8. JupyterHub

Web-based Computing

Web-based computing is now available on the Yen servers with JupyterHub without the need to ssh from the terminal or a Git Bash window. JupyterHub is a platform designed to allow multiple users to launch their own JupyterLab instances on a shared system with minimal user effort. It also gives you a terminal, file browser and a way to run Jupyter notebooks with several language kernels including Python 3, R, Julia, MATLAB and SAS.

Getting Started

To get started, open a web browser and visit one of the following links for each server:

You will need to login with your SUNet credentials, and then click on Start My Server. From there, you will have access to the web-based computing services available.

Features of JupyterHub

We recommend taking a look at the official documentation for JupyterHub if you have any questions on the features below!

The JupyterLab interface looks like:

The front panel has a Launcher interface from which you can start notebooks with different language kernels.


Notebooks allow you to write code and execute it within a web browser. Code is written into cells, which can be run in any order, on demand. You can also include text, images, and plots to make your code read like a lab notebook.
Contact the DARC team if you have a language you would like installed.

Note: If you do not see Julia as an option under Notebooks, see this page on how to add it.


RStudio GUI is also available! Clicking this link will bring up a new tab with a web-based RStudio on the Yens.

If you opened up a notebook and want to get back to the Launcher interface to launch other software as well, click the “+” button in the upper left corner:


You can launch interactive consoles from JupyterHub. These will behave very similar to the versions on the Yen servers.


You can launch a terminal from JupyterHub. This provides access to commands you would normally run on the command line on the Yens, but through the web browser.

File Browser

The JupyterHub instances will automatically launch from your home directory on the Yens. Your home directory is a file icon shown by the red arrow:

The current directory is also displayed:

Clicking on the home icon (folder icon), returns the file browser back to your home where you can access any directories that are accessible from your home on the Yens.

Double click on the afs-home and zfs directories in your home directory to navigate to your normal filesystems.

File Upload and Download

One very useful feature of JupyterHub is the ability to upload and download files from ZFS and AFS. First, make sure you are in the proper directory. Then, to upload, click the up arrow on the top left of your screen to select a file.

To download, right click the file you would like, and click “Download”.

Installing Packages

JupyterHub will load packages found in your ~/.local/ directory. If you wish to install Python packages from a JupyterHub notebook, run !pip3 install --user <package_name> in a cell. We recommend using similar user-based installs for other package managers.

Compute Limits

The following limits will be imposed on JupyterHub servers:

  • No more than 320 GB memory usage
  • No more than 12 CPU core usage
  • Servers shut down after 3 hours idle (no notebooks actively running code)

If your processes require more than these limits, reach out to the DARC team for support.

Text File Editor

Finally, you can also edit text files like R scripts directly on JupyterHub. Clicking on Text File icon will open a new file that you can edit. You can also navigate to a directory that has the scripts you want to edit and click on the script to open it up in the Editor.

For example, let’s open up our R script: