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Exam Question Walkthrough: Cost-Effective AWS Solutions
Master the AWS Certified Solutions Architect - Associate exam with this question walkthrough focusing on cost-effective solutions for high availability.
A common challenge in the AWS Certified Solutions Architect - Associate exam is balancing cost and availability. Candidates often struggle to identify the most economical yet efficient combination of services. This question tests that balance directly.
The question
A startup is deploying a web application using AWS services. They want to minimize costs while ensuring high availability. Which combination of services is the most cost-effective solution for hosting the application?
- A. Amazon EC2 with Auto Scaling and Load Balancing
- B. AWS Elastic Beanstalk with a single environment
- C. AWS Lambda with Amazon API Gateway and DynamoDB
- D. Amazon Lightsail for web hosting
Think before you scroll
Consider how each option addresses both cost and availability. Focus on the pricing model of the services and how they scale with demand. High availability often comes with a higher price tag if not managed properly.
The answer
The correct option is C. AWS Lambda with Amazon API Gateway and DynamoDB. This combination minimizes costs since AWS Lambda charges only for the compute time used. It also scales automatically, making it suitable for variable workloads, which aligns with the startup's goals.
Why the other options lose
- A. Amazon EC2 with Auto Scaling and Load Balancing: This option incurs costs for running instances and load balancers. Although it provides scalability, the expenses can quickly add up, especially for a startup trying to minimize costs.
- B. AWS Elastic Beanstalk with a single environment: This solution may lead to unnecessary resource allocation. While it simplifies deployment, the costs associated with running an entire environment may not be justified for all applications.
- D. Amazon Lightsail for web hosting: While Lightsail offers a simplified hosting solution, it lacks the scalability features required for high availability. This can be a significant drawback for applications expecting varying levels of traffic.
The concept behind it
The key principle here is understanding the pricing and scaling capabilities of each service. AWS Lambda and API Gateway offer a pay-as-you-go model, making them ideal for applications with fluctuating usage. In contrast, services like EC2 or Elastic Beanstalk may require a more significant upfront investment, which is not always feasible for startups.
Exam trap to remember
Remember: when aiming for cost-effectiveness and availability, always evaluate the scaling model and pricing structure of the services in question. AWS Lambda often stands out as a cost-efficient choice for variable workloads.