PA Default Behaviour for un-matched UDP traffic?
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PA Default Behaviour for un-matched UDP traffic?

L2 Linker



I am pretty new to PA firewalls, and started looking at the default firewall behaviour for various kinds of traffic.

Hence wanted to know, what happens when PA sees unmatched UDP traffic, say a DNS reply, from outside for which it doesn't have a DNS request recorded from the inside? Does it drops the incoming DNS reply or does it allows it?


I have been searching internet for a while now, but couldn't get the correct answer to this question, any help appreciated :)





Correct, but PA will classify the traffic not as "unknown-udp" as an application. It will be a simple traffic drop. As traffic trying access from outside to inside without any session match. 

Alrighty, PA should document it somewhere those corner cases, as it becomes difficult for new bees, like me to understand the default PA behavior (or it can be just common sense, that I could be missing :) )


Thank you TraceforLife and Brad for quick responses and explanations.

Appreciate it!

here's some documentation :) Pro-Tips: Unknown Applications

Tom Piens
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