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Summary
On Monday, October 4, 2021, Facebook suffered a prolonged outage when, during routine maintenance, all connections to their global backbone network were mistakenly taken down. More details on the cause and response to the outage are available on the Facebook blog.
At Netskope, we help secure the cloud and web traffic of millions of users worldwide. In this blog post, we provide a glimpse into what the Facebook outage looked like from our perspective. Information presented in this blog post is based on anonymized usage data collected by the Netskope Security Cloud platform relating to a subset of Netskope customers with prior authorization.
The Facebook Outage
What did Monday look like compared to a normal day? The figure below shows the average and standard deviation of the traffic to Facebook in gray. The blue line shows the traffic on October 4. At 15:39 UTC the outage begins, and we see a sharp decline in Facebook traffic that lasts for 5.5 hours.
Where did everyone go?
Without Facebook, what did everyone do? They spent the afternoon on Twitter instead. Traffic to Twitter saw a sharp increase in traffic at 15:39 that continued for the duration of the outage before returning to normal levels when Facebook came back online.
