When an Auto Scaling group is running in Amazon Elastic Compute Cloud (EC2), your application rapidly scales up and down in response to load within a 10-minutes window; however, after the load peaks, you begin to see problems in your configuration management system where previously terminated Amazon EC2 resources are still showing as active.
What would be a reliable and efficient way to handle the cleanup of Amazon EC2 resources with your configuration management systems? Choose 2 answers
A . Write a script that is run by a daily cron job on an Amazon EC2 instance and that executes API Describe calls of the EC2 Auto Scaling group and removes terminated instances from the configuration management system
B . Configure an Amazon Simple Queue Service (SQS) queue for Auto Scaling actions that has a script that listens for new messages and removes terminated instances from the configuration management system
C . Use your existing configuration management system to control the launching and bootstrapping of instances to reduce the number of moving parts in the automation
D . Write a small script that is run during Amazon EC2 instance shutdown to de-register the resource from the configuration management system
E . Use Amazon Simple Workflow Service (SWF) to maintain an Amazon DynamoDB database that contains a whitelist of instances that have been previously launched, and allow the Amazon SWF worker to remove information from the configuration management system
Answer: A,D