If (blocking) firewall-rule hit, trigger warning mail
I like to get warnings in case that one of my blocking rules was hit.
(for example, I like to monitor who sends packages to SMTP servers by himself, or may be by the SPAM Virus on his machine ;) )
Is there a way to set such trigger mails?
You better get ready for flooding your mailbox if you did such a thing. AFAIK there is no such option, sure something could be scripted up to watch the log and send you an email. If you sent your firewall logs to syslog then it could send you alerts on events you setup.