Facebook (FB), Instagram and WhatsApp all suffered outages midday Monday, according to public statements from the three Facebook services.
The three apps – which are all owned by Facebook, and run on shared infrastructure – stopped working shortly before 5pm. Other related products, such as Facebook Messenger and Workplace, have also stopped working.
“We’re aware that some people are having trouble accessing our apps and products,” Facebook said on Twitter. “We’re working to get things back to normal as quickly as possible, and we apologize for any inconvenience.”
Outage tracking site Down Detector logged tens of thousands of reports for each of the services. Facebook’s own site would not load at all for about an hour on Monday; Instagram and WhatsApp were accessible, but could not load new content or send messages.
The reason for the outage was not immediately clear. However, multiple security experts quickly pointed to a Domain Name System (DNS) problem as a possible culprit. Around 1 pm ET, Cisco’s internet analysis division ThousandEyes said on Twitter that its tests indicate the outage is due to an ongoing DNS failure. The DNS translates website names into IP addresses that can be read by a computer. It’s often called the “phonebook of the internet.”