In a recent blog post, Facebook identified a reason for its October 4 outage. Thousands of users reported Facebook, WhatsApp, and Instagram outages yesterday. According to Facebook, configuration changes on their routers caused the crash. The company says the outage affected its internal tools, causing a delay in diagnosing the issue.
Santosh Janardhan, VP, Infrastructure at Facebook, published the update. In the post, the company also emphasized no evidence of user data leaks during downtime. The October 4 outage lasted roughly around 6 hours. This was the worst Facebook outage since 2019, when the site was down for over 24 hours.
Here’s an excerpt from the company’s blog post on the recent outage:
Our engineering team has 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.
Facebook blog post on October 4 outage
While the post identifies the configuration changes as the cause of the breakdown, it also says that Facebook is “working to understand more about what happened.” Facebook founder and CEO Mark Zuckerberg also posted an apology about the outage.
