Radius irule

I assume you have a port wildcard (port = 0) listener to which this iRule is attached. You may get more mileage if you define four VSs, one for each port, all pointing to the same iRule (and pool). The VS matcher is faster than the iRule limiter, but it also allows you to more easily troubleshoot this case.

Either way, when you say it doesn't work for 1645, what is logged? You have a log statement for when the traffic is dropped, and one for when it is persisted. Which message is logged? Is the SERVER_DATA message being logged?