Facebook was down all evening worldwide along with its associated apps Instagram and WhatsApp.
But what caused Facebook to go down for so long and with absolutely no access for anyone?
The reason has to do with complicated processes behind how the websites work on a technical level.
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Although it isn’t confirmed, tech experts think that Facebook’s DNS protocols – ie how Facebook’s data connects to users trying to find it – was taken offline, probably by accident although there is still an outside chance it relates to an attack.
Cloudflare senior vice president Dane Knecht said Facebook’s border gateway protocol routes had been “withdrawn from the internet.”
Experts say the code which tells servers where Facebook is – kind of like a postal address for computers – has been removed.
Therefore though Facebook’s app and website and all its data still exists, the servers that take users’ internet browsers and connect it to Facebook’s servers doesn’t know where Facebook, Instagram or WhatsApp are any more, or how to find their data.
However, the incident appears to be a mistake rather than an attack, these same experts say.
Matthew Prince said: “Nothing we’re seeing related to the Facebook services outage suggests it was an attack. Most likely explanation is that the company’s Internet routes (BGP) were withdrawn by mistake during maintenance.”
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Dane Knecht added: “After Facebook gets network back up I expect a long period of instability. Rebooting a distributed system of this size is hard. They will have cold caches and systems that need other systems to bootstrap.
“They will almost certainly try to start back up slowly. This is going to look like a huge ddos attack with every Facebook client, SDK, etc all trying to retry at once”
This of course, could prove not to be the case. But it seems that these tech gurus know what they are talking about.
If so, it explains why it took a lot longer than usual for Facebook to come back online.
Cyber security specialist Jake Moore said there is a “chance” the issue could be related to a cyber attack.
He said: “There have been many reports and I’m struggling to find out exactly what has happened- I’m reading it could be DNS related, which means there is an issue with the connection not knowing where to go to your device.
“It could well be a human error or a software bug lurking in the shadows but whatever it is Facebook needs to do its best to mitigate the problem of causing more panic about this.
“The biggest problem is fears over a cyber attack but as we saw from Fastly in the summer I would hedge my bets on that not being the case as we’re talking about one of the biggest companies in the world, but there’s always a chance.”
Facebook’s chief technology officer, Mike Schroepfer tweeted: “*Sincere* apologies to everyone impacted by outages of Facebook powered services right now.
“We are experiencing networking issues and teams are working as fast as possible to debug and restore as fast as possible.”
A Facebook company spokesperson added: “We’re aware that some people are having trouble accessing our apps and products.
“We’re working to get things back to normal as quickly as possible, and we apologise for any inconvenience.”
Speculations are rife as to what could have possibly caused the blackout.
UK Technology Editor at the Guardian Alex Hern has explained the problem in layman’s terms.
He wrote on Twitter: “Facebook (accidentally, we assume) sent an update to a deep-level routing protocol on the internet that said, basically, ‘hey we don’t have any servers any more xoxo’
“Normally, this would be quite easy to fix. you just send another update saying ‘oh, don’t worry, we have servers, they’re here, xoxo’. Things still break, it takes a while for the message to spread to all corners of the internet, egg on face, but liveable.
“but Facebook runs EVERYTHING through Facebook. So when its servers were booted off the internet, it also booted off… the ability to send that follow-up message
“and the ability to log-in to the system that would send the follow-up message. and the ability to use the smartcard door lock on the front door to the building that contains the servers that control the system that sends the follow-up message
“and the messaging service you use to contact the head of physical security to tell them they need to high-tail it to the data centre out east with a physical key to override the smartcard door lock on the front door…”