WMI filters can be used to define the scope of Group Policies based on computer attributes such as operating system, free hard disk space, brand and model, and so on. But to use them properly you should use them sparingly and test the performance of the filters before using them in your production environment since they can cause delays in Group Policy processing if you use too many of them or make them too generic in nature.
For example, try and avoid the “select * from” approach when making WMI filter queries and instead try to only include the objects from the WMI class you need to evaluate your filter query. Thus, instead of using something like this:
Select * From Win32_OperatingSystem where BuildNumber >= 7600 AND ProductType =’1′
use something like this instead:
Select BuildNumber, ProductType from Win32_OperatingSystem where BuildNumber >= 7600 AND ProductType =’1′
The above tip was previously published in an issue of WServerNews, a weekly newsletter from TechGenix that focuses on the administration, management and security of the Windows Server platform in particular and cloud solutions in general. Subscribe to WServerNews today by going to http://www.wservernews.com/subscribe.htm and join almost 100,000 other IT professionals around the world who read our newsletter!
Mitch Tulloch is an eleven-time recipient of the Microsoft Most Valuable Professional (MVP) award and a widely recognized expert on Windows Server and cloud computing technologies. Mitch is also Senior Editor of WServerNews. For more information about him see http://www.mtit.com.
