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