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AWS Certified Solutions Architect - Associate Exam Question Walkthrough
Learn how to tackle a common AWS exam question regarding scaling applications on AWS, focusing on the best service choice.
Migrating applications to AWS can be tricky. Candidates often stumble over the choices for scaling solutions. The right decision impacts both performance and cost.
The question
A company is planning to migrate their on-premises application to AWS. The application experiences variable loads throughout the day, with peaks during business hours. They need a solution that can automatically scale based on demand and minimize costs. Which AWS service should they use?
- A. Amazon EC2 with Auto Scaling
- B. AWS Lambda
- C. Amazon ECS with Fargate
- D. Amazon RDS with Read Replicas
Think before you scroll
Consider the application's load patterns and the need for both cost efficiency and scalability. Each option has its strengths, but only one directly addresses the requirement for automatic scaling based on variable loads.
The answer
The correct option is A: Amazon EC2 with Auto Scaling. This service allows the application to automatically adjust its capacity based on current demand, scaling out during peak hours and scaling in during off-peak periods. This feature helps minimize costs while maintaining performance.
Why the other options lose
- B: AWS Lambda - While AWS Lambda offers serverless execution and is cost-effective for certain workloads, it may not be suitable for all application types, especially those requiring a persistent state or specific runtime environments.
- C: Amazon ECS with Fargate - ECS with Fargate is designed for containerized applications. While it can scale, it may not be the best fit for applications that need to run in a more traditional EC2 environment with specific scaling requirements.
- D: Amazon RDS with Read Replicas - This option focuses on scaling database operations rather than application load. It does not provide a solution for application-level scaling, which is essential in this scenario.
The concept behind it
The key principle here is understanding how different AWS services respond to varying workloads. Auto Scaling with EC2 is designed specifically for applications that require dynamic adjustment to their compute resources based on demand. This principle applies across many AWS services, where scaling capabilities can significantly impact performance and cost.
Exam trap to remember
Always prioritize options that provide automatic scaling for variable workloads. If the question emphasizes cost and demand fluctuations, look for services that directly address those needs.