How to create an Auto Scaling Group

0-2 years experience

1. 1We need to spin up a web service behind a load balancer. How would you set up an Auto Scaling Group to ensure at least two instances are always running?
2. 2If you launch an ASG with a desired capacity of 3 but one instance fails health checks, what happens and how would you configure it to replace the instance automatically?
3. 3Can you walk me through the steps in the AWS console to create an ASG that uses a specific AMI and instance type?

2-5 years experience

1. 1Our traffic spikes during a marketing campaign and the existing ASG didn't scale out fast enough. How would you adjust the scaling policies to handle such bursts?
2. 2We noticed the ASG is terminating instances that are still processing requests. What could cause that, and how would you fix it?
3. 3Explain how you would use a launch template versus a launch configuration when creating an ASG, and why you might choose one over the other for a new feature rollout.

5-8 years experience

1. 1Design a multi‑AZ, multi‑region deployment that uses Auto Scaling Groups to provide high availability and disaster recovery. What are the key considerations and trade‑offs?
2. 2Our cost team wants to reduce EC2 spend while maintaining performance. How would you configure scaling policies, instance types, and lifecycle hooks to achieve cost optimization?
3. 3During a rolling deployment we need to replace all instances in an ASG without downtime. Describe the steps and any AWS features you would leverage.

8+ years experience

1. 1We are migrating a legacy monolithic app to a microservices architecture on AWS. How would you restructure existing Auto Scaling Groups to support independent scaling and deployment pipelines across many teams?
2. 2Explain how you would design a centralized scaling governance model that enforces policies such as max instance count and allowed instance types across dozens of ASGs owned by different product groups.
3. 3What would be your strategy for integrating Auto Scaling with a custom metrics system and ensuring consistent scaling behavior across multiple AWS accounts?