Exchange White Space
This is something that Exchange admins ask for. The trouble is that the number is buried in the event description.
SCOM has an event rule already that collects these events. The rule is called “Free space available in databases after online defragmentation.” and the event ID is 1221 with source “MSExchangeIS Public Store” from the application event log. You get a sentence in the event description like
“The database “XXXMSX02 SG1\XXXMSX02 SG1PF1″ has 63 megabytes of free space after online defragmentation has terminated.”
What I did was create an event view for that ID and the admin can just quickly go down the list for that day and look at the numbers in the description. People that know scripting may be able to do something funky to collect the information and alert on it depending on the size of the number. But I will leave that for someone else to do. 🙂 The Exchange admin was happy with the event view as it collated all the information in one place and made it easy to see the details.
It would be better if the Exchange dumped that into a performance counter or WMI so that it can be look at and alerts created.