Detector settings precisely describe the conditions under which an alert is raised and lowered and when it expires.
This basic procedure applies to the following user-defined alert types:
- Dynatrace Synthetic Monitoring backbone
- Real user performance
- Synthetic and sequence
- Citrix/WTS hardware
- Network link
- Internetwork traffic For alerts related to link performance, follow the steps described in Configuring trigger conditions for link performance alerts.
To configure when an alert should be triggered:
Open the Triggering and propagation settings screen
- If you are not already there, open the Alert management screen.
- 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.
- Make changes to basic settings and then click Next.
The Triggering and propagation settings page of the alert wizard is displayed.
Specify which part of traffic you want to monitor with your alert
- Leave the dimension unselected (default setting). As a result, the thresholds are applied to the aggregated metric values for all dimensions and the notification also contains aggregated information for all dimensions (one entry). To learn how to modify the default settings and how this affects your alert definition, refer to Configuring optional alert detector settings.
- Leave the default dimension filter settings. The default dimension filters limit the conditions in which the alert is triggered to the real traffic type or to specific transaction source, depending on the alert type.
- Select a metric to which the alert will be applied.
Depending on the complexity of an alert, you can choose between the two options:
- In the Monitored metric section, select a metric from the predefined list. Apart from metric names, the list contains additional controls that enable you to change the default display settings, such as whether metric mnemonics (IDs) are displayed or whether are displayed in alphabetical order or in groups based on their function. For an explanation of all available metrics, see Metrics available for user-defined alert definitions
- Define a compound metric using the Compound metric builder. With the builder, you can define expressions composed of basic metrics and arithmetic operators. To define a compound metric:
- Open the metric list.
- Access the Compound metric builder from a the Build compound metric link that is available on the metric list.
- Click Add metric and select a metric from the list. Depending on the complexity of the expression you want to define, you need to add at least two metrics.
- Choose an arithmetic operator from the list.
The list includes addition “+”, subtraction “-”, division “/”, and a percentage value
%(quotient multiplied by 100). Only the addition “+” and subtraction “-” operators can be combined in the same expression.
- Click OK to save the configuration.
For example, define a metric to report the percentage of slow operations in all detected client operations. In the compound metric builder, first add and select the Slow operations metric, then add and choose Client operations, and then choose the
%operator and save the definition.
Specify the conditions under which the alert should be raised
The value of the selected metric is constantly monitored and compared against the thresholds that you define. If the conditions are met, the alert is raised. The thresholds can be either single values or ranges of values that are defined by specifying more than one condition.
Leave the default comparison mode settings. A comparison mode describes how the metric value should be compared against threshold value. There are three modes to choose from: single, absolute, and relative. The default is single mode, which works as follows:
- If only a value condition is specified, the current value of the metric being monitored is compared with a threshold value specified in this condition.
- If a baseline condition is specified, the current value of the metric is compared with the baseline value multiplied by the baseline multiplier . For more information, see Comparison modes overview.
Click Add condition. At least one condition must be set for an alert definition. Note that for an alert to be raised, all defined conditions must be fulfilled.
Choose a type for the newly added condition. There are three condition types: value, baseline, and cut-off. Note that depending on other detector settings, some condition types may not be available for selection. For example, in a basic scenario with the dimensions unselected you can use only value conditions. For an explanation of how to use and combine conditions, see Condition types overview and Limitations on using baseline conditions.
Define an alert triggering threshold. For each condition you add, you need to choose a relational operator from a list and define a threshold value. Operators include:
- greater than
- less than
- greater than or equal to
- less than or equal to
- equal to (for value and cut-off conditions only)
Threshold values defined for alert-triggering conditions are not the same as the performance thresholds set in the server database for the purpose of generating performance reports.
- Threshold values defined for alert-triggering conditions are used only for the defined alerts and affect only one report: the Alert Log Viewer report.
- Performance thresholds set in the server database for the purpose of generating performance reports affect the appearance of, and values presented on, all of the performance reports.
Click Next to configure alert notifications. For more information, see Alert notifications.
What to do next
To define more detailed alert triggering rules, you can modify the default detector settings and configure a number of additional filters. For more information, see Configuring optional alert detector settings.