Non-Geeky Guide to Flushing DNS on Different Operating Systems

When tech people start talking about flushing DNS, Domain Name Servers, DNS cache problem, IP addresses, and all that techno mumbo jumbo stuff, it almost sounds like a bunch of aliens talking about different ways to operate on a live human brain–well, something like that. Anyway, in case you have a computer that has problems opening web pages while the rest of the computers on the same network don’t have issues then you better bring out your inner geek because you’re going to have to flush DNS to solve this issue.

It’s All Very Simple, Really

You don’t really have to freak out when you read about dealing with something called a DNS. Well for starters it isn’t a contagious disease that was mentioned in the latest Center for Disease Control Bulletin. The term is actually an acronym for Domain Name Server. That is actually one piece of human computer technology that makes things a lot easier for everyone.

Always remember that computers do a better job at talking with numbers. In contrast, bringing out the inner geek by the way, human beings are better at making descriptive communication. We’re a lot better at stating our messages using words. Now, to cover for the discrepancy between human language and the language spoken by machines like your Smartphone, laptop, or iPad, humans have invented the Domain Name Server or DNS or Domain Name System.

To make things simpler, you can think of it as a smart aleck way of saying that I can translate human language into machine language. That is exactly what the DNS does, it translates human language like “www.google.com” (anyone who has ever used a computer should know what that is by now) into some sort of number series called an IP address, such as 74.125.71.105. It should be pretty obvious that remembering web addresses is a lot easier than remember a series of numbers.

Computers usually make a list of IP addresses and their corresponding web addresses. But sometimes things get messed up so they need to start all over again from scratch. To erase all the messed up info they have gathered about these web addresses and the like, we need to issue commands that flush DNS. And here’s how you do that in various operating systems we use today.

Flush DNS in Windows

To do just that in a computer that runs a version of Windows operating system, you need to launch a command prompt. In case you’re using Windows 7 or Windows Vista you may have to run the command prompt as an administrator. You do that by going through Start > Programs > Accessories > and then right click on the command prompt icon and select run as administrator.

If you try to flush the DNS cache without doing that in these two later versions of Windows you will get this error message “The requested operation requires elevation.” It only means that you have to perform the operation as a computer administrator.

So, at the command prompt type: “ipconfig /flushdns” and then press enter – that’s it. Your computer will then tell you that it has cleared the DNS cache.

Flush DNS in Linux

You will do something similar when you’re working on a Linux machine. You have to log into your machine’s shell and type: “root@support [~] # cd /etc/rc.d/init.d” followed by “root@support [/etc/rc.d/init.d]#. /nscd restart” and that’s it.

Flush DNS in Mac OS

There is a slightly different way to do it when you’re working with Mac OS. If you have Tiger Mac on your machine then you need to issue a “$ lookupd –flushcache” in your terminal. Now, if you’re running Leopard Mac you need to issue “$ dscacheutil –flushcache” on your terminal window. And that’s basically how you flush the DNS cache on various operating systems.

Charlie is a free lancer writer and content builder of many Technology sites and has written many useful genuine articles.