JupyterHub is a shared, web-based platform that gives each user access to their own private Jupyter environment on a central server. It provides access to JupyterLab, a modern interface for working with code, data, and documents — including Jupyter Notebooks, which are interactive documents used for data analysis, scientific computing, and software development.
JupyterHub on the RACC2 removes the need to manually start a Jupyter Notebook or JupyterLab session and then open it in a web browser. Instead, you can use a browser on your local machine (currently only supported via NX) to log in to a persistent web portal.
Under the hood, sessions are transparently scheduled on the interactive login nodes, in the same way as SSH login sessions, with the same generous resource limits: 12 CPUs and 256 GB of RAM per user session. Please be considerate with memory usage. The memory limit is intended to prevent an individual user from accidentally overwhelming the server, not to ensure strict fairness or protect against total memory exhaustion.
Use the following procedure to start a JupyterHub session on the RACC2:
In a JupyterLab session launched via JupyterHub, you will find kernels corresponding to relevant centrally managed Conda environments. A kernel is the backend process that runs your code in a notebook. Each kernel is tied to a programming language and software environment. You can also register your personal environments as kernels.
Instructions for creating personal Conda environments can be found here: https://research.reading.ac.uk/act/knowledgebase/python-on-the-academic-computing-cluster/
module load anaconda source activate myenv
conda install ipykernel
python -m ipykernel install --user --name myenv --display-name "myenv"
After completing these steps, your personal environment will appear in the Kernel > Change Kernel menu in JupyterLab under the name “myenv”, and as an icon to start a Notebook, or Jupyter Console (you might need to reload your session).
There is also an R environment available within JupyterHub. This is the same R environment which is available on the RACC2. R packages can be installed in your home directory. Advanced users might also use Conda to create multiple R environments, and install dependencies needed to build R packages. However, we are not routinely supporting R on JupyterHub at present.