Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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Yes, this is correct, but remember about FORWARD chain (you must allow for this traffic there if you have DROP policy on it), and of course you must have SNAT rule in order to make any usefull efect. something like this;
iptables -A POSTROUTING -t nat -o eth0 -j SNAT --to-source 126.96.36.199 -s 192.168.1.202
Of course you have 188.8.131.52 ip addres on eth0, right?
This rules should work. Hmm... Try to iptables -L -t nat -v to look if any packets coming in this dnat chain. Try to use tcpdump on your LAN card (eth1?), to watch if any packets to telnet service on that lan host coming. something like;
tcpump -i eth1 port 23 and host 192.168.1.202 -n
And watching on tcpdump try to login on telnet (from any remote machine out of your network). Tell us if any packets going out through your router to that telnet machine (tcpudmp show it to you).
You may need to try it, get someone to initiate a telnet session while looking at tcpdump to see what's happening, and what port is actually being used, (because what you have looks ok to me, but wouldn't know for sure unless tested).
You might also need tell the client to specify port 23
Seeing as how i was LOST. I opted to strip out any garbage and start from scratch.
My Firewall is set to simple NAT outbound connections to share the internet.
All default chains are set to allow.
So NOW I want to just forward inbound ( from the internet ) telnet ( port 23) connections to the WAN ip of 184.108.40.206 (eth0) through 192.168.1.1 (eth1) to to host server 192.168.1.202 on port 23.
Please advise accordingly.
Thanks a lot.
It looks like packets to telnet machine going out from router (2 pkts). The question is; is 192.168.1.203 answering fot this packets? Is there a telnet service? check it by running tcpdump with option; tcpdump -i eth1 host 192.168.1.203 and port 23 -n
And watch if telnet machine answering for syn packet (try to login from "somewhere in world" to telnet, and in this time look on tcpdump screen)
If you can, show here some log of this tcpdump session.
I can telnet on port 23 to the internal machine from my firewall so I know that much works. As well as a ton of other hosts. Its an application server and everyone telnets into it. Could you suggest some rules again; just the simplest port forward rule, minimal stuff needed to get the port forwarded.