Remote Display Setup - Knoppix

[johnj123]

was able to use ssh -x to call up a xterm from one server to the other. This is not correcting the problem that I'm having.

1) From a RHEL 5.0 server (192.168.222.51) I set the following:
export DISPLAY 192.168.222.50:0.0
2) Execute "xterm" and I get the following error:
xterm Xt error: Can't open display: 192.168.222.50:0.0
3) On the 192.168.222.50 server running Knoppix, I set the following:
xhost + <Enter>
access control disabled, clients can connect from any host
4) Execute "xterm" again from the RHEL server (192.168.222.51) and get the following error:
xterm Xt error: Can't open display: 192.168.222.50:0.0

It seems that I've got some type of firewall or something on the Knoppix system thats stopping these remote displays? Once again ssh is working between the two servers and I'm able to remote a display "xterm window" from the Knoppix server to the RedHat server.

I can't find how this was setup on Knoppix and this problem is also stopping me from not just remoting displays but using telnet.

Thanks,
John

[Capricorny]

was able to use ssh -x to call up a xterm from one server to the other. This is not correcting the problem that I'm having.
It seems that I've got some type of firewall or something on the Knoppix system thats stopping these remote displays? Once again ssh is working between the two servers and I'm able to remote a display "xterm window" from the Knoppix server to the RedHat server.

X is default set up under Debian not to listen to TCP. I'm not sure, but maybe the problem is there.
I modified /etc/X11/xinit/xserverrc to just say

X -noreset -br

and changed /etc/init.d/knoppix-startx in a similar way, omitting the

-nolisten tcp

option from the startx line. After that,

ssh -X -l <username> <servername>

works for me. (From Mandriva, the -X switch in ssh is not necessary.)

I did not have to do ANY xhost+ 'ing or DISPLAY= 'ing to get it to work. (Strange? Dunno.)

[Capricorny]

X is default set up under Debian not to listen to TCP. I'm not sure, but maybe the problem is there.
I modified /etc/X11/xinit/xserverrc to just say

X -noreset -br

and changed /etc/init.d/knoppix-startx in a similar way, omitting the

-nolisten tcp

option from the startx line. After that,

ssh -X -l <username> <servername>

works for me. (From Mandriva, the -X switch in ssh is not necessary.)
I did not have to do ANY xhost+ 'ing or DISPLAY= 'ing to get it to work. (Strange? Dunno.)

While this is correct, and probably is relevant under some conditions, it is by no means necessary to run ssh and open X displays - I know now!

ssh -X -l <username> <servername>

is enough, at least with a Tru64-Unix server. I'll try it out more and report on what I find. Beware that the local Xserver (on your machine) must have the necessary resources to display what the 'client' sends to it. For this reason, I could not start tru64 Emacs remote - some X fonts are missing locally.

Using ssh to run programs on other machines is a great way to avoid installing all kinds of exotic software on the Knoppix box, with the consequential need for extra infrastructure...