Hello.
I have RouterOS 5.24 and NAT rules like this:
RT and KT is names of internet providers (yes, i have 2 wans)
;;; S2 KT
chain=dstnat action=dst-nat to-addresses=192.168.xxx.yyy
connection-mark=S2_conn_KT
;;; S2 RT
chain=dstnat action=dst-nat to-addresses=192.168.xx.yyy
connection-mark=S2_conn_RT
Mangle rules:
;;; S2 KT
chain=prerouting action=mark-connection new-connection-mark=S2_conn_KT passthrough=yes protocol=udp in-interface=WAN_KT dst-port=27015-27022
;;; S2 RT
chain=prerouting action=mark-connection new-connection-mark=S2_conn_RT passthrough=yes protocol=udp in-interface=WAN_RT dst-port=27015-27022
Then i want NAT some packets from this “flow” to another port. I have a small ports range and map it, see the screenshot.
First two JUMP rules:
;;; A2S_INFO → Proxy
chain=dstnat action=jump jump-target=fucking_mapping protocol=udp in-interface=!default-bridge content=TSource Engine Query
;;; InetSearch → Proxy
chain=dstnat action=jump jump-target=fucking_mapping protocol=udp in-interface=!default-bridge content=InetSearchServerDetails
And all works fine! BUT! When client (197.12.43.61, 57000) send packet “\xFF\xFF\xFF\xFFTSource Engine Query” and after got response from my proxy-server on 279xx (e.g. 27915) to which i NAT this packet, he send from same ip:port another packet, like this: “\xFF\xFF\xFF\xFFU\xFF\xFF\xFF\xFF” and this NATed to 279xx TOO!
I catch this packet by my application (proxy-server) on local machine behind NAT. I want NAT only needed packets. What i doing wrong?
Please, help me to solve this stupid situation.