problem with remote accessing c/w firewall

nonidentity · 04-16-2009, 04:14 PM

I want to access a PC with ubuntu that is remote. I can log into the PC when I am there - my son can do this for me.
It is behind a firewall and has a 10,x,x,x address. I can invoke a session from there outwards and browse BUT I cannot access the PC remotely from where I am now.
Obviously if there was Logmein 4 linux then I could get around this as port 80 is OK.
I cannot ssh or vnc it - any ideas?

derek990 · 04-16-2009, 04:57 PM

The remote PC you are trying to access is blocked by a firewall. If you have access to the firewall/router you should forward the SSH(22) and VNC(5900) port to your Ubuntu machine. Before implementing this you have to set a static ip address on the Ubuntu machine.

nonidentity · 04-16-2009, 05:02 PM

Unfortunately I cannot access the f/wall

perhaps I can tunnel with openvpn?

derek990 · 04-17-2009, 12:28 AM

Openvpn would work except you would have to initiate the tunnel from the (source) Ubuntu machine in order to keep that port(s) open in the firewall. However this tunnel would have to be pointed to a machine on a static ip which you could then open a VNC connection through the tunnel. If you are using dynamic ip's at the destination of the openvpn tunnel, you would most likely like to have some type of dynamic dns software which would allow your ubuntu machine to establish a tunnel with you anywhere you are. Maybe i have made this sound more complicated than it really is but it does work. The key is to keep the tunnel connected to whatever machine you are using so you can launch a VNC session.

nonidentity · 05-02-2009, 02:36 PM

Maybe I was not very clear.

So I am at home with ADSL connection. I have full control of my environment.

My son, is studying and his PC is behind a "corporate" firewall. His address is a 10,x,x,x range and seems static.

He can initiate a PuTTY session from his position and connect via DynDNS to my PC.

However the objective is that I need to connect to his PC and conduct some changes.

In Win I would use LogMeIn as a service and in fact I do so with his laptop; however this is Ubuntu on both ends thus PuTTY or VNC from either end cannot connect.

How do I over come this?

allend · 05-02-2009, 08:20 PM

What you want is a reverse ssh tunnel. Google for 'reverse ssh' and you will find many good how-tos.