Re: Problems with ssh and tunnelling with cygwin 1.5.12

[Nick Wisniewski <nw at physics dot ucla dot edu>]

Igor Pechtchanski wrote:
> On Fri, 12 Nov 2004, Nicholas Wisniewski wrote:
>
> > Hello,
> >    I'm trying ssh and tunnel to various machines.  I can ssh just fine
> > without tunnelling (i.e. ssh user@machine.net).  When I try to tell ssh
> > to tunnel (ssh -X user@machine.net), it prompts me for my password, and
> > then hangs.
>
>
> This is an X-related issue, and as such should go to the cygwin-xfree
> list.  I'm redirecting my reply there -- please remove <cygwin at cygwin
> dot com> from further discussion.

I'm using Exceed as an X-windows client, not Xorg, so I don't think it 
is.  In any case, I thought that all ssh cared about was whether there 
was a DISPLAY set or not.


> >     When I look at the task manager, I see that sh.exe is taking up all of 
>
> ^^^^^^
>
> >     the available CPU. If I kill sh.exe from the task manager, ssh 
>
> ^^^^^^
>
> >     continues fine and I am connected and tunnelling. 
>
>
> Is this really sh.exe?  Can you check whether this sh.exe process is
> running before you start ssh (e.g., compare the outputs of "ps -ef" before
> and after "ssh -X")?
before
bash-2.05b$ ps -ef
     UID     PID    PPID TTY     STIME COMMAND
    Nick    2888       1 con  13:34:32 /usr/bin/bash
    Nick    4052       1 con  13:37:33 /usr/bin/bash
    Nick     236    4052 con  13:39:22 /usr/bin/ps

after
bash-2.05b$ ps -ef
     UID     PID    PPID TTY     STIME COMMAND
    Nick    2888       1 con  13:34:32 /usr/bin/bash
    Nick    4052       1 con  13:37:33 /usr/bin/bash
    Nick    3936    2888 con  13:40:16 /usr/bin/ssh
    Nick    4012    3936 con  13:40:25 /usr/bin/sh
    Nick     936    4052 con  13:40:29 /usr/bin/ps


> I don't recall any option that would make ssh start a shell on the local
> machine.  Are your ssh config files customized?  Are you running keychain,
> or autossh, or any other ssh-related scripts?

I just uninstalled everything.  I reinstalled nothing but the default 
packages and open-ssh.  I'm running /usr/bin/ssh out of the box with no 
modifications.  As you can see from the ps, sh is being started by ssh.

As I mentioned before, if I kill sh.exe from the task manager, 
everything works fine (i.e. it finishes logging in and I can display 
things from the remote machine).


> Are you running Cygwin's ssh?  Are you running /usr/bin/ssh, or is ssh
> aliased to anything?  Is your DISPLAY set when you run ssh.exe?  Have you
> tried trusted X forwarding ("ssh -Y")?

I'm running /usr/bin/ssh. ssh -Y has the same symptoms as ssh -X

bash-2.05b$ echo $DISPLAY
localhost:0.0



> >    I'm running XP pro, service pack 2.  I've turned off the XP firewall and
> > Sophos virus programs and still get the same behaviour.  The same behavir
> > happens on this machine with cygwin 1.5.11 as well.
> >
> >
> >     Has anybody ever seen this before? 
>
>
> This doesn't sound like anything that's been reported before.
> 	Igor

Nick



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