AWS Certified Solutions Architect – Associate (SAA-C02) — Question 534

A company runs a three-tier web application in a VPC across multiple Availability Zones. Amazon EC2 instances run in an Auto Scaling group for the application tier.
The company needs to make an automated scaling plan that will analyze each resource's daily and weekly historical workload trends. The configuration must scale resources appropriately according to both the forecast and live changes in utilization.
Which scaling strategy should a solutions architect recommend to meet these requirements?

Answer options

• A. Implement dynamic scaling with step scaling based on average CPU utilization from the EC2 instances.
• B. Enable predictive scaling to forecast and scale. Configure dynamic scaling with target tracking.
• C. Create an automated scheduled scaling action based on the traffic patterns of the web application.
• D. Set up a simple scaling policy. Increase the cooldown period based on the EC2 instance startup time.

Correct answer: B

Explanation

Predictive scaling analyzes historical workload trends to forecast future traffic and proactively scale resources ahead of time. Pairing it with target tracking dynamic scaling allows the Auto Scaling group to also handle unexpected, live fluctuations in real-time utilization. Other options, such as simple, step, or scheduled scaling, lack the ability to combine predictive modeling with real-time target tracking.