Thanks for the confirmation Martin, I was guessing this would be the behaviour
If pre processing rule is the only option to suppress inactive alerts , then the purpose of the maintenance mode itself is defeated here .
I completely understand the technical aspect behind that but in most of the cases devices are placed into maintenance by non administrative users like the Wintel team or the Unix team who do not have access to the IM console or do not have the needed knowledge to open nas and configure a rule in addition to setting the device in maintenance from UMP. In most of the cases a UIM admin needs to step in and create a pre-processing rule and this becomes quite a tedious task in a large scale environment where multiple changes are scheduled during the day.
In addition to the robot inactive alerts we do have a similar issue with alerts generated by net_connect probe for ping tests as they do not get suppressed when maintenance is set from UMP.
Wish there was a better way of dealing with maintenance