Display the number of rules in a Azure Firewall Policy clearly
We know the limit is 10,000 rules per Firewall, however there does not seem to be a way to tell how many rules are actually in use.
Yes the Portal shows the number of rules in each rule collection and you could add those all up, but that isn't sensible.
Additionally, that is the number of rules that the customer has configured and according to Support, who checked with the Internal Team, not the true number of rules that count towards the limit.
Based on the documentation and Support discussion, the FW considers a rule as the unique tuple of source (IP), destination (IP/port), protocol.
So if you have a rule with a number of destinations, e.g. 5, then that would count as 5 rules toward the policy limit but only show as one in the Portal.
To add to the confusion slightly, IP Groups only count as one Source or Destination, regardless of the amount of IPs.