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ParallelCluster (PC) and Open OnDemand (OOD) FAQs

1. I've clicked on the button to start my Jupyter/Rstudio/VSCode session, and the window that appears is completely blank. What do I do?

This delay may be due to some sluggishness in spinning up the server process that runs that client interface for your application. Note that this is unrelated to the other content display problemn we have with the OOD Dashboard and OOD terminal windows.

Do the following:

  1. Pause for about 10 - 30 seconds to wait for the client to connect to the launched server process.
  2. If the window remains blank after 60 seconds, select the Refresh button on your browser, again waiting about ~30 seconds.
  3. If the window still remains blank, please follow the instructions directed by the OOD team at this help doc.
  4. If the problem still persists, contact the ReD team for support.

2. I've submitted a job, and I am still waiting for the job to start, even after 10+ minutes. What do I do?

We have seen this more frequently, esp. after the recent AWS' major outage. On occasion, PC may have problems provisioning a node, resulting in long wait time for the job to start, as seen from the Open OnDemand UI. If you're job has not started about 5 to 10 minutes, open a cluster terminal window (Clusters > Shell Access) and enter the command sacct -D.

If multiple lines are shown for the same job ID, this indicates that the node had to be reprovisioned or rebooted as the node health check had failed. If this situtaion lasts more than 15 minutes, start a new job and kill the other one.

3. Can I send email messages when my SLURM job starts or ends?

Sorry, you cannot use job notification emails, as communcations from inside the environment to the outside could contain sensitive information.

4. In the OOD Files menu, where are my lab folders? Why can't I upload, download, edit, or view files?

Certain, default features in OOD have been disable for security reasons or to support compliance by preventing direct import/export of data from the environment. Please see this information for more details.

Updated: 12/22/2025