[CentOS] Remote X connection to CentOS 5.5 using Xming -ac

Tue Jun 15 19:10:02 UTC 2010
Alexander Farber <alexander.farber at gmail.com>

Hello,

I've rented a dedicated root server (SR7 at strato.de)
and would like to run qemu at it, but get the error:

 # qemu -hda install.img -cdrom install47.iso -boot d
 Could not initialize SDL - exiting

It seems that I have to establish X connection,
so I've installed Xming at my WinXP laptop
and at the server I have changed these 3 lines
in the /etc/ssh/sshd_config:

  X11Forwarding yes
  X11DisplayOffset 10
  X11UseLocalhost yes

And also I have installed these Xorg packages:

  # rpm -qa | grep -i xorg
  xorg-x11-utils-7.1-2.fc6
  xorg-x11-drv-evdev-1.0.0.5-5.el5
  xorg-x11-drv-vesa-1.3.0-8.2.el5
  xorg-x11-filesystem-7.1-2.fc6
  xorg-x11-font-utils-7.1-2
  xorg-x11-server-utils-7.1-4.fc6
  xorg-x11-xkb-utils-1.0.2-2.1
  xorg-x11-xfs-1.0.2-4
  xorg-x11-fonts-base-7.1-2.1.el5
  xorg-x11-drv-keyboard-1.1.0-3
  xorg-x11-server-Xorg-1.1.1-48.76.el5_5.1
  xorg-x11-drv-mouse-1.1.1-1.1
  xorg-x11-drv-void-1.1.0-3.1

Then I've restarted the server and run PuTTY
to connect to it, where I have checked the
Connection->SSH->X11->Enable X11 forwarding

(Sorry for mentioning all this Windows stuff,
but I don't have a Unix desktop and also the
problem seems to be in the CentOS config)

When I connect to the CentOS machine,
the DISPLAY variable isn't set at all.
Shouldn't SSH set it to localhost:10.0 ?

I try to set DISPLAY manually to localhost:10.0
and my_ip_address:0.0 and I have tried
connecting as root and as a non-root user.

Still I can't run any X programs like xterm:

$ echo $DISPLAY

$ xterm
xterm Xt error: Can't open display:
xterm:  DISPLAY is not set

$ export DISPLAY=localhost:10.0
$ xterm
xterm Xt error: Can't open display: localhost:10.0

$ netstat -an |grep ESTABLISHED (my sshd listens at port 443)
tcp        0     52 ::ffff:85.214.XXX.XXX:443
::ffff:88.153.153.102:2646  ESTABLISHED
tcp        0      0 ::ffff:85.214.XXX.XXX:443
::ffff:88.153.153.102:2566  ESTABLISHED

$ export DISPLAY=88.153.153.102:0.0
$ xterm
xterm Xt error: Can't open display: 88.153.153.102:0.0 (after long time)

And the firewall is off:

$ sudo /sbin/service iptables status
Firewall is stopped.

And I don't see anything in the Xming log (pasted below).

Does anybody please have a hint for me?
My Linux knowledge is a bit rusty :-)

Should I start X somehow at the Linux side?
(I've checked chkconfig --list, found nothing there)

Regards
Alex

PS: Xming log below:


Welcome to the Xming X Server
Vendor: Colin Harrison
Release: 6.9.0.31
FreeType2: 2.3.4
Contact: http://sourceforge.net/forum/?group_id=156984

C:\Program Files\Xming\Xming.exe :0 -ac -clipboard -multiwindow

XdmcpRegisterConnection: newAddress 10.216.41.31
winAdjustVideoModeShadowGDI - Using Windows display depth of 32 bits per pixel
winAllocateFBShadowGDI - Creating DIB with width: 1920 height: 1200 depth: 32
winInitVisualsShadowGDI - Masks 00ff0000 0000ff00 000000ff BPRGB 8 d 24 bpp 32
glWinInitVisuals:1596: glWinInitVisuals
glWinInitVisualConfigs:1503: glWinInitVisualConfigs
glWinSetVisualConfigs:1581: glWinSetVisualConfigs
init_visuals:1055: init_visuals
null screen fn ReparentWindow
null screen fn RestackWindow
InitQueue - Calling pthread_mutex_init
InitQueue - pthread_mutex_init returned
InitQueue - Calling pthread_cond_init
InitQueue - pthread_cond_init returned
winInitMultiWindowWM - Hello
winInitMultiWindowWM - Calling pthread_mutex_lock ()
winMultiWindowXMsgProc - Hello
winMultiWindowXMsgProc - Calling pthread_mutex_lock ()
glWinScreenProbe:1390: glWinScreenProbe
fixup_visuals:1303: fixup_visuals
init_screen_visuals:1336: init_screen_visuals
(--) 5 mouse buttons found
(--) Setting autorepeat to delay=500, rate=31
(--) winConfigKeyboard - Layout: "00000407" (00000407)
(--) Using preset keyboard for "German (Germany)" (407), type "4"
Could not init font path element C:\Program Files\Xming/fonts/misc/,
removing from list!
Could not init font path element C:\Program Files\Xming/fonts/TTF/,
removing from list!
Could not init font path element C:\Program Files\Xming/fonts/Type1/,
removing from list!
Could not init font path element C:\Program Files\Xming/fonts/75dpi/,
removing from list!
Could not init font path element C:\Program Files\Xming/fonts/100dpi/,
removing from list!
Could not init font path element C:\Program Files\Xming\fonts\dejavu,
removing from list!
Could not init font path element C:\Program
Files\Xming\fonts\cyrillic, removing from list!
Could not init font path element C:\WINDOWS\Fonts, removing from list!
winInitMultiWindowWM - pthread_mutex_lock () returned.
winInitMultiWindowWM - pthread_mutex_unlock () returned.
winInitMultiWindowWM - DISPLAY=127.0.0.1:0.0
winMultiWindowXMsgProc - pthread_mutex_lock () returned.
winMultiWindowXMsgProc - pthread_mutex_unlock () returned.
winMultiWindowXMsgProc - DISPLAY=127.0.0.1:0.0
winProcEstablishConnection - Hello
winInitClipboard ()
winProcEstablishConnection - winInitClipboard returned.
winMultiWindowXMsgProc - XOpenDisplay () returned and successfully
opened the display.
winInitMultiWindowWM - XOpenDisplay () returned and successfully
opened the display.
winClipboardProc - Hello
DetectUnicodeSupport - Windows XP
winClipboardProc - DISPLAY=127.0.0.1:0.0
winClipboardProc - XOpenDisplay () returned and successfully opened the display.