Commonly known as DNS, it’s like a phone book for the internet. It’s the tool that converts a web domain, like Facebook.com, into the actual internet protocol, or IP, address where the site resides. Think of Facebook.com as the person one might look up in the white pages, and the IP address as the physical address they’ll find.
On Monday, a technical problem related to Facebook Inc.’s DNS records generated at least six hours of outages. When a DNS error occurs, a user’s web browser or smartphone apps can longer navigate to Facebook services.
Not only did Facebook’s primary platforms down, but so too did some of its internal applications, including the company’s own email system. Users on Twitter and Reddit have also said that employees at the company’s Menlo Park, California, campus were unable to access offices and conference rooms that required a security badge. That could happen if the system that grants access is also connected to the same domain -- Facebook.com.
The problem at Facebook appears to have its origins in the Border Gateway Protocol, or BGP. If DNS is the internet’s phone book, BGP is its postal service. When a user enters data in the internet, BGP determines the best available paths that data could travel.
Seeing @Facebook's BGP announcements getting published again. Likely means service is on a path to getting restored.
— Matthew Prince
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