Well...I do lurk around in forums - old habits die hard... As for CHX-I, I am somewhat surprised it is still being used after all these years....
If I remember correctly - the rule had the ff-ff-ff-ff as a destination. I suggested changing that to Any to avoid this particular shortcoming....
It is probably the DHCP NACK/ACK during renewal/ rebind. CHX-I ignores this particular instance - a DHCP force allow incoming (UDP rule) would...
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