AWS Certified SysOps Administrator – AssociateCost and Performance OptimizationEasy
A company operates a web application on Amazon EC2 instances behind an Application Load Balancer (ALB). The application experiences predictable daily traffic spikes between 9 AM and 5 PM, Monday to Friday. Outside these hours, traffic is significantly lower. The company wants to ensure optimal performance during peak times and minimize costs during off-peak hours. Which Auto Scaling Group feature should be used to manage EC2 instance capacity?
- ASimple Scaling Policy
- BStep Scaling Policy
- CTarget Tracking Scaling Policy
- DScheduled Scaling
Show answer & explanationAnswer & explanation
Correct answer: D. Scheduled Scaling
Scheduled Scaling allows you to set up a schedule for your Auto Scaling group to scale in or out at specific times. This is perfect for predictable traffic patterns like daily business hours, ensuring capacity is available when needed and scaled down during off-peak to save costs.
Why the other options are wrong
- A. Simple Scaling Policy adjusts capacity based on a single alarm threshold. It's reactive and doesn't handle predictable time-based changes efficiently.
- B. Step Scaling Policy adjusts capacity in steps based on alarm breaches. Like simple scaling, it's reactive to actual load, not predictable time-based changes.
- C. Target Tracking Scaling Policy adjusts capacity to maintain a specified metric (e.g., CPU utilization) at a target value. It responds to actual load, not predictable time-based changes.
Auto Scaling Scheduled Scaling
An Auto Scaling feature that allows you to scale your EC2 instances up or down based on a predictable schedule.
- Ideal for predictable traffic patterns (e.g., daily, weekly).
- Proactively adjusts capacity, reducing the need for reactive scaling.
- Helps optimize costs by scaling down during off-peak hours.
Memory trick: Scaling is smart: Schedule for certainty, track for trends.