Overview

X11 forwarding lets you run GUI applications on SeaWulf while displaying them on your local computer: useful for visualization tools and interactive applications with graphical interfaces.

Setting up an X server

Windows (MobaXterm)

MobaXterm includes a built-in X server with SSH integration. Create an SSH session to login.seawulf.stonybrook.edu, enable X11-Forwarding in Advanced SSH Settings, then test with glxgears.

macOS (XQuartz)

Install XQuartz (the standard X11 implementation for macOS; version 2.7.9+ users should enable indirect GLX), then connect with:

ssh -X <your_netid>@login.seawulf.stonybrook.edu

Linux

Most distributions include X11 by default:

ssh -X <your_netid>@login.seawulf.stonybrook.edu

X11 with SLURM jobs

For interactive jobs, request resources with salloc, then SSH into the allocated node with X11 forwarding enabled. For some GUI applications, particularly tools like RStudio, the SeaWulf Desktop app in Open OnDemand delivers better performance.

Note: X11 forwarding operates per SSH connection: switching nodes requires reconnecting with the -X flag.

Troubleshooting

  • Verify your local X server is running
  • Confirm the display variable is set: echo $DISPLAY
  • Test with glxgears or a GUI app like Matplotlib or MATLAB
Applies to SeaWulf