How to Clear/Flush DNS cache in Windows / Linux / Mac Machines

[Rsync]

DNS
A DNS server resolves domain names into IP addresses. So when you request “eukhost.com” for example, the DNS server finds out the address for the domain, and sends your request the right way.

DNS Cache Problem
If you continually get DNS errors while trying to brows any site, but the same site on another computer on the same network is working fine. Then this problem is because of the DNS cache of the machine and you need to reload your DNS cache on that machine.

Following is the process to Clear/flush DNS cache in Windows / Linux / Mac Machines

To Clear/flush DNS cache in Microsoft Windows.

Start >> Run >> type cmd

In command prompt, type

C:\> ipconfig /flushdns

OR

In command prompt, type

C:\> net stop dnscache
C:\> net start dnscache

Once you run the command your Window DNS cache will Clear/flush.

To Clear/flush the DNS cache in Linux, you need to restart the nscd daemon.
You need login into the shell of your machine and type

root@support [~]# cd /etc/rc.d/init.d
root@support [/etc/rc.d/init.d]# ./nscd restart

Once you run the command your linux DNS cache will Clear/flush.

To Clear/flush the DNS cache in Mac OS.
In your terminal, type
For Tiger Mac

$ lookupd -flushcache

For Leopard Mac

$ dscacheutil -flushcache

Once you run the command your DNS cache (in Mac OS) will Clear/flush.

[Marksfish]

There is a problem with this when runing the command on Vista. I finally found the answer myself today after months of frustration.

If you go Start/ Programmes/ Accessories and find the command prompt icon. Hover the mouse over and right click, then select run as administrator. You can also make a desktop shortcut and right click / run as administrator from there.

If you don't run the command as administrator you receive the following error:

C:\Users\Admin>ipconfig/flushdns
The requested operation requires elevation.

Mark

[Rock]

That is one of the good reasons I hate Vista Read further here : http://www.eukhost.com/forums/f17/grr-vista-6273/

[danwall]

The same thing happens in Windows 7, you can simply click the start menu and type cmd to search for the command prompt, right click and and choose to run as administrator also - don't have to search through the various sub menus.