Introduction

To launch OnDemand, go to: scc-ondemand.bu.edu

SCC OnDemand is the recommended way to access the BU Shared Computing Cluster (SCC) over the web using a graphical, menu-based environment that doesn’t require using an SSH client. It is particularly well suited to applications like MATLAB, RStudio, and Jupyter Notebook which have a graphical component. Additionally, OnDemand allows you to upload and download files, launch applications, view disk quotas and do many other things on the SCC.

Open OnDemand was developed ten years ago by the Ohio Supercomputing Center and is now in use at many universities. The BU version is customized for the SCC. Please send email to help@scc.bu.edu if you have any questions or concerns.

Getting Started

In order to access OnDemand, you must have an SCC research account or a Linux Virtual Lab/scc-lite account; with just the latter your usage will be limited. We recommend using recent versions of Chrome or Firefox; Safari and Edge might work for some of the apps, but they are not fully supported. Accessing OnDemand from a phone or tablet is possible but also not fully supported.

You will be prompted to log in with your BU login name and Kerberos password. You will also be required to use Two-Factor Authentication with Duo Security. This is the same authentication mechanism used by BUWorks and the StudentLink. If you have previously used Duo to authenticate to either of those services, all of your registered devices will work with SCC OnDemand. If you have not registered a device for Duo authentication, please go to https://www.bu.edu/tech/support/duo/enroll-device/ to register and set up one or more methods of authenticating using your cell phone, office phone, tablet, and/or other options. If you use the appropriate checkbox, you should only need to re-authenticate with Duo every 30 days for a given web browser.

After you run OnDemand for the first time, a directory called ondemand will be created in your SCC home directory. Do not remove or edit the contents of this directory.

Logging Out and Ending Sessions

There is a difference between logging out of your web browser’s connection to OnDemand and ending sessions/jobs that are running under OnDemand. In order to quit OnDemand in your web browser, there is a “Log out” link in the upper right of the screen; you should particularly make sure to use this when you are done accessing OnDemand from a public computer.

Note that if you have any interactive applications or jobs running, logging out of OnDemand or closing your browser window will not end them and they will continue using SUs. This feature means that you can log back into OnDemand using a different computer, see your active sessions in the “My Interactive Sessions” tab, and reconnect to an existing session to continue your work. Please see the page on My Interactive Sessions for how to delete/end running sessions that you no longer need.

OnDemand sessions will run until they either reach their time limit or are deleted. When running programs that do not require interactive use you should submit a batch job.

OnDemand Tabs

The top of the OnDemand window has several tabs that give access to the various capabilities of the portal. These are described below.

Interactive Applications

Use the “Interactive Apps” tab (documentation) to launch a graphical application such as RStudio or MATLAB. In addition to the applications listed in the menu, you can also launch other applications by first launching the “Desktop” app and then, after connecting to the Desktop session, use the terminal to module load the applications of interest and then run them.

My Interactive Sessions

The small icon My Interactive Sessions to the right of “Interactive Apps” launches the “My Interactive Sessions” app (documentation) which shows all OnDemand sessions you currently have running with information on time limits and which SCC node each session is running on. It also lets you connect to those sessions and delete/end them. Depending on the width of your web browser window, you may or may not see the words “My Interactive Sessions” next to the icon for this option in the navbar.

Login Nodes

Use this tab to open a shell (command-line window) on any of the primary SCC login nodes (scc1.bu.edu, scc2.bu.edu, geo.bu.edu, or scc4.bu.edu). These shells do not support X Forwarding so you will not be able to launch graphical applications such as MATLAB or RStudio from them. Use the “Interactive Apps” tab to launch graphical applications.

Managing Files

To upload, download, create, edit, or move files using the OnDemand GUI, click on the “Files” tab (documentation) within OnDemand.

Quotas

Use the “Quotas” tab to see the usage and quotas for your home directory and all Project Disk Space directories you have access to. The data on this page is similar to the output you would get by running the commands quota and pquota on the SCC. The Project Disk Space quotas listed are for the project as a whole; if you have an individual quota it will not be listed here but can be seen from your Research Computing User Information page. There is additional information on how to read this data on the Storage Quotas web page.

Help

The “Help” menu lets you access this documentation, contact RCS staff for help, check the status of the SCC in case there is an issue, and restart the PUN web server that serves your OnDemand session in case your session has a problem.

Miscellaneous

  • Copy & Paste in OnDemand
    If you are working within a “Login Nodes” shell or a “Servers” session from “Interactive Apps”, cutting and pasting should behave normally.However, if you are working in a “Desktops” app (Desktop, MATLAB, Mathematica, etc…) cutting and pasting is more involved.
  • Control/Command Character Sequences
    Some control/command character sequences may not work properly in OnDemand as they may be interpreted by your web browser instead of being passed on to your OnDemand app. Ctrl+w in particular may very well cause issues as it is commonly a shortcut to close the web browser tab. In the Emacs editor, you can instead use esc-x kill-region

FAQ

There is a separate Frequently Asked Questions page to answer common questions about OnDemand.