Facebook says widespread outage caused by router configuration changes had ‘cascading effect’

• Facebook said changes to its “backbone routers” caused Monday’s widespread outage.
• Facebook said it had “no evidence that user data was compromised” as a result of the outage.
• The global outage impacted all of Facebook’s apps and even internal communications.
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Facebook published a brief blog post Monday evening attributing the massive global outage that took its services and internal communications tools offline for several hours to a “faulty configuration change” to its routers.

“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,” Facebook Vice President of Infrastructure Santosh Janardhan wrote in the post.

“The underlying cause of this outage also impacted many of the internal tools and systems we use in our day-to-day operations, complicating our attempts to quickly diagnose and resolve the problem,” Janardhan added.

Facebook said it had “no evidence that user data was compromised as a result of this downtime.”

The post confirmed that Facebook’s services are “back online” and apologized for the inconvenience.

The outage impacted Facebook and all of its most widely used apps, including Instagram, WhatsApp, and Messenger.

Some services appeared to be back online for some users about 6 p.m. ET.

In the meantime, the outage wreaked havoc for influencers and businesses who rely on the platforms, users from across the world, and shareholders including CEO Mark Zuckerberg.