I copied the "Email me when a node goes down" alert, which is definitely working, and added a condition of 'Node category is equal to Network'.
All my network component have been assigned the Network category, but I'm only getting email alerts from the original out of the box alert, not the new one I created.
Is just 1 alert triggered as soon as it is matched? I'm thinking the out of the box alerts triggers and stops there.
Iain