Amazon Web Services faced a significant outage on Monday, affecting major websites and services like Facebook, Snapchat, and Coinbase. The incident raised concerns about the internet’s heavy reliance on the cloud giant.

The issues began in Amazon’s Northern Virginia region in the early hours of Monday, with a DNS resolution problem affecting DynamoDB. This failure impacted thousands of apps that rely on the service for data storage and retrieval.

Several services were affected by the outage, including OpenAI’s ChatGPT, check-in kiosks at LaGuardia Airport, financial apps like Venmo and Robinhood, gaming platforms such as Roblox and Fortnite, messaging apps like Signal, and productivity tools like Slack and Canva.

By 3:35 a.m., Amazon confirmed that the core DNS issue was resolved, and most services were back to normal. However, there were still some issues with Lambda and EC2 services that the company was addressing.

US-EAST-1, Amazon’s oldest and largest cloud region, has been a recurring source of outages over the years. The latest incident highlighted the need for better redundancy and backup plans for sites relying on AWS services.

Amazon later identified the root cause of the outage as an internal subsystem responsible for monitoring network load balancers. They continued to work on recovering affected services and implementing mitigations.

The outage was not a result of a cyberattack but underscored the potential risks of relying heavily on a single cloud provider for critical services.