Frequently Asked Questions
If you have general questions that are not included in this page or in the rest of the documentation, please email hpc@umass.edu. To troubleshoot more specific errors and issues, see Troubleshooting.
Connect to Unity
How do I connect to the Unity platform and begin using it?
There are multiple ways to connect to Unity:
- Unity OnDemand is the simplest and most convenient method of connecting because it allows you to login through your browser.
- SSH Connection is the most traditional method of connecting to Unity, especially for experienced Command Line Interface (CLI) users. SSH connection allows you to connect to Unity in your terminal.
- Visual Studio Code Desktop allows you to connect to Unity using the Remote-SSH feature, which is useful for users that prefer to use VS Code as their editor.
- PuTTY is a convenient way to connect to Unity that is available to Windows users. See the SSH Connection guide for instructions on how to connect with PuTTY.
Software and Tools
Where can I find software to use on Unity?
Most of our software is package installed and is available by default.
Unity OnDemand provides JupyterLab, Matlab, RStudio, Mathematica, and a XFCE, a general purpose interactive desktop environment.
Non standard and version specific software are available as modules.
- To print all available modules, use the command
module av. - To filter the available modules, use
module av <name>. - To load a module and gain access to its binaries (executables), use
module load <name>.
To install additional software, see our guide on conda environments.
I’m looking for xyz software; could you install it?
Most software that is requested is free for use and can be installed for you. To request software, please fill out our software request form. If the software you want is licensed, we may be able to help since the campus often has site-wide licenses for many applications.
Can I run containers on Unity?
Yes! We support Apptainer (formerly Singularity) containers, which are fully compatible with Docker images. Run module load apptainer/latest to access it.
Storage and Hardware
How much storage do I get on Unity and is it backed up?
Refer to our storage documentation.
We do not provide backup solutions by default.
We take snapshots of /home/ and /work/ every day at 1AM, but delete them after two days.
How can I extend the 30-day scratch workspace? Mine seems to have expired, and I can’t access it.
For information on how to extend a workspace, see the HPC Workspace documentation.
I’m a PI, and I would like to purchase hardware to buy-in to Unity.
Great! Send us an email and we’ll be happy to help. We are very flexible when it comes to the needs of research labs.
Job Management
I’m part of multiple PI groups; how can I make sure I’m doing my work under a certain group and not a different one?
To change an association for a job, use the command --account=pi_....
How can I check the resource use of my job while it’s running?
To connect to the node where your job is running and start an interactive shell, use the command srun --overlap --pty --jobid X /bin/bash.
Tools like nvitop will only show the GPU(s) assigned to the job you attached to (not all your jobs on that node), while htop -u $USER will show all of your processes’ CPU and memory usage. Use scontrol -d show job X to see which CPU cores your job is using.