Firewall Rules Packet Simulator
A UTM Wizard or Tool that would run a Simulation of a defined Packet through the configured Firewall Rules.
The Wizard would require the following:
5) Protocol (ie. tcp or udp)
6) Interface that the packet reaches the UTM (Outside, Inside, DMZ)
The simulator will then test this packet against all the configured firewall rules, and report a final "Allowed" or "Denied", giving the reason for the Deny.
Bob Alfson commented
As Doug Foster pointed out in the UTM Community, this should include proxies and other things with hidden and automatic rules.