I am struggling to figure out why I cannot display GUI applications from one of the Sun Solaris 10 servers (named espresso) on the network over to my local Linux workstation (beluga). Seems to work perfectly fine when I use my other Solaris 8 (stoli) box for display.


Here is what I do, the part that works fine:

stoli: xhost+
stoli: rlogin espresso
espresso: setenv DISPLAY stoli:0.0
espresso: oclock

Now trying the same thing over to linux box, beluga, and it fails with message "Error: Can't open display: beluga:0.0":

beluga: xhost+
beluga: rlogin espresso
espresso: setenv DISPLAY beluga:0.0
espresso: oclock

Same problem and same error message when I try to run oclock on a Linux server to my Linux workstation. Yet it works fine when displaying from Linux server to Solaris workstation.

Both workstations sit on a local network behind the firewall, so the software firewall on both is disabled.

I tried a workaround with "ssh -X (or -Y) espresso /usr/bin/oclock". That works, but when I replace the oclock with the actual application that I need to run, in half the instances it works, and in half the application crashes after showing the splash screen. Same behavior if I "ssh -X espresso" into a terminal shell and then running the application from there.

Any ideas of what could be missing in this puzzle?

Are you root user on both?

Yes, I have root access.

Never mind though, I just figured what was going on. Just in case if anyone else has this problem:

For Ubuntu and Gnome change the line "DisallowTCP=true" to "DisallowTCP=false" in /etc/gdm/gdm.conf or use gdmconfig to deactivate the setting "Always disallow TCP connections" for the X server.


More detail:

http://www.xskat.de/xskat-lan-irc.html

a) Configure the X servers to listen for connections on port 6000.
The X server has to be started without the option "-nolisten tcp". Sadly this has to be done quite differently depending on OS and display manager.

For SUSE and KDE set DISPLAYMANAGER_XSERVER_TCP_PORT_6000_OPEN to "yes" as root using the /etc/sysconfig editor in yast2 under "Desktop -> Display manager" and execute SuSEconfig afterwards. You may have to comment the line "ServerArgsLocal=-nolisten tcp" in /etc/opt/kde3/share/config/kdm/kdmrc with a "#" at the beginning of this line. Also, there should be no option "-nolisten tcp" in /etc/X11/xdm/Xservers.

For Ubuntu and Gnome change the line "DisallowTCP=true" to "DisallowTCP=false" in /etc/gdm/gdm.conf or use gdmconfig to deactivate the setting "Always disallow TCP connections" for the X server.

Logout and restart the graphical user interface then. If executing the command "netstat -an|grep :6000" gives some output, the X server is listening on port 6000.

b) Disable firewall for port 6000.
If a firewall is protecting against other LAN hosts, at least port 6000 has to be opened.

Don't open ports for connections from the internet!

thanks - your tip on the start xserver with nolisten tcp helped.
i edited the cfg file but failed to restrt the xserver. once i restarted my remote display worked.