Skip to content

Open OnDemand

Open OnDemand is a web-based interface that provides easy access to DelftBlue resources through your browser. It allows you to manage files, submit jobs, run interactive applications, and access a remote desktop without the need for SSH command-line tools.

Accessing Open OnDemand

The Open OnDemand portal is available at:

https://login.delftblue.tudelft.nl/

Browser Compatibility

Microsoft Edge might give an "Unauthorized" error. Mozilla Firefox and Google Chrome are recommended and work reliably.

Login

  1. Navigate to https://login.delftblue.tudelft.nl/
  2. Sign in with your TU Delft NetID and password
  3. You will be redirected to the Open OnDemand dashboard

First-time users

Please be aware: Open OnDemand does not trigger creation of the /home and /scratch folders for new users automatically! If your first ever login to DelftBlue is via Open OnDemand, you should get a warning that your home directory was not found.

openondemand home not found

What you should do then is to click "Open Shell" to trigger the "normal" SSH connection, logout of this shell by typing logout, and finally click "Reload Webportal". Now you should be able to access your /home and /scratch directories via Open OnDemand.

VPN Required for Off-Campus Access

Access to Open OnDemand from outside the university network requires TU Delft's EduVPN for "Institute Access". Once connected via VPN, you can access the portal directly.

Features

File Management

The Files menu provides a web-based file browser for your DelftBlue directories:

  • Browse your /home and /scratch directories
  • Upload and download files through the browser
  • Create, rename, and delete files and folders
  • Edit text files directly in the browser
  • View file permissions and properties

openondemand logged in

Shell Access

Open a terminal directly in your browser by clicking "Clusters" → "DelftBlue Shell Access". This provides the same command-line interface as SSH, but accessible through the web browser.

Job Management

Monitor and manage your Slurm jobs through the web interface:

  • View active jobs
  • Check job status and queue position
  • View job output and error logs
  • Cancel running jobs

Interactive Applications

Open OnDemand provides easy access to interactive applications. From the "Interactive Apps" menu, you can launch:

DelftBlue Desktop

A full remote desktop session running on DelftBlue visualization nodes:

  1. Select "Interactive Apps" → "DelftBlue Desktop"
  2. Fill in your Slurm settings:
    • Account (e.g., research-faculty-department)
    • Number of cores (CPUs)
    • Memory requirement
    • Time limit (maximum 4 hours)
  3. Click "Launch"
  4. Wait for the job to start (it enters the queue like a normal Slurm job)
  5. Click "Launch DelftBlue Desktop" when the session is ready
  6. Access your desktop directly in the browser

From the desktop, you can:

  • Open a terminal
  • Load software modules
  • Run graphical applications (MATLAB, ParaView, etc.)
  • Use hardware-accelerated rendering with the visualization node's GPU

For more information on visualization and hardware rendering, see the visualization nodes documentation.

Jupyter Lab

Launch Jupyter Lab or Jupyter Notebook sessions with specialized environments:

  1. Select "Interactive Apps" → "Jupyter Lab"
  2. Choose from multiple pre-configured environments:
    • PyTorch with CUDA support - For deep learning with GPU acceleration
    • TensorFlow with CUDA support - Machine learning with GPU support
    • Multi-language data science - Python, R, and Julia in one environment
    • PySpark - For big data processing
    • Minimal installation - Lightweight environment for basic tasks
  3. Configure your session (cores, memory, time, GPU if needed)
  4. Launch and access Jupyter directly in your browser

For detailed information on using Jupyter on DelftBlue, see the Jupyter documentation.

MATLAB

Run MATLAB in a VNC desktop environment:

  1. Select "Interactive Apps" → "MATLAB"
  2. Configure your Slurm settings (account, cores, memory, time)
  3. Launch the session
  4. Access MATLAB with full GUI support in your browser

The MATLAB application provides a complete desktop environment optimized for computational work.

ParaView

Scientific visualization with GPU-accelerated rendering:

  1. Select "Interactive Apps" → "ParaView"
  2. Configure your session settings
  3. Launch with EGL containers for hardware-accelerated GPU rendering
  4. Access ParaView directly in your browser

ParaView on Open OnDemand uses GPU acceleration for high-performance visualization of large scientific datasets.

RStudio Server

Run RStudio Server with multiple R versions available:

  1. Select "Interactive Apps" → "RStudio Server"
  2. Choose your preferred R version
  3. Configure your session (cores, memory, time)
  4. Launch and access RStudio in your browser

RStudio Server provides a familiar IDE for R programming and statistical computing.

VS Code Server

Web-based VS Code for development directly on DelftBlue:

  1. Select "Interactive Apps" → "VS Code Server"
  2. Configure your session settings
  3. Launch and access VS Code in your browser
  4. Edit code, run terminals, and use extensions

VS Code Server provides a full-featured development environment without needing to install anything locally.

Advantages of Open OnDemand

  • No SSH client needed: Access DelftBlue from any device with a web browser
  • User-friendly interface: Ideal for users less familiar with command-line tools
  • File management: Easy drag-and-drop file uploads and downloads
  • Interactive applications: Launch graphical applications without setting up X11 forwarding or VNC
  • Cross-platform: Works on Windows, macOS, Linux, and even tablets

Limitations

  • File uploads through the browser have size limitations (for large datasets, use SCP/SFTP or other transfer methods)
  • Some advanced SSH features (like SSH key forwarding) are not available
  • Interactive desktop sessions are limited to 4 hours maximum
  • Browser-based desktop sessions may have lower performance compared to dedicated VNC clients for graphics-intensive work

Getting Help

If you encounter issues with Open OnDemand, please contact the DelftBlue support team. For general help with DelftBlue, see the Frequently Asked Questions.