Starting with Ambari 2.0, Ambari includes built-in systems for alerting and metrics collection. Therefore, when upgrading to Ambari 2.1, the legacy Nagios and Ganglia services must be removed and replaced with the new systems. You only need to perform these steps and migrate to Ambari Alerts and Metrics if you are running Nagios and Ganglia.

	Important
	We highly recommended that you perform and validate this procedure in a test environment prior to attempting the Ambari upgrade on production systems.