SAA-C03 Question 246
Single answerA company runs a web application on Amazon EC2 instances behind an Application Load Balancer (ALB). Traffic to the application increases significantly during business hours, causing performance issues. The company wants to ensure the application automatically scales during traffic spikes while minimizing costs during idle times. What is the most appropriate solution to meet these requirements?
- A
Manually add or remove EC2 instances based on traffic patterns.
- B
Configure an Auto Scaling group with target tracking scaling policies based on the average CPU utilization of the EC2 instances.
- C
Use Spot Instances exclusively to handle traffic spikes and terminate them during idle times.
- D
Configure an Auto Scaling group with scheduled scaling policies to add and remove instances at fixed times.
Show answer and explanation
Correct answer: B
Explanation
To design a high-performing and elastic compute solution, an Auto Scaling group with target tracking scaling policies is the most appropriate choice. It dynamically adjusts the number of EC2 instances based on real-time metrics, such as CPU utilization, ensuring the application can handle traffic spikes while minimizing costs during low traffic periods. This approach aligns with AWS best practices for scalability and elasticity.
- A. Incorrect.
Manually managing EC2 instances is not efficient or scalable, especially during unpredictable traffic spikes, and does not align with the requirements for elasticity.
- B. Correct.
Using an Auto Scaling group with target tracking scaling policies ensures that EC2 instances are added or removed based on real-time metrics like CPU utilization, providing elasticity and cost efficiency.
- C. Incorrect.
Using Spot Instances exclusively is not suitable for consistent application availability as Spot Instances can be interrupted at any time. This does not guarantee handling of traffic spikes effectively.
- D. Incorrect.
Scheduled scaling policies can be useful for predictable traffic patterns but are not effective for handling unpredictable traffic spikes as described in the scenario.