To know more about on how to Use Interactive Sessions in OnDemand please click here



Academic Cluster (UB-HPC) Desktop

This app will launch an interactive desktop on one or more compute node. You will have full access to the resources these nodes provide. This is analogous to an interactive batch job. The longest allowable wall time for these nodes is 72 hours (except the debug partition which is 1 hour).

However, you can select less if desired and this will almost certainly decrease your wait time.



  1. Slurm Account: Your default Slurm account will be used if nothing else is entered.  To see what Slurm accounts you have access to, use the 'slimits' command in a terminal window.
  2. Partition: Use the drop-down bar to make a selection for partition.  To get more details about the partitions in the academic cluster click here.
  3. QOS: Quality of Service value - this will be the same as partition unless you have access to a QOS priority boost.  More info can be found here.
  4. Number of hours: Most partitions have a max walltime of 72 hours.  Debug partition max=1 hour.
  5. Number of nodes: Only select more than one node if you're sure your program can run on multiple nodes.


In this example, we've started up an Academic Cluster (UB-HPC) Desktop.  Once you click the Launch button, you will be redirected to the session information where you can see the status of the job.  This one is queued:



If you have elected to receive an email when your job starts, you can leave the CCR OnDemand portal until the email arrives and then log back in to open your session.  


As it is preparing to start you will see:


When a session is ready to launch, it will look like this in the Interactive Sessions section of CCR OnDemand:


Click on the blue "Launch Academic Cluster (UB-HPC) Desktop" button and you will see your desktop window on the node you've been allocated:




You are now logged into an interactive desktop session on a node in the CCR academic cluster.  You can begin your work!  



If this is your first time starting an interactive desktop session, you may be prompted with this pop-up:



Please click "Use default config"



NOTE: If your session starts and does not display a menu or icons on the bottom (as shown in these screenshots), check out this troubleshooting article



To start a terminal window, click on the window icon at the bottom of your screen, shown here:




This is a terminal window and where you will type all of your commands.  If you are unfamiliar with UNIX commands, we recommend you view the following articles:

Basic UNIX

UNIX File Transfer


To learn more about launching GUIs for COMSOL, MATLAB, StarCCM, and ABAQUS click here.


For information about where files are stored, how to check your quotas, and how to purchase additional storage, please see:

Storage and Quotas


All software available for use on CCR servers is listed here:

Current Software Information

How do I install software?


Still unsure what to do next?  Schedule an appointment with one of our computational scientists for a training session by submitting a help request.


To know more about deleting a running session click here.