Facebook said Friday that users around the world were again having trouble accessing its services for hours on end as a result of a modification to its system, just days after a massive outage caused in a similar manner.
“Sincere apologies to anyone who has not been able to access our products in the past few hours,” a Facebook spokesperson told AFP at 21:30 GMT.
“We’ve solved the problem and everything should be back to normal now.”
Website trouble tracker DownDetector showed spikes in reports of problems accessing or using Facebook and its photocentric Instagram network, as well as Messenger and WhatsApp, which started about three hours earlier.
Facebook attributed the problems to a configuration change on its computing platform and said it affected users of the social network and Instagram, Messenger and Workplace worldwide.
People flocked to Twitter to express frustration.
“How’s Instagram going?” read a tweet with a photo of cartoon character Bart Simpson apparently sitting in a corner.
“It’s not even 4 days and it’s already down.”
“Again problems with Instagram, Facebook, Facebook Messenger and WhatsApp!” read a lament in a DownDetector chat forum.
Hundreds of millions of people were unable to access Facebook, Instagram or WhatsApp for more than six hours on Monday, highlighting the world’s reliance on the Silicon Valley giant’s platforms.
In an apologetic blog post, Santosh Janardhan, Facebook vice president of infrastructure, said the outage that day was caused by “configuration changes” on routers that coordinate network traffic between data centers.
Cyber experts think the problem has to do with something called BGP, or Border Gateway Protocol – the system that the Internet uses to choose the fastest route to move information packets.
Sami Slim of data center company Telehouse compared BGP to “the internet equivalent of air traffic control”.
In the same way that air traffic controllers sometimes make changes to flight schedules, “Facebook has updated these routes,” Slim said.
But this update contained a critical bug.
It’s not yet clear how or why, but Facebook’s routers essentially sent a message to the Internet announcing that the company’s servers no longer existed.
The outage on Friday had nothing to do with the one earlier in the week, according to Facebook.
Experts say Facebook’s technical infrastructure is unusually dependent on its own systems.
Social media outages are not uncommon: Instagram alone has experienced more than 80 in the United States in the past year, according to website builder ToolTester.
Facebook’s services are vital to many businesses around the world, and Facebook accounts are often used to log into other websites as well.
Facebook’s apps are used by billions of people every month, which means that outages can affect a large part of the world’s population.