[Cialug] SSH Forwarding

[D. Joe Anderson]

On Thu, Jan 06, 2005 at 02:32:02PM +0000, timwilson011@mchsi.com wrote:
> I'm trying to forward ports to a remote machine at my work.  The problem is that
> I have to go to a gateway machine first.  I'm trying one of 2 different
> forwards, one VNC, and one X.  It doesn't matter which one I get working.
> 
> I'm trying to forward a local port to a remote machine running VNC.  My command was:
> ssh -g -L5985:172.18.128.54:5900 -P -t -C username@gateway
> 
> I used 5985 since I don't have a local VNC running on that port.  The remote
> machine is a Win2k box run tightvnc.  I then run vncviewer localhost:85.  It
> connects to the remote machine, I enter the password, but then the session dies.
>  If I turn on very very verbose, I get the following:
> debug1: channel_free: channel 2: direct-tcpip: listening port 5985 for
> 172.18.128.54 port 5900, connect from 127.0.0.1 port 42142, nchannels 3
> debug3: channel_free: status: The following connections are open:
>   #1 client-session (t4 r0 i0/0 o0/0 fd 5/6)
>   #2 direct-tcpip: listening port 5985 for 172.18.128.54 port 5900, connect from
> 127.0.0.1 port 42142 (t4 r2 i3/0 o3/0 fd 8/8)
> debug3: channel_close_fds: channel 2: r 8 w 8 e -1
> Any ideas?

Be sure that TightVNC allows connections on 5900 from localhost. 
I've seen clients (not sure which one at the moment, might be
able to tell you later when I next get onto the machines in
question) that disallow this by default, for some reason.  I've
had to change them such that, instead of disallowing that, that
that is the *only* thing they allow (ie, I don't want to allow a
non-tunneled connection from any other computer).

-- 
Joe