add "required datasource" capability
I am not quite sure how to express this in the UI, but there needs to be a way to indicate that for certain device types, a minimum set of datasources are required to be associated. We just had a case where the WinExchangeMBGeneral datasource (32 datapoints, some critical) just didn't get associated and we only found out after a major event. The active discovery stuff is very nice, but it is a "fail open" sort of thing where if AD does not successfully operate, you just have no way to know without heavy investigation. My idea is that once a device has been identified as a particular type (like Exchange server), there are a set of datasources that must be discovered and failure to do so is called out as an alert condition. At this point, you end up relying largely on luck to figure out whether this problem has happened.