Enabling X Graphics from Compute Nodes

Table of Contents

The fastest graphic response from the HPCs will be using SRD or the HPC Portal. However if you want to display graphics on your desktop without the need for middleware, follow these steps to use your own X Server.

1. Install X Server

Linux comes with X in the standard distribution. For Windows, several free products are available, such as Xming (below), VcXsrv or Cygwin. For Mac, install XQuartz (www.xquartz.org).

For Xming, download Xming, Xming-mesa, and Xming-fonts from http://sourceforge.net/projects/xming/files/, and run the installer. At the end of Xming install, check the box to create the Xming icon on desktop.

2. Start X Server

For Xming, simply run it before attempting to open an ssh connection with X11 forwarding. Double-click the Xming icon on your desktop. A dialog box will pop up which will not be used and may be iconified. An "X" application should appear in the system tray.

3. Get a Kerberos Ticket

Obtain a Kerberos ticket using KRB5 for Windows or kinit/pkinit for Linux/Mac.

4. Connect to the HPC System

For Windows, start PuTTY. Enter the connection address, select "SSH", and then in the menu on the left, select Connection > SSH > X11 and check "Enable X11 forwarding." Then click "Open".

For Linux/Mac, ssh to the host using the "-X" (or "-Y") argument.

% ssh -X onyx.erdc.hpc.mil

Check the X11 tunnel by starting an xclock. The xclock should display on your desktop.

5. Tunnel to a Compute Node

To get an X11 tunnel from a compute node, use the following steps:

Request an interactive batch job by using the qsub command, for example:

qsub -l select=1:ncpus=28:mpiprocs=28:ngpus=1 -l walltime=1:00:00 -A project_name -q debug -X -I

Once your interactive session has been started on a shared batch node, test the X11 tunnel with xclock. Now you should be able to run your X application on your assigned compute node.