The Domain Name System (DNS) is one of the pillars of the internet. Without it, the entire domain name system could not function and we would have to navigate the internet using «clean» IP addresses – it does not exactly define fun, if you ask me.
Every time you access a domain name, your system keeps a record of the IP addresses that those domains point to (this is called a cache). This whole process makes your next access to that domain much faster because it doesn't have to look it up again, which could take just a few seconds.
But sometimes your local domain name cache stops syncing with the actual direction of a domain name to an IP address. That's why you might find yourself unable to access a website, even if the website isn't down – especially if the website in question has recently changed servers.
When this happens, you need to flush your DNS cache. Fortunately, this can be done with a simple terminal command on Ubuntu and other Debian systems:
$ sudo /etc/init.d/dns-clean
Of course, there are other DNS-related tricks that you might actually find useful, such as optimizing your DNS for faster internet speeds and changing your DNS to improve online security . Stay tuned to Secnews for more DNS-related articles.
