About application alerts

Application health is a reflection of the status of one or more of its application services. Application health is displays the status of application service with the most critical health. Once you select an application, you can view which application service(s) is affected.

Application service health is displayed based on the most critical status detected. There are two factors used to indicate changes in health:

The status of the virtual server connected to the application service. The health status of a virtual server is reflected by its communication with the server pool to your managed application. For more information about these alerts, see Virtual server status events, Wide IP status events, and Pool member status events.
A performance metric threshold is crossed and sustained over time. These are based on the metric conditions configured to your application service's alert rules.

Performance alerts are triggered by threshold violations, reported by application services. Active alerts reflect an ongoing application service performance issue. You can edit these thresholds, based on your system monitoring requirements.

A critical, or warning alert, that is active, indicates there has been a sustained threshold violation for over five minutes. A subsequent alert is triggered once another threshold is crossed (either an increase or decrease in severity, or cleared). To ensure that conditions are improving, an alert for declining severity (critical to warning) or a cleared alert, is triggered only when the value is sustained for five minutes at ten percent below the threshold value. For example, if a threshold value is configured for greater than 60 percent, a declining severity must be sustained at 54 percent or less to trigger an alert.

Security alerts are provided to applications and virtual servers with Web Application Security protection. These alerts vary based on the protection mode (blocking vs transparent). Security alerts differ from other alerts, as they are based on set thresholds, and they do not directly impact application health.