You are trying to use the AWS Systems Manager run command on a set of Amazon Linux AMI Instances. The run command is not working on a set of Instances. What can you do to diagnose the issue? (Select TWO.)

Answer options:

A.Ensure that the SSM Agent is running on the target machine.
B.Check the /var/log/amazon/ssm/errors.log file.
C.Ensure the right AMI is used for the Instance.
D.Ensure the security groups of the instances allow the incoming traffic from port 22.

Answer: A and B
Option A is CORRECT because the first step to troubleshoot the run command issue would be to check if the SSM agent is properly running on the target machine.
Option B is CORRECT because the SSM Agent stores logs in /var/log/amazon/ssm/errors.log. The information in these log files can help you to troubleshoot problems. 
Option C is incorrect because the right AMI has nothing to do with the issues. The agent which is used to execute run commands can run on a variety of AMIs.
Option D is incorrect because port 22 is not used for the run command in AWS Systems Manager.
For more information on troubleshooting AWS SSM, kindly visit the following URL:
https://docs.aws.amazon.com/systems-manager/latest/userguide/troubleshooting-remote-commands.html