Services

Open OnDemand

The Delta Open OnDemand portal is available for use. Current supported Interactive apps: Jupyter Lab, VS Code (Code Server). A terminal is available under Clusters -> Delta Shell Access.

Connect to the Open OnDemand portal in a browser. Log in through CILogon with your NCSA username and password, and NCSA Duo MFA.

Make sure to match the account to charge with the resource partition as shown below. The account names end in -cpu and -gpu; the matching partition would start with cpu or gpu (as in gpuA100x4 interactive). Your input in the Name of account field must match one of your available accounts (CPU or GPU, as appropriate); these are listed under “Project” when you run the accounts command.

Jupyter Lab partition configuration

Open OnDemand Desktop

Open OnDemand provides a VNC service (noVNC) through the “Desktop” Interactive App. Desktop runs in a job on a compute node and gives you access to a virtual Linux desktop that can provide a better graphics experience than X11. Elements to keep in mind:

  • noVNC runs within a container that can see the Delta filesystems ($HOME, scratch, projects, /sw), and the Delta modules are available from the container.

  • You can navigate to a directory and manually launch applications that require a GUI.

  • You may need to set PATH and LD_LIBRARY_PATH from some applications.

  • Some applications may fail if the libraries required are not available in the container.

  • Due to space and time constraints, it’s not possible to build a container that represents all of the software installed in /sw. Consider a “some assembly required” approach if you run into issues trying to launch a program.

  • Use module show <foo> when logged into Delta via SSH or VS Code to discover the PATHs and environment settings you may need to include in the noVNC desktop.

Open On Demand request a Desktop session on compute node

ImageMagick Example

Here is an example showing ImageMagick running from /sw/external/ImageMagick/bin.

Example showing ImageMagick in use via noVNC Desktop.

Customizing Open OnDemand

Debugging Open OnDemand Problems

For internal staff debugging (also useful for new OOD applications): debugging jupyterlab, Open OnDemand.