[Bamboo Knowledge Base]
If you restart your Bamboo server without shutting down your elastic instances first, your elastic instances will continue to run. Your elastic instances will also be orphaned from your Bamboo server, and you will not be able to shut them down via Bamboo after your Bamboo server has restarted. You will need to terminate them via the Amazon Web Services (AWS) Console.
To shut down an elastic instance via the AWS Console:
Screenshot: Shutting down an elastic instance via the AWS Console