The NCSU recommended approach to running remote X11 applications from a local Windows machine is through the use of StarNet X-Win32, for which a student license is freely available from EOS. The X-Win32 technique works well for most applications, but for low-bandwidth connections, VNC provides an alternative, lightweight connection option.

This article describes the procedure for instantiating a VNC server on a Linux Lab Machine (Realm RHEnterprise Linux 4) through the Virtual Computing Lab (VCL). It assumes that you are already familiar with the use of both PuTTY and UltraVNC, and simply need additional information on setup nuances particular to NC State.

One Time Initial Configuration

PuTTY is used to bypass the RHEnterprise firewall by using SSH and its port forwarding capabilities. Create and save a PuTTY profile with the following SSH tunnel:

SSH to the your VCL reservation with your NCSU login and password (eg, 152.1.21.221, login tbarik). Type ‘vncpassword’ at the command prompt and set your desired VNC password:

dan255-21-222% vncpasswd
Password:
Verify:

Next, edit the xstartup file found under the .vnc directory and uncomment the following lines so that they appear as follows:

# Uncomment the following two lines for normal desktop:
unset SESSION_MANAGER
exec /etc/X11/xinit/xinitrc

This will allow the VNC server to load a proper window manager, for which GNOME is the default on NCSU.

New VCL Reservations

For every new VCL reservation, start the VNC Server, specifying your desired resolution. By default, this is 800×600, but can be easily changed with the geometry argument:

dan255-21-222% vncserver -geometry 1152x864

New 'dan255-21-222:1 (tbarik)' desktop is dan255-21-222:1

Starting applications specified in /ncsu/tbarik/.vnc/xstartup
Log file is /ncsu/tbarik/.vnc/dan255-21-222:1.log

You can double-check the log file created above to confirm the port number of 5901:

Sat Feb  2 18:53:02 2008
vncext:      VNC extension running!
vncext:      Listening for VNC connections on port 5901
vncext:      Listening for HTTP connections on port 5801
vncext:      created VNC server for screen 0

Finally, open UltraVNC Viewer on your local system. For VNC Server address, enter:

 127.0.0.1:5901

If all goes well, you will be connected to your Realm RHEnterprise Linux session, as illustrated in this screenshot.