Amazon SSM Agent - Release 3.1.821.0 - 2022-01-13

• Implement new core module named MessageService to start processing commands from both MGS and MDS
  • Merge functionalities from RunCommandService core module and Session core module.
  • Receive run command documents through MGS if connected and fallback to MDS otherwise. This functionality requires appropriate permissions for both endpoints and will be rolled out gradually to end users.
  • Provide filesystem based idempotency check to avoid duplicate run command document execution.
  • Increase default run command pool buffer size from 1 to 5 to load additional documents before-hand for processing.
• Fix nil pointer deference panic produced in named pipe test case during agent update
• Remove StopType concept in ssm-agent-worker and add different waits for reboot and shutdown stop

Bugs:

• Version is affected by #436