When AWS us-east-1 (North Virginia) goes down, the internet feels it — even in Europe.
But why does an outage thousands of kilometers away take down services running in eu-west-1 or eu-central-1?
The answer reveals a subtle but critical weakness in how cloud infrastructures are often configured.
A Single Region, Global Consequences
The us-east-1 region is AWS’s oldest and most deeply integrated environment. Many “global” AWS services such as IAM, Route 53, CloudFront, Certificate Manager, and Cognito still rely on infrastructure hosted there.
This means that even if your workloads live in Europe, your authentication, DNS resolution, or certificate validation might still depend on us-east-1. When that region goes down, your app in Dublin or Frankfurt can fail too.
The Hidden Misconfiguration
Developers and architects often fall into a trap: leaving the AWS SDK or console on its default region us-east-1.
It’s convenient, but it quietly centralizes critical services in one location.
Examples include:
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Lambda functions in Europe calling APIs in us-east-1.
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Global S3 buckets created without regional isolation.
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Identity and permission systems (IAM/Cognito) tied to one region.
This design leads to a single point of failure disguised as “global connectivity.”
Lessons for a More Resilient Cloud
At Pablosec, we’ve seen this pattern repeatedly and we’ve learned that resilience starts with awareness.
Here are key takeaways:
- Explicitly define your region — never rely on defaults.
- Use regional endpoints — for S3, API Gateway, and other services.
- Decouple authentication — replicate IAM roles or use regionally redundant Cognito pools.
- Test for regional isolation — simulate a us-east-1 outage in your DR drills.
- Map your dependencies — know which control-plane services your app touches.
🚨 The Bigger Picture
A resilient architecture isn’t just about uptime it’s about autonomy.
If your European business stops because North Virginia goes offline, that’s not AWS’s fault it’s a design flaw.
At Pablosec, we help organizations detect, isolate, and redesign such weak points in their cloud infrastructure.
Because in cybersecurity and cloud resilience, defaults are the enemy of control.
