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Old 01-30-2010, 10:27 PM
fd15k fd15k is offline
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If you're trying to monitor latency and/or reachability to more than 1 box behind the NAT, then I think your best option is to use some "hacking". Setup UDP port forwarding, say ports 1025 and 1026 (completely arbitrary ports) to boxes A and B, and send a UDP datagram to either of those ports with payload "Hello, world!" Because you got no service listening to those datagrams on boxes either box, those boxes will respond with ICMP unreach (destination port unreachable). So instead of having ICMP echo request -> echo reply, you will have UDP dg -> ICMP unreach
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