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How to calculate license usage manually in UIM
In my experience there is no shortcut to this. The probes are categorized into service packs so in order to know 'what is left?' you need to know to which category that probe belongs and how much total you're entitled.
I recollect there used to be a document on old site which had a classification list of probes but unable to find it anymore
Yes, there is a quick way to find what is the count of individual probes deployed in environment.
Under <<Install_Dir>>\Nimsoft\bin---->Locate ProbeReport and start and from the reports TAB issue a probe 'Probe Statistics Report' you will have count of probes deployed under 'Count' column and all active probes under 'Active'(which is what you use) column.
I hope this helps.