Although Systems Management Server (SMS) can automatically gather hardware and software information from clients, you might want to gather additional information that is not reported by default. You can customize what inventory is collected in the following ways:
Note If you modify an individual SMS_def.mof file on a client, SMS will overwrite it with the .mof file on the site server.
Use MOF Manager to Customize SMS_def.mof
About Custom Inventory
About the SMS_def.mof File
Managing Inventory Overview