A DevOps engineer must install a software package on 30 on-prem VMs and 15 EC2 instances, ensure the process is auditable, and automatically detect and alert on configuration drift. The environment is connected via AWS Direct Connect. Which solution provides the most operational efficiency?

Installing the SSM Agent on all VMs (both on-premises and EC2) allows AWS Systems Manager to manage them as a single fleet. Systems Manager State Manager can then be used to define and enforce the desired package installation, ensuring it's present and automatically re-applying if it drifts. AWS Config can monitor for configuration changes on both EC2 instances and on-premises servers (via Systems Manager integration), detecting drift from desired states. Amazon SNS can then be used to send notifications when drift is detected, providing an auditable, automated, and efficient solution. The other options are less efficient: Scripting weekly checks is reactive and doesn't provide real-time drift detection or centralized management. A script that produces a noncompliant list still requires manual intervention, which is inefficient and prone to errors. Manually logging into each VM is highly inefficient and not scalable, and while AWS Config can monitor AWS resources, it needs integration with Systems Manager for on-premises drift detection.