Open OnDemand, an open source software project started in June 2015 with
support from NSF, provides HPC access through a web portal as an
alternative to the command line for accessing and utilizing HPC
resources. Development of this interface was in response to an immediate
need to help less compute savvy users leverage the power of HPC in
their research. It was based on OSC’s in-house OSC OnDemand portal
deployed in January 2013. Since 2015, OnDemand has evolved into a more
flexible and extendable web portal installed at more than a dozen
academic and commercial institutions.
The primary goal of OnDemand is to lower the barrier of entry and
ease access to HPC resources for both new and existing users. OnDemand
accomplishes this by providing a rich set of core web applications which
leverage HTML5 standards and are securely hosted behind a web proxy
providing federated authentication. All the user needs to access
OnDemand is a modern web browser and their HPC credentials. OnDemand
provides HPC centers a “zero-install” (i.e., no native SSH, SFTP, or VNC
client necessary) and single sign-on (SSO) solution for their users.
A key feature of OnDemand over a traditional web service is the
per-user web server model where all the web applications are run as the
Linux user. This leverages the Linux kernel for security and accounting
and greatly simplifies app development, making OnDemand a very
attractive choice as an app platform. OnDemand currently supports web
applications written in Ruby, Python, and Node.js and includes the
OnDemand AppKit library which extends the capabilities of web
applications by providing a unified interface to a variety of resource
managers: Torque, Slurm, LSF, and PBS Pro. OnDemand also supports
Interactive Apps, which consist of a batch job that launches a web
application server on a compute node, pre-configured to allow the user
to connect directly to it from within their browser. Due to the
considerable demand for Interactive Apps (in particular Jupyter Notebook
and RStudio Server) from users as well as from our project partners,
the Dashboard comes with a plug-in style wrapper designed to streamline
the Interactive App development process.
OSC’s OnDemand installation has seen remarkable growth since it was
first released in September 2016, being used by more than 1,500 distinct
OSC users executing over 100,000 app launches! In the last year, it has
more than doubled its active monthly user count. Even more impressive
is that less than a year after launch, a majority of OSC users used
OnDemand instead of traditional mechanisms such as PuTTY (ssh) and
FileZilla (sftp). This project has now been installed and put to use at
more than a dozen different commercial and academic institutions
including Pittsburgh Supercomputer Center, University at Buffalo,
University of Utah, University of Arizona, Texas A&M, and NorTech.