Autonomous Anomaly Detector

StackState Self-hosted v4.6.x

This page describes StackState version 4.6.

Go to the documentation for the latest StackState release.

Overview

Anomaly detection identifies abnormal behavior in your fast-changing IT environment. This helps direct the attention of IT operators to the root cause of problems or can provide an early warning. The Autonomous Anomaly Detector (AAD) requires zero configuration. It is fully autonomous in selecting both the metric streams it will apply anomaly detection to, and the appropriate machine learning algorithms to use for each metric stream.

Note that a training period is required before the AAD can begin to report anomalies.

The anomaly detection process

The Autonomous Anomaly Detector (AAD) is enabled as soon as the AAD StackPack has been installed in StackState. When the AAD has been enabled, metric streams are identified and analyzed in search of any anomalous behavior based on their past. After the initial training period, detected anomalies will be reported in the following way:

  • The identified anomaly is given a severity (HIGH, MEDIUM or LOW).

  • The anomaly and time period during which anomalous behaviour was detected are shown on the associated metric stream chart. The color indicates the anomaly severity.

  • If the anomaly is considered to have a severity level of HIGH, an anomaly event is generated.

Anomaly severity

Each identified anomaly is given a severity. This can be HIGH, MEDIUM or LOW. The severity shows how far a metric point has deviated from the expected model and the length of time for which anomalous data has been observed.

Severity
Description

🟥 HIGH (red)

Reported only when data points with a low probability of occurrence are observed for at least 3 minutes. The least frequently reported severity. Generates an anomaly event.

🟧 MEDIUM (orange)

Reported for anomalous data observed for a short period of time or slightly anomalous data observed for a longer period of time. Reported less frequently than LOW severity and more frequently than HIGH severity anomalies. Useful for root cause analysis and can offer additional insight into HIGH severity anomalies reported on the stream.

🟨 LOW (yellow)

Reported when slightly anomalous data is observed. The most frequently reported anomaly severity. Less frequent occurrences of LOW severity anomalies indicates a higher reliability of anomaly reports from the AAD.

Anomaly events

When a HIGH severity anomaly is detected on a metric stream, a Metric Stream Anomaly event is generated. Anomaly events are listed on the Events Perspective and will also be reported as one of the Probable Causes for any associated problem. Clicking on the event will open the Event Details pane on the right-hand side of the screen.

  • Metric Stream - The name of the metric stream on which the anomaly was detected.

  • Severity - The anomaly severity. Anomaly events are only generated for HIGH severity anomalies.

  • Metric chart - A chart with an extract from the metric stream centered around the detected anomaly.

  • Anomaly interval - The time period during which anomalous behaviour was detected. This is also shaded on the metric chart.

  • Description - A description of the observed anomaly.

  • Elements - The name of the element (or elements) on which the metric stream is attached

Installation

Prerequisites

  • The AAD StackPack can only be installed within a Kubernetes setup. Please make sure that this is supported by your StackState installation.

  • It is also possible to install the AAD standalone within Kubernetes.

  • If you are not sure that you have a Kubernetes setup or would you like to know more, contact StackState support.

Install the AAD StackPack

To install the AAD StackPack, simply press the INSTALL button. No other actions need to be taken. A training period is required before AAD can begin to report anomalies.

Training period

The AAD will need to train on your data before it can begin reporting anomalies. With data collected in 1 minute buckets, the AAD requires a 2 hour training period. If historic data exists for relevant metric streams, this will also be used for training the AAD. In this case, the first results can be expected within an hour. Up to a day of data is used for training. After the initial training, the AAD will continuously refine its model and adapt to changes in the data.

Frequently Asked Questions

How are metric streams selected?

The AAD scales to large environments by autonomously prioritizing metric streams based on its knowledge of the 4T data model and user feedback. The metric stream selection algorithm ranks metric streams based on the criteria below:

  • The top ranking is given to metric streams with anomaly health checks.

  • Components in views that have the most stars by the most users are ranked highest.

  • From those components, the metric streams with the highest priorities are ranked highest. See how to set the priority for a stream.

  • Anomaly detection will be disabled on streams if more than 20% of their time is flagged as anomalous.

You cannot directly control the stream selected, but you can steer the metric stream selection of the AAD by manipulating the above-mentioned factors.

Know what the AAD is working on. The status UI of the AAD provides various metrics and indicators, including details of what the AAD is currently doing.

How fast are anomalies detected?

After an initial training period, the AAD ensures that prioritized metric streams are checked for anomalies in a timely fashion. Anomalies occurring in the highest prioritized metric streams are detected within about 5 minutes.

Can anomalies trigger alerts?

Yes. The AAD itself does not alert on anomalies found, but anomaly health checks can be added to components to automatically change the health status of the component to DEVIATING. This health state change event can then trigger notifications by adding an event handler to a view.

Uninstall

To uninstall the AAD StackPack, simply press the UNINSTALL button. No other actions need to be taken.

Release Notes

Autonomous Anomaly Detector StackPack v0.9.2 (02-04-2021)

  • Common version bumped from 2.4.3 to 3.0.0

  • StackState min version bumped to 4.3.0

See also

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