SAA-C03 Q248 · Scaling

Question

A company is migrating a distributed application to AWS. The application serves variable workloads. The legacy platform consists of a primary server that coordinates jobs across multiple compute nodes. The company wants to modernize the application with a solution that maximizes resiliency and scalability. How should a solutions architect design the architecture to meet these requirements?

Accepted Answer

**Answer B** satisfies every requirement:

1. **Modernization**: The primary server (coordinator) is replaced by **Amazon SQS**, a fully managed message queue. This eliminates the single point of failure that the legacy primary server represents. Producers submit jobs to SQS, and compute nodes pull jobs from the queue — no coordinator needed.

2. **Maximizes Resiliency**: SQS is a fully managed, highly available, distributed service. Messages are stored redundantly across multiple AZs. If a compute node fails mid-processing, the message becomes visible again after the visibility timeout expires, ensuring no job is lost. There is no single point of failure.

3. **Maximizes Scalability**: Auto Scaling based on **queue depth** (ApproximateNumberOfMessagesVisible) is the gold-standard pattern

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📘 Key Concepts

🏗️ Architecture

⚙️ Operations

💰 Cost

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