We now know why the DNS failed

AWS’s big outage on October 19, 2025 knocked services offline for over 24 hours—and after a 10-day wait, the official root-cause analysis finally explains what went wrong.

It turns out a DNS configuration mix-up in Dynamo kicked off a domino effect, triggering EC2 errors and Network Load Balancer failures that cascaded through AWS’s backbone. The detailed RCA breaks down each misstep so you can see exactly how one glitch spiraled into a full-blown day-long outage.

Watch on YouTube