ba36932d__Enterprise_Business_Community__Answer
[0] 8. [Question] WMI is capable of agentless operation to collect all Windows performance metrics. Why does Operations Manager need the SPI? [Answer] 
The virtualization SPI will not only collect performance metrics. Besides performance metrics, the agent will allow for service discovery of the VMware infrastructure. The agent will allow a more robust and comprehensive monitoring experience by allowing automatic actions as well as launch VMware specific tools to help diagnose problems.
Infrastructure Management Software Blog - HP Enterprise Business Community
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