Hi
I am trying to forward UDP broadcast packets generated by embedded devices on a subnet 192.168.6.0/24 as NATted unicast packets to a another subnet 192.168.1.0/24 .
The broadcast packets arrive at RB2011 router port 1 as 192.168.6.255 udp port 12600 (dst mac FF:FF..FF:FF).
The DST-NATed packets leave at RB2011 router port 10 as 192.168.1.100 udp port 13601 , as per the NAT rule I created.
If I bridge the two ports and enable the bridge IP firewall , I have success . This proves my correct implementation of the IP NAT rule , port IP address settings etc.
However , if I disable the bridge , and rely on forwarding via the default routes , it fails . It still NATs , but does not forward to port 10.
A twist in the tale is, if I replace the broadcast transmission with a unicast transmission to port 1 router address 192.168.6.1, the NAT ( altered to unicast type) and forwarding works perfectly.
I have thus inferred that the router forwarding machinery gets somehow nervous about the fact that the original raw input was of broadcast type.
But should the route forwarding process not be abstracted by the fact that the packet has been correctly NATed ? or lies the answer in the fact that the original MAC dst address is a broadcast address and gets somehow rejected by the forwarding process? Ok, I am running in circles.
Oh , I am a rookie , my first post , an absolute beginner.
Any help why the routing process fails.
Thanking in anticipation.