AWS US-EAST-1 Outage Disrupts Global Internet Services for Over 15 Hours

A significant outage in Amazon Web Services' (AWS) US-EAST-1 region on October 20, 2025, caused widespread disruption across numerous internet services globally, stemming from an error during a technical update to the DynamoDB API. The incident, which began around 11:49 PM PDT on October 19 (6:49 AM UTC on October 20), was primarily attributed to DNS resolution issues for DynamoDB's regional service endpoints, preventing proper translation of domain names to IP addresses and blocking connections. This critical failure in AWS's largest and oldest data center cluster led to cascading impacts on dependent services, including EC2 instance launches and Network Load Balancer health checks.

The root cause was identified as a technical update to the API of DynamoDB, a core AWS database service, which introduced an error that disrupted DNS resolution. According to the tweet summary, "This error disrupted DNS resolution for DynamoDB's regional service endpoints, preventing systems from properly translating domain names to IP addresses and thus blocking connections to the service." This foundational issue meant that many applications could not find the necessary IP addresses to connect to DynamoDB, leading to widespread service interruptions.

The outage's impact was extensive, affecting thousands of companies and millions of internet users across various sectors, including banking, social media, gaming, and government services. Major platforms like Snapchat, Reddit, WhatsApp, and even financial institutions and airlines experienced disruptions, underscoring the internet's reliance on AWS's infrastructure. US-EAST-1 serves as a critical hub, and its issues often lead to global repercussions due to dependencies from other regions and global AWS services.

AWS engineers mitigated the initial DNS problem by 2:24 AM PDT on October 20, but full recovery of all affected services, including processing backlogs, extended until approximately 3:01 PM PDT. The company confirmed increased error rates and latencies for multiple AWS services in the US-EAST-1 region during the event. AWS has indicated that a detailed post-event summary will be published to provide further insights into the incident.