Facebook, Instagram and WhatsApp back online after major outage
The fault affected more than 3 billion people and cost Mark Zuckerberg approximately $7 billion
Facebook, WhatsApp and Instagram are back up and running after being down for more than six hours in a major outage on Monday.
The three services - which are all owned by Facebook and run on shared infrastructure - stopped working shortly before 17:00 GMT. Users who tried to access these services through smartphone apps or over the web met error messages.
Other related products, such as Facebook Workplace and Messenger, also went down.
Outage detector service Downdetector said it was the largest failure it had ever seen, with more than 10.6 million issues reported worldwide.
Many of Facebook's internal tools and systems used in day-to-day operations - including door access badges - were also affected, complicating attempts to diagnose and resolve the issue.
The disruption lasted for nearly six hours, with users eventually beginning to regain access at around 23:00 GMT.
In a statement, Facebook said the outage occurred as a result of faulty configuration change.
'Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centers caused issues that interrupted this communication.
'This disruption to network traffic had a cascading effect on the way our data centers communicate, bringing our services to a halt.'
The firm added that there was no evidence to suggest that any user data was compromised as a result of the disruption.
Facebook apologised to all those affected due to the outage, saying it understands that such disruptions impact people's lives as well as business around the world.
This was the worst outage for Facebook since 2008, when a bug caused the social media service to remain offline for about a day, although the platform had just 80 million users at that time. Today, Facebook has nearly 3 billion users.
The disruption came a day after a Facebook whistleblower, who leaked a cache of internal documents about the company, alleged in an interview that the social media firm prioritised profit over public safety.
Frances Haugen, a former Facebook employee, said on CBS's 60 Minutes programme that the company's own evidence showed that it was lying to the public about making significant progress against misinformation, hate and violence.
Ms Haugen has filed a whistleblower complaint with the US Securities and Exchange Commission, alleging that Facebook misled investors about its actions.
She will testify before a Senate subcommittee today in a hearing about the Facebook's research into the impact of Instagram on the mental health of teenagers.