X-Forwarding freezes keyboard on ThinClient Vortex86

[Jordi Sanfeliu]

Hello all,

Please send a Cc: to me in addition to the list. I am not subscribed and this 
will make it easier for me to follow the thread and reply. Thanks.

My scenary is as follows:

I have a Linux server with OpenSSH 3.7.1p2 installed and this server acting as 
an LTSP. Some PCs (all Pentium+ classes) acting as X-Terminals connects to this 
server via PXE boot --> DHCP --> booting LTSP-kernel (2.4.24) --> executing 
XFree86 4.3.99 --> and finally executing "ssh -X user at linuxserver some_program" 
(same version OpenSSH as server) in order to execute the OpenOffice binary and 
nothing more.

Thanks to the X-Forwarding feature, all the OpenOffice executes in a very 
capable Linux server for all PCs acting as a X-Terminals and the things works 
fine in an environment very stable and secure.

Now the BIG problem
-------------------
Recently I'm testing a new Thin Client solution (http://www.vortex86.com) to 
subsitute these PCs for something more "thin" and little. This Thin Client have 
a Vortex86 processor at 200Mhz and 128MB of RAM, and is a good solution in order 
to think to convert all the PCs into this very little Thin Client.

To test this new Thin Client almost nothing was changed in the LTSP 
configuration, just the MAC address and the video configuration and resolution. 
The problem arises when unexpectedly the X-Forwarding feature hang the keyboard 
after 3 or 4 key-clicks. The mouse continues working (well at least it moves), 
but the keyboard does not respond, keyboard-leds are dead and the display freezed.

If I remove the line "ssh -X user at linuxserver ....." and (manually) executes 
from the Linux server the OpenOffice program with the DISPLAY variable 
containing the Thin Client IP address (that is not using X-Forwarding nor 
OpenSSH at all), it works fine!!!.

Moreover, if I executes from the Thin Client "X -query" in order to begin an XDM 
session (or KDM session), it works fine!!!

That's mean that the problem is on X-Forwarding. But what is the cause for this 
strange behavior?

Thanks in advance.

-- 
Jordi Sanfeliu
FIBRANET Network Services Provider
http://www.fibranet.com