What is the primary use of the Run Command feature in SSM?

The primary use of the Run Command feature in AWS Systems Manager (SSM) is to execute remote commands on instances. This functionality allows users to safely execute scripts or commands across a fleet of EC2 instances without needing to manually log in to each instance. It supports automation and management tasks at scale, enabling system administrators to deploy updates, configure applications, and gather information from instances remotely.

Run Command provides a way to run scripts or specific commands on one or multiple instances in a secure manner, integrating with AWS Identity and Access Management (IAM) for proper permissions and controls. This service is particularly useful for routine tasks like patch management, application management, configuration management, and other administrative activities.

In contrast, the other choices do not accurately reflect the primary function of the Run Command feature. For instance, while deploying applications on EC2 instances is a valid operation, it typically involves services like Elastic Beanstalk, CodeDeploy, or container orchestration, which are better suited for such tasks. Similarly, creating and managing templates for resources relates more to AWS CloudFormation, and monitoring costs connects to AWS Cost Explorer or Billing services, which are unrelated to the specific use of Run Command.