I had problems with some printers, sometimes, the print server just stops the queue and I only know when the user complains he can’t print ! This can cause several problems and so, I need to know when a printer stops. CUPS can warning you about that so you can do something about it.
Cups is able to send email notifications when some event occurs .
I’m using CUPS 1.3.7 with CentOS 5.10 x86