Gtk-WARNING **: cannot open display: (FC3)

ajkrishock · 08-26-2006, 11:45 AM

Hello

I am having some issues opening and displaying programs on my PC from my server. I'll first describe my network.

I have three computers on my network. They are:

"Tony" - This is my PC. Dual boot XP and Fedora core 3. Cabled to the router
"Tina" - My Wife's XP machine. Wirelessly connected
"Server" - My web/ftp/backup server running Fedora core 3. Cabled to the router.

I use the X-Win32 application from the XP machines to open xterm's and run linux applications on the XP desktops. No problems there. I also have several directories on the server shared via Samba.. no problems there either.

The hosts file on the server and "tony" machines is identical, and it looks like:

# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
192.168.2.1 router
192.168.2.3 server
192.168.2.4 tony
192.168.2.5 tina

Problem comes in when, from "Tony", I boot into FC3 and then try to open apps on the server and display them on "Tony". I can ssh into the server from "tony" without problems:

[tony@tony ~]$ ssh -l tony server
tony@server's password:
Last login: Sat Aug 26 11:32:12 2006 from tony
[tony@server ~]$

Now, if I try to run applications, I get:

[tony@server ~]$ xclock &
[1] 25253
[tony@server ~]$ Error: Can't open display:

Now for the weird part. If I do an "echo $DISPLAY" on the server, I get:

[tony@server ~]$ echo $DISPLAY

[tony@server ~]$

I get nothing. A blank line. That's it.

If I do an "echo $DISPLAY" on "tony", I get:

[tony@tony ~]$ echo $DISPLAY
:0.0
[tony@tony ~]$

So what the heck is going on here?

b0uncer · 08-27-2006, 04:14 AM

First make sure that both the server and your ssh client configurations allow X11 forwarding. Then, if it still does not work, you could try to

Code:

xhost +yourserver

to allow it to have connections to your X. About this latter one, I'm not completely sure if it helps, since I've used it myself like "xhost +localhost" to get around a problem where I couldn't run su-started programs from the console since the X server denied the connection as root was not allowed to connect to the display I was running.

Anyway first check out the X11 forwarding. Both server and client. Try even running

Code:

ssh -X servername

or

Code:

ssh -Y servername

(for trusted forwarding). I found out last year that though my settings were ok, I was unable to forward X11 connections from a server if I didn't start the ssh connections with the -X switch.