Reverse SSH Tunnel

Solution 1:

There is no need to use nginx.

In your ssh daemon configuration (it should be /etc/ssh/sshd_config) set GatewayPorts to clientspecified and reload it. This is necessary for other systems to be able to connect to your tunnel. Without it, only programs running on your server will be able to use it.

Now all you need to do is modify your ssh command to listen on port 8888 instead of port 7777. This could look like

ssh -nNT -R '*:8888:localhost:5000' user@server

The asterisk tells sshd to listen to port 8888 on all interfaces, rather than just the loopback interface. This would fail if you haven't changed GatewayPorts.

Solution 2:

I second sciurus' answer but if for some reason you need to use nginx... my guess is that your upstream definition is broken.

The way you create your ssh reverse tunnel it only listens on localhost (127.0.0.1 and ::1), so you might want to try to give the following upstream definition a go:

upstream tunnel {
    server 127.0.0.1:7777;
}

Just for the record: I've never configured nginx my self yet so this is just a guess.