Troubleshooting AWS Systems Manager (SSM)

For AWS Systems Manager (SSM), if you cannot access an instance, you must investigate the following potential causes:

• Permissions: Check if the user or role has the required SSM permissions. If not, you need to add them.
• SSM Agent: Check if the SSM agent is running in the instance. Even if the SSM agent is running, verify if it has the correct permissions. You can know this by checking the SSM console in AWS. If not, it must be installed and running. This is part of the default Amazon Linux 2 AMIs (Amazon Machine Images). Other AMIs vary. You must also add the SSM permissions to the profile for the instance.
  • The Agent must also support the sessions, which it usually does, unless it is really old.

• Supported OS: Linux, BSD and Windows platforms are scanned.

If you test an AWS credential, the system reports which services can be accessed. For SSM, the system also checks the session permissions specifically, which will tell you if the user or role has permissions.