Configuring trigger conditions for link performance alerts

Link performance alerts are metric alerts that operate on a set of predefined dimensions and metrics that report on link utilization.

Open the Triggering and propagation settings screen

  1. Open the Alert management screen.

    All NAM alert management starts with the Alert management screen.

  2. Navigate to the Basic alert settings page of the alert wizard.

    • To edit an existing alert, select the alert you want to edit and then click the Edit Alert button.
    • To create a new alert from scratch, click the Add Alert button.
    • To clone an existing alert and edit the clone, select Actions ► Duplicate alert for the existing alert.
  3. Make any changes you want to basic settings and then click Next.
    The Triggering and propagation settings page of the alert wizard is displayed.

  1. Optional: Specify a dimension filter. By defining filters, you narrow down the applicability of the alert to a specific dimension or to a range of dimensions. For a link performance alert, you can filter traffic on the following dimensions:

    • Link name The name of the monitored link as visible on the Link View Status - Links CAS report.
    • Link type The type of the monitored link as visible on theLink View Status - Links CAS report.
    • Link alias The alias of the monitored link as visible on the Link View Status - Links CAS report.

    To add a dimension filter:

    1. Click Add iconAdd filter to add a filter selection box to the Dimension filters section.
    2. Hover the mouse pointer over the dimension name to display a complete dimension list.
    3. Select a dimension from the list.
    4. Define a filter expression. For information about filter syntax, see Filtering on text fields.
  2. Define alert triggering conditions.

    1. Specify the alert mode.
      Before you define the alert triggering conditions, you need to specify a number of generic detector settings for an alert (for example, the type of traffic to which the alert would be applied) or

      • Choose which value (current or baseline) of metrics describing the traffic should be compared with the thresholds you will define. The current or baseline value refers to one of the four metrics for a selected traffic type:
        • Incoming bytes
        • Outgoing bytes
        • Incoming utilization
        • Outgoing utilization
      • Specify the time frame—the number of intervals or minutes—for which the current or baseline metric values should be calculated.
      • Decide on the traffic type—link usage traffic or SNMP (router-related) traffic—to which the alert should be applied.
      • Specify if the alert should be raised when the current or baseline value of one of the above metrics exceeds the threshold for traffic going in at least one direction (incoming or outgoing), or in both directions at the same time.
    2. Define triggering condition details. You can define a maximum of four conditions that will describe when exactly the alert should be raised: two for incoming traffic and two for outgoing traffic. By default, all conditions are disabled.

      Minimum incoming threshold Minimum incoming utilization or volume. If the value of the selected metric falls below this threshold, the alert is raised. If you do not want an alert to be raised for low utilization or volume, leave this condition disabled.

      Maximum incoming threshold Maximum incoming utilization or volume. If the value of the selected metric exceeds this threshold, the alert is raised. If you do not want an alert to be raised for high utilization or volume, leave this condition disabled.

      Minimum outgoing threshold Minimum outgoing utilization or volume. If the value of the selected metric falls below this threshold, the alert is raised. If you do not want an alert to be raised for low utilization or volume, leave this condition disabled.

      Maximum outgoing threshold Maximum outgoing utilization or volume. If the value of the selected metric exceeds this threshold, the alert is raised. If you do not want an alert to be raised for high utilization or volume, leave this condition disabled.

  3. Optional: Switch to the Output filters tab to configure additional filtering rules. You can set additional conditions on metric alert output fields, so that only alerts satisfying these conditions are raised. For an explanation of how the output filters work, refer to Configuring Output Filters for Link Performance Alerts.

  4. Modify default alert propagation settings. This is done on the Propagation settings tab. By default, the alert is raised after one interval in which the defined conditions are met and lowered after one interval during which the conditions are not fulfilled, but you can change this setting and also specify when the alert should be re-issued or canceled. Additionally, you can define additional messages that are appended to the main notification message whenever a specific event occurs. For more information, see Modifying Alert Propagation Settings.

  5. Click Next to configure alert notifications. For more information, see Alert Notifications.