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Cost-Optimized Architecture: A Walkthrough of a SAA-C03 Exam Question
Explore a key AWS exam question on cost optimization for EC2. Understand the correct approach and why other options fall short.
A common stumbling block for candidates is understanding how to effectively reduce costs while maintaining performance in AWS. This question tests your knowledge of cost optimization strategies, particularly in relation to EC2 instances.
The question
A company has a large number of virtual machines running on Amazon EC2. They want to reduce costs but maintain performance. Which approach would be the most effective for achieving a cost-optimized architecture?
A. Switch all instances to On-Demand pricing.
B. Utilize Reserved Instances for steady-state workloads.
C. Migrate all workloads to Amazon Lightsail.
D. Use AWS Batch to manage compute workloads.
Think before you scroll
Before jumping to the answer, consider the cost implications and usage patterns of the company’s EC2 instances. Look for options that align with steady-state workloads and long-term commitments to maximize savings.
The answer
The correct option is B: Utilize Reserved Instances for steady-state workloads. This approach allows the company to save significantly on costs by committing to a one or three-year term, which is ideal for environments with consistent usage.
Why the other options lose
A: Switch all instances to On-Demand pricing. While On-Demand pricing offers flexibility, it does not provide the cost savings that Reserved Instances do. This option fails to optimize costs for steady-state workloads.
C: Migrate all workloads to Amazon Lightsail. Although Lightsail is cost-effective for certain applications, it may not support all the workloads currently running on EC2. This option risks performance and compatibility issues.
D: Use AWS Batch to manage compute workloads. AWS Batch is primarily focused on managing batch jobs rather than directly reducing costs. It does not inherently optimize pricing for steady-state workloads like Reserved Instances do.
The concept behind it
The underlying principle here is understanding how to align pricing models with usage patterns. Reserved Instances are designed for steady-state workloads, providing significant savings over time. Recognizing the right pricing model for different workloads is crucial for cost optimization.
Exam trap to remember
Remember: For steady-state workloads, Reserved Instances are your best cost-saving option. Always assess usage patterns before choosing a pricing model.