In order for MOM to detect and manage an application, a Management Pack often requires a computer group to be automatically populated with the names of the computers that have a particular application installed. In some cases, this computer group can be manually populated; however, in the interest of automating the process for operations personnel, a Management Pack author will almost always design computer groups to be automatically populated, based on the discovery of one or more computer attributes.
A computer attribute is a Management Pack object that is able to collect and store information gathered from managed computers. The attribute information is gathered from registry keys, values, or data.
The attributes that are collected are often a value, such as a product version number, or possibly a Boolean value that simply indicates whether an application exists on the managed node. For example, the Microsoft Windows Base Operating System Management Pack includes a computer attribute named "Microsoft Windows Current Version," which collects the version number of Windows. Another example is the Microsoft Windows DNS Server Management Pack, which includes a computer attribute named "Microsoft DNS Server" that checks to see if the DNS Server service exists on the managed node.
As mentioned previously, computer attributes can be used to enable a computer group to be automatically populated with the appropriate managed computers. To do this, these attributes will be referenced in a computer group formula, which is discussed in greater detail in the Computer Groups section of this document.