SAA-C03 Q384 · Scaling

Question

A company runs Amazon EC2 instances as web servers. Peak traffic occurs at two predictable times each day. The web servers remain mostly idle during the rest of the day. A solutions architect must manage the web servers while maintaining fault tolerance in the most cost-effective way. Which solution will meet these requirements?

Accepted Answer

**Option A: EC2 Auto Scaling group** satisfies every requirement:

1. **Manages web servers**: Auto Scaling groups automatically launch and terminate EC2 instances based on scaling policies, reducing manual management overhead.

2. **Fault tolerance**: Auto Scaling groups distribute instances across multiple Availability Zones. If an instance becomes unhealthy, the group automatically replaces it. This is a built-in fault tolerance mechanism.

3. **Cost-effective**: Since traffic peaks at two predictable times, Auto Scaling can use **scheduled scaling policies** (scale out before known peaks, scale in after) or **target tracking / step scaling policies** (react to CloudWatch metrics like CPU or request count). During idle periods, the group scales down to a minimum number of instances, so

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📘 Key Concepts

🏗️ Architecture

⚙️ Operations

💰 Cost

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