press the 'Enter' key to close the window.

10.4 (Tiger)

 * 1) Open up a terminal window (Located in /Applications/Utilities).
 * 2) Flush your DNS cache with the following command:
 * 3) Type  and press the 'Enter' key to close the window.

10.5 (Leopard), 10.6 (Snow Leopard), 10.7 (Lion), and 10.8 (Mountain Lion)

 * 1) Open up a terminal window (Located in /Applications/Utilities).
 * 2) Flush your DNS cache with the following command:
 * 3) Type  and press the 'Enter' key to close the window.

Note: some Lion users report that dscacheutil does not work on 10.7 or 10.8. The alternative you could try running in the Terminal is:

sudo killall -HUP mDNSResponder

(via HenryAZ on macrumors.com)

Steps to flush your DNS cache in Linux

 * 1) Open up a terminal window (Location varies by distribution).
 * 2) Flushing your DNS cache is done by restarting the 'nscd' daemon and may be done with the following command:
 * 3) Or you may manually stop and start the daemon with the following commands:
 * 4) Type  and press the 'Enter' key to close the window.
 * 5) On Ubuntu 11.04, I had to use these commands:
 * 1) Type  and press the 'Enter' key to close the window.
 * 2) On Ubuntu 11.04, I had to use these commands: