Open OnDemand

Open OnDemand is an NSF-supported web-based job management system accessible through a standard browser.

Portal URL: https://interactive.hpc.caltech.edu

Note

The portal is reached via interactive.hpc.caltech.edu and served from the vislogin.hpc.caltech.edu backend. If you’re debugging DNS or VPN issues, both hostnames need to resolve from your network.

Features

File Management - Upload, download, move and delete files through the web browser
Code Editor - Modify files without launching a shell session
Terminal Access - Command-line interface directly from the portal
Job Monitoring - Real-time status tracking of pending and running jobs
Job Templates - Preset submission templates with customization options
Desktop Streaming - Full XFCE Linux desktop via web for GUI applications like MATLAB

Getting Started

Important

New users must first log in via SSH to initialize home directories before using Open OnDemand.

Navigate to https://interactive.hpc.caltech.edu
Log in with your Caltech credentials
Complete multi-factor authentication (Duo)

Interactive Desktop

Launch compute node desktops for GUI-intensive work:

Go to Interactive Apps in the menu
Select Desktop
Specify duration (maximum 7 days) and CPU cores (minimum 4)
Click Launch

Tip

Google Chrome provides optimal performance. The interface adjusts to your browser window size.

Troubleshooting

PATH Conflicts

Library loading errors may occur due to PATH conflicts in shell configuration files. Review your ~/.bashrc and ~/.bash_profile for conflicting entries.

Browser Issues

Clear browser cache and cookies
Update to the latest Chrome version
Try a different browser

File Upload Failures

Usually related to storage quota limits. Check your quota:

hpcquota

“Request Header Too Long” Error

Clear cookies for the HPC domain in your browser settings.

Home Directory Quota

Limited home directory space can affect OOD functionality. Move large files to group storage.

Support

Contact help-hpc@caltech.edu for assistance.