Static Threshold Unit Monitors in Operations Manager 2007

In Operations Manager 2007, static threshold unit monitors measure a performance counter object relative to a user-defined static value, at specific intervals. When the value of the performance object being measured exceeds the defined threshold, the state of the monitor changes.

You can use the Create a Unit Monitor Wizard to create a static unit threshold monitor. You can open the wizard by clicking Create a monitor in the Actions pane of the Authoring area and then selecting Windows Performance Counter under Select the type of monitor to create.

In Operations Manager 2007, two types of static thresholds are available:

  • Single threshold
  • Double threshold

Single Threshold Monitor

A single threshold monitor has one limit. When the performance counter goes either above or below that limit, the state of the monitor changes. The state change can be configured to be success, warning, or error.

An example of what a single threshold monitor does is that it monitors remaining free disk space. For example, suppose you want to monitor free disk space. Using a single threshold monitor, you might set a threshold of 1 GB so that when your free disk space falls below 1 GB, a warning or error state is set.

Operations Manager 2007 the following types of theshold unit monitors:

  • Simple threshold   A simple threshold monitor measures the value of a performance object against a fixed limit. If the value of the performance object goes above or below the fixed limit, the state of the monitor changes. On one side of the threshold, the state of the monitor is success; on the other side, the state is either warning or error.
  • Average threshold   An average threshold monitor measures the value of a performance object against a fixed limit. In addition, an average threshold monitor examines n number of samples and takes the average value of those samples to determine whether the threshold has been exceeded. This type of threshold monitor always examines the most recent n number of samples.
  • Consecutive samples over threshold   The consecutive-samples-over-threshold monitor is useful when sudden increases in a performance counter generate false alarms. A consecutive-samples-over-threshold monitor changes the state of the monitor only if the performance counter exceeds a threshold for n number of consecutive samples. With this type of monitor, you can configure the threshold to be greater than, greater than or equal to, less than, or less than or equal to a specified value.
  • Delta threshold   A delta threshold monitor measures the rate of change in n number of samples. The rate of change can be expressed as an absolute value (for example, a change of 10 GB over the last five samples) or as a percentage (for example, a change of 5 percent over the last five samples).

Double Threshold Monitor

A double threshold monitor examines two limits. When a performance counter value crosses the first limit, the state of the monitor changes. If the value continues to climb or decline and crosses the second limit, the state changes a second time.

For example, assume the first threshold is set at 1.5 GB and the second one is set at 1 GB. If the amount of free disk space is above 1.5 GB, the state of the monitor is success (green). If free disk space goes below 1.5 GB, the state of the monitor changes to warning (yellow); if free disk space goes below 1 GB, the state changes to error (red).

See Also

Tasks

How to Create a Self-Tuning Monitor in Operations Manager 2007
How to Create a Static Threshold Monitor in Operations Manager 2007
How to View a Performance Baseline in Operations Manager 2007

Concepts

Management Pack Objects in Operations Manager 2007
Operations Manager 2007 Create a unit monitor Wizard

Other Resources

About the Authoring Pane in Operations Manager 2007

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