Applies To: System Center Operations Manager 2007
This topic has been updated in the latest version of the System Center Management Pack Authoring Guide on the TechNet Wiki.
Aggregate monitors group multiple monitors to provide a single health aggregated health state. This provides an organization to all of the monitors targeted at a particular class and provides a consolidated health state for specific categories of operation.
Standard Aggregate Monitors
Every class has four standard aggregate monitors: Availability, Configuration, Performance, and Security. These are in the System.Health.Library management pack and targeted at the Entity class. Because all classes inherit from the Entity class, all classes inherit these standard monitors. The standard set of aggregate monitors will be sufficient for most classes.
Most monitors will fall into one of the four categories represented by the standard aggregate monitors. Because of this, custom aggregate monitors will typically use one of the standard aggregate monitors as their parent instead of being positioned alongside them directly under the entity health. Unit monitors and dependency monitors will similarly use either a custom aggregate monitor or one of the standard aggregate monitors as their parent.
Standard aggregate monitors
Custom Aggregate Monitors
Management packs can include custom aggregate monitors specific to the requirements of classes in a particular application. These monitors may use another aggregate monitor for their parent or the top level Entity State similar to the standard aggregate monitors use. Custom aggregate monitors can be configured underneath another aggregate monitor or attached directly to the entity state.
For example, the Windows Server 2008 Operating System (Monitoring) management pack includes an aggregate monitor called Microsoft.Windows.Server.2008.OperatingSystem.CoreServicesRollup that is used to combine the health of the different services that are monitored by this management pack. There are nine services that the management pack considers critical to the operation of a computer running Windows Server 2008. Instead of positioning these directly under the Availability aggregate monitor alongside other unit monitors, the aggregate monitor provides a combined health measurement for all the related services.
This aggregate monitor is illustrated in the following diagram.
Core Windows Services Rollup aggregate monitor
Health Rollup Policy
Each aggregate monitor must define a health rollup policy which is the logic that is used to determine the health of the aggregate monitor based on the health of the monitors under it. The possible health rollup policies for an aggregate monitor are as follows:
The state of the aggregate monitor matches the state of the child monitor with the worst health state. This is the most common policy used by aggregate monitors.
Worst state health policy
The state of the aggregate monitor matches the state of the child monitor with the best health state.
Best state health policy