Users around the world probably noticed the massive Facebook outage on Monday, October 4, 2021. If you’re a regular user of Facebook, Instagram, Messenger, WhatsApp, or Oculus, then you were probably affected.
There were many rumors circulating around the Internet as to what was causing the problem. Everything from an expired domain to a hacker attack was blamed for the outage, but ultimately, indications were pointing to a DNS error due to improper BGP routing.
What are DNS and BGP?
DNS is short for Domain Name System (or Domain Name Server) and is the method by which domains (like facebook.com) are translated into Internet Protocol (IP) addresses. DNS basically works like a directory, pointing domain names to the IP addresses of servers on the Internet. When DNS fails, traffic cannot be routed to the servers.
BGP is short for Border Gateway Protocol and is the method that allows Internet traffic to be routed most efficiently from your computer or device to a server. BGP isn’t necessarily the shortest route between two points, but rather the best route. BGP determines the way that traffic flows across the Internet. Think of BGP as “Internet Magic.” If a problem occurs with the various BGP routers owned and managed by large companies and ISPs, then major problems can result.
Rumors and Speculation
It is believed that the problem was caused when Facebook engineers pushed out an update to their routers. Facebook was apologetic (via Twitter) to its users and customers, many of whom rely on the services for sharing content, communicating with friends & family, and advertising their businesses.
A report from Ars Technica said that a Facebook employee on Reddit stated that a config change to Facebook’s routers “inadvertently locked the employee out, meaning that the fix must come from data center technicians with local, physical access to the routers in question.”
In addition to being locked out of their own routers, Facebook employees seem to have been locked out of the building, too. The outage also affected logins for many websites that utilize Facebook’s Login feature for their websites or apps.
Of course, this all comes on the heels of the bombshell CBS 60 Minutes interview on Sunday night with Facebook whistleblower Frances Haugen. Naturally, some people online speculated that the more than six-hour outage was a deliberate attempt by Facebook to redirect the story, although this is highly unlikely. Haugen will appear before a U.S. Senate today to further discuss details of the company’s position of profits over safety.
The outage was also a major financial punch to Facebook. Estimates of lost ad revenue vary between $60 and $160 million. Mark Zuckerberg personally took a financial loss of over $6 billion as his company’s stock tumbled during the outage.