The following figure shows the Create Monitoring Plan page for a disk resource in OpenEdge Management. The Rule definition section contains the Alert if disk activity exceeds field, which is an example of a rule for which a polled alert is generated. The value defined for this threshold, along with the values defined for the associated action and alert fields in this same section, enable the triggering of a polled alert.
Figure 1. Sample polled alert-related data
The Monitoring plan definition section contains the Polling Interval field. Based on the value you define for this field, the resource is checked (polled) according to the time interval specified. The default value of 900 seconds as shown in Figure 1 establishes that this disk resource must be checked every 15 minutes and a count kept of the number of passed or failed polls. This count is used to assess the alert properties values defined in the Rule definition to determine when to throw or clear an alert. Note that the Alerts Enabled field is selected in Figure 1. Alerts fire when the resource is active and a rule is violated.
The Rule definition section shows the fields related to rules, alerts, and actions for a disk resource monitor. Note that the rule definition is actually a combination of the threshold value and the specific values related to actions and alerts that identify the activities performed if this threshold is exceeded.
As shown in the Rules definition section in Figure 1, polled alerts require you to either accept default values or set values in a combination of fields to establish the following criteria:
The specific rule's threshold which, when violated, causes an alert to trigger. In Figure 1, the rule threshold is set at 90.0% in the Alert if disk activity exceeds field.
The severity of the alert as defined in the Alert severity field: Informational, Warning, Error, or Severe. In Figure 1, the severity chosen is Error.
The number of polls in which the condition must occur before an alert is generated. In Figure 1, the Throw alert after field indicates that the alert will be generated after one failed poll.
When to throw additional alerts: after a clear, or after a certain number of failures.
The action, if one is specified, to perform in OpenEdge Management when the alert is generated.
The number of polls in which the condition must occur without the detection of any rule violations before the alert is automatically cleared. In Figure 1, the value of 0 in the Clear alert after field indicates that the alert will not be automatically cleared. (If you choose not to clear an alert automatically, you must clear it manually.) See Clearing alerts through the management console for more details about manually clearing alerts.
The action, if one is specified, to perform in OpenEdge Management when the alert is cleared.
The specific rule's threshold which, when violated, causes an alert to trigger. In Figure 1, the rule threshold is set at 90.0% in the Alert if disk activity exceeds field.