An application runs on EC2 instances behind an Application Load Balancer in an Auto Scaling group. Because the application scales out and in frequently, instance logs disappear after scale-in. How can the development team retain and view application logs after instances are terminated by scale-in events?

The correct solution is to configure EC2 instances to publish application logs to Amazon CloudWatch Logs using the unified CloudWatch agent. This ensures that logs are streamed off the instance in real time or near real time to a persistent, centralized logging service. Even if an instance is terminated during a scale-in event, its logs remain accessible in CloudWatch Logs, allowing the development team to view and analyze them. Enabling access logging on the Application Load Balancer only captures ALB access logs, not application-specific logs from the EC2 instances. Changing the Auto Scaling group to use a step scaling policy affects how scaling occurs, but it does not address the problem of ephemeral logs on terminated instances. Instrumenting the application with AWS X-Ray is for distributed tracing and performance analysis, not for collecting and retaining application logs.