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Create a MetricBase model trigger

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Create a MetricBase model trigger

Model triggers execute when the time-series data deviates from expected values.

Before you begin

Role required: admin

About this task

Probabilistic exponentially-weighted moving average (PEWMA) is the only model type supported. MetricBase uses this model to create a definition of expected, normal values.

Procedure

  1. Click MetricBase > MetricBase Triggers > Trigger Definitions and click New.
  2. Click Model Trigger - Detects and takes action when a metric value deviates from the trained model.
    The MetricBase Model Trigger form specifies the table and metric used to train the model.
    Model trigger
  3. On the form, fill in the fields.
    Field Description
    Name Name the model trigger.
    Model Trained model this trigger uses.
    Metric

    Automatically filled in based on the model.

    Table name

    Automatically filled in based on the model.

    Active Option to activate the trigger.
    Description Explanation of the trigger.
    Spike Direction Trigger execution criteria. Specify whether you want to trigger only on anomalies that occur above predicted values, only on anomalies that occur below predicted values, or both.
    Window Amount of data to use when calculating the moving, weighted average; the longer the window, the more data. The recommendation is 30 times the sampling interval. For example, if the time-series data is sampled every minute, make this value 30 minutes. Values must be multiples of the sampling interval.
    Active Turns on the trigger.
    Note: For the Window value, very short durations make the weighted average move with the data itself and fail to detect anomalies. Very long durations make the weighted average unresponsive to current trends in the data and may cause false triggers.
  4. Click Save.
  5. In the MetricBase Model Trigger Levels area, double-click each cell to add values that specify trigger parameters.
    Column Description
    Level Numbers that indicate increasing severity. For example, you might define level 1 to be 3 standard deviations from the mean. Level 2 might be 5 standard deviations. Each level should trigger a different Flow Designer flow. Level is often used in Conditional Scripts.
    Function Always Greater than or is, meaning that in order to trigger, the time-series metric must be greater than or equal to the number of standard deviations from the mean specified in Number of Standard Deviations.
    Number of Standard Deviation Float value specifying the number of standard deviations the time-series metric must be away from the mean to trigger an alert at this level.
  6. (Optional) Add additional rows in the table to create multi-layered triggering behavior.
    Each successive row should indicate a more severe condition.
  7. Click Update.
    The MetricBase Trigger Definitions page displays the list of defined triggers.
  8. Test your model and trigger on real data before deploying to production.
  9. (Optional) Add a triggering condition that determines whether or not a trigger executes a Flow Designer flow.
    For more information, see Create a triggering condition.

What to do next

Associate this trigger with a Flow Designer flow. For more information, see Assign a trigger to a flow.
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