Dear all, 3 Computers are linked together with cross over cable and computer B is the router. Computer A - Starlight Video Server(Solaris) - 192.168.0.11 Computer B - Iptables(Linux) - eth0 - 192.168.0.12 - eth1 - 158.192.92.102 Computer C - Video receiver(Windows) - 158.192.92.105 First # echo "1" > /proc/sys/net/ipv4/ip_forward it works fine, video receiver can receive the video from 192.168.0.11. The purpose for using iptables is that Internet use can get access our video server, also our video server can be protected by iptables. Second modprobe iptables for TABLE in filter nat mangle; do iptables -t $TABLE -F iptables -t $TABLE -X done; iptables -t nat -A PREROUTING -p udp --dport 1911 -i eth1 -j \ DAT --to 192.168.0.11: 1911 iptables -A FORWARD -p udp --dport 1911 -d 192.168.0.11 --j ACCEPT Video receiver can receive the video, but when we investigate the packets go into video receiver. Source IP: 192.168.0.11:1911 Destination IP: 158.192.92.105: 1069 Protocol: UDP Packet Len: 1.46KB Data Len: 1.42KB Third, we execute one more line in order to change the source IP # iptables -nat -A POSTROUTING -o eth1 -j \ SNAT --to 158.192.92.102 But the result doesn't change, we still get packet with source IP. 192.168.0 11. I'd be grateful for any helps or advices. Paul Yip
