AWS Certified Solutions Architect – Associate (SAA-C03) — Question 688

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 uses machine learning to analyze historical traffic patterns and proactively scale resources ahead of forecasted demand, satisfying the requirement to analyze daily and weekly trends. Combining this with dynamic scaling using target tracking ensures the Auto Scaling group can also react to sudden, unexpected real-time changes in utilization. Other options, like simple, step, or scheduled scaling alone, do not combine both predictive forecasting and real-time adaptive scaling.