Facebook users experienced some unexpected downtime yesterday, due to an unplanned site outage. The site released a statement explaining that there had been a change to their DNS infrastructure, resulting in a lack of connection for some users. So – what does ‘DNS infrastructure’ actually mean, and why would it cause an outage?
Facebook Down: The Statement
“Earlier today we made a change to our DNS infrastructure and that change resulted in some people being temporarily unable to reach the site. We detected and resolved the issue quickly, and we are now back to 100 percent. We apologize for any inconvenience” – Mashable.
DNS: How Does it Work?
The Domain Name System or DNS is basically a method of organizing the Internet and connecting users (you) to web pages (Facebook) in the simplest way possible. Each website is hosted on a server, and has a unique IP (Internet Protocol) address. This address doesn’t look like your home address; it’s a series of numbers that looks a little like this: 220.127.116.11. If you know the IP address of your favorite website, you can put that series of numbers in your browser instead of the www.url.com and go directly to the site – bypassing the DNS servers entirely.
DNS Servers translate the web address we type into our browser address bar into the proper IP address, and deliver our request to the server at the destination we’ve requested. “Hey, Facebook, can I see my cousin’s new baby now?” If there’s any error in the address, our request doesn’t get delivered, and we don’t get to see the page we’re looking for. So, what can go wrong?
Facebook actually has whole series of IP addresses, like most large companies, and each is assigned or not assigned based on their client/server organizational plan, or DNS infrastructure.
Any change to the allocation of IP addresses in their system would immediately affect any users attempting to connect via those servers – they simply would be unable to connect. Imagine a mail carrier bringing your mail to find that your family had moved, and taken your entire house with you.
That’s similar to the result that you’ll experience when there’s a problem with the DNS – no forwarding address, and no existing home. All communication goes to the ‘dead letter office’ of the Internet: a blank page or connection error.
When Facebook Goes Down
If Facebook goes down again due to a DNS error, simply plug their current IP address into your browser’s address bar instead of www.facebook.com. Input 18.104.22.168 and you can connect easily, regardless of DNS issues.
Bear in mind, however, that web addresses change; if the house has moved, you’ll need to look up the new IP with a quick ‘ping’ of the site. Search for ‘cmd’ and open the program on your Windows computer, and type ‘ping www.facebook.com’ to see the current status of the site. For now, it appears to be up – and that’s a good thing… right?
Taylor, C. Facebook is Down for Some Users. (2012). Mashable. Accessed December 11, 2012.
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