Quick Start to Explorer¶

This page highlights the major changes between Discovery and Explorer and provides a few recommendations for a smooth transition.

PIs can Add and Remove Users¶

PIs (staff, research scientists, teaching professors, faculty) can now add and remove members from their storage spaces and partitions. For new users, this will create their account on the cluster and add them to the PIs storage space.

Simply login to the terminal via ssh or select the option “Clusters -> Explorer Shell Access” on the OOD.

# Get on a compute node
srun --pty bash
# Run the command 'project'
project <projectname> add members <username>

Read more about managing /projects here

New Storage Directory¶

All of your data that was in Discovery will be in Explorer.

On Explorer, our performant storage directory is called /projects.

If you had a storage space for performant storage on Discovery, you would want to change the paths in your scripts from /work to /projects. If you would like a new directory in /projects, please request one.

Courses Directory¶

If you are teaching in the Spring 2025 term, you will only be able to access your course materials (i.e., /courses directory and OOD applications) from Explorer.

If you get a “Permission Denied” error when trying to cd or otherwise access your space in /courses please check that you are logged in to Explorer, and please select “Restart Web Server” from the ? icon.

Transferring Files¶

The hostname for the transfernode (xfer) will continue to be: xfer.discovery.neu.edu. Please see our documentation on transferring files for example commands.

New Software¶

There is a lot of new software on Explorer. Please see what we offer as a module and as a container image. If you don’t see software that you would like to use on the Explorer cluster, please fill out a software request form.

Modules¶

All of the modules on Explorer are new. Some versions may have changed since the one you used on Discovery. Thus, module load commands will need to be updated.

Modules should be loaded in sbatch scripts.

For interactive sessions using srun, you can create an environment file (a text file with your module load commands) to source environmental parameters for interactive sessions. For example, if we saved several module load commands in a file called “env_file.sh”. We could execute this file in an interactive session with the command “bash env_file.sh”.

Important

Any “module load” commands in your .bashrc that load Discovery modules may result in a “MODULE NOT FOUND” error in Explorer. Modules loaded in your .bashrc can also lead to conflicts in your environment.

We recommend removing all module load commands from your .bashrc

Container Images¶

Apptainer is the container run-time engine on Explorer and is installed system-wide (i.e., there is no module for apptainer).

We have many newly added container images at /shared/container_repository/explorer/

If you had an image that was pulled to Discovery using Singularity it should still work as expected on Explorer, though there may be some exceptions. One of the advantages of container images is their portability.

Software Compiled on Discovery¶

We recommend recompiling software on Explorer that was compiled on the Discovery cluster. If you need assistance, please reach out to the Research Computing Team by emailing rchelp@northeastern.edu.

Conda Environments¶

Conda environments that were built in Discovery may work in Explorer. A case where they may not work is if you had to load modules on Discovery to build and run your conda environment, and those same modules are not on the Explorer cluster (or their version has been updated). We recommend trying your conda environments on Explorer. If you run into error, try rebuilding the environment, or contact Research Computing by emailing rchelp@northeastern.edu

Please see our documentation on conda environements for more information.