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I want to access my Linux server(vnc) from a distant machine which has most ports blocked with the exception of 21, 25, 80, 135, and 445.

So, I would like to know if theres a way to communicate with my vnc server on the server, while using an available port on client.

i.e. port 25

So I think essentially I need the serverside router to forward packets coming in on port 25 to linux server machine(servername, p5900), which should forward them on to itself on port 5900.

And when transmitting, I need the server OR to router to send out packets changing their port to 25.

Im totally lost on how to acheive this. Please help(much appreciated). Thanks

I do not use smtp.

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What VNC server and client are you using? – Wesley Apr 19 '10 at 23:36
Discuss the problem with your system administrator. – John Gardeniers Apr 19 '10 at 23:40
Oooo... good point John. facepalm – Wesley Apr 20 '10 at 3:24

I think you just answered your own question. You'll have to edit your VNC client to send traffic out over the alternate port. Then go into the firewall/router that the VNC server is behind and port forward your alternate port to the VNC server. Then edit your VNC server to send responses back over the alternate port or edit the VNC server's router/firewall to re-map outbound VNC traffic to the alternate port. I suppose you could get really fancy and see if the firewall supported changing only a certain stream's port mapping, but that could get complex.

We'd need to know what VNC server and client your using if you want more specific help on how to edit those settings, but I'm sure you could find that info just as easily somewhere on the intertubes.

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Just make your VNC server listen on port 25. Then have your firewall forward all connections to port 25 to your server's IP. Then use the vnc client to connect to "your-external-ip:25".

Refer to your VNC client's documentation on how to connect to specific server ports.

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