Which combination of steps should the solutions architect take to troubleshoot this issue?
(Choose two.)
Verify that Systems Manager Agent is installed on the instance and is running.
Verify that the instance is assigned an appropriate IAM role for Systems Manager.
Verify the existence of a VPC endpoint on the VPC.
Verity that the AWS Application Discovery Agent is configured.
Verify the correct configuration of service-linked roles for Systems Manager.
Explanations:
The Systems Manager Agent (SSM Agent) must be installed and running on the EC2 instance for it to appear as a managed instance in AWS Systems Manager. If the agent is not installed or not running, the instance will not be able to communicate with Systems Manager.
The EC2 instance must have an IAM role with appropriate permissions to allow Systems Manager to manage the instance. Without the correct IAM role, the instance will not be able to register with Systems Manager.
While a VPC endpoint for Systems Manager can facilitate communication without going over the internet, the primary requirements for an instance to appear as a managed instance are the SSM Agent and the correct IAM role. A VPC endpoint is not necessary for public instances.
The AWS Application Discovery Agent is not related to Systems Manager’s management of EC2 instances. It is used for collecting information about on-premises servers and applications for migration purposes, and does not impact whether an instance appears in Systems Manager.
Service-linked roles for Systems Manager are important for allowing AWS to manage resources on behalf of the user, but they do not directly influence whether an individual EC2 instance appears as a managed instance. The essential factors are the SSM Agent and the IAM role attached to the instance.
As I see it, the answer is:
Verify that Systems Manager Agent is installed on the instance and is running.