Push notifications allow stakeholders to be notified of important activities of the Controller, even when they are not logged into the NSX Advanced Load Balancer application. The notifications are sent through mediums like email, external logs, and so on and are configured to be triggered based on evaluation of metrics parameters or changes in their values.
Alert Configurations are used to define triggers that will generate an alert. For a detailed explanation on alert configurations, see Alert Config.
For more information on evaluating metrics, see Controller Metrics and User-defined Metrics.