Nexus

The Nexus is the combined scheduler of resources in UMIACS. Many of our existing computational clusters that are discrete will be folding into this scheduler. The resource manager for this is SLURM and resources will be arranged into partitions of resources where users will be able to schedule computational jobs. Users will be arranged into a number of Slurm accounts based on faculty, lab or center investments.

Getting Started

To use Nexus users will need to have an Account in UMIACS and you will need to follow the directions in the Accounts section. If you already have a UMIACS account then you can skip to the Access section.

Accounts

All accounts in UMIACS are required to be sponsored and can be requested in our Requests application.

Faculty

Please use the Requests application and under PI you should list the current Director of Computing facilities who sponsors all faculty accounts. This is currently derek@umiacs.umd.edu.

Each UMIACS or CSD faculty once they request and receive their UMIACS account can have account to sponsor their students and collaborators. When a user fills out the form they will list their Principal Investigator/Sponsor. Faculty accounts should list the UMIACS Director of Computing (currently derek) while all other users should list their UMIACS faculty member for this sponsorship.

Access

The submission nodes for the Nexus computational resources are determined by department, center or lab affiliation. Users can log into the UMIACS Directory application and select their Computational Resources (CR). They will find a CR that has the prefix nexus and select it to list their available login nodes.

Note - UMIACS requires multi-factor authentication through our Duo instance. This is completely discrete from both UMD and/or CSD Duo instances and users will need to enroll device(s) to access resources in UMIACS. Users will be prompted when they log into the Directory application the first time.

Once users have identified their submission nodes they will be able to SSH into them.

Partitions

• Nexus/Tron - This currently the pool of resources available to all UMIACS and CSD faculty and graduate students. It will provide access for undergraduate and graduate teaching resources.

Storage

All storage available in Nexus is NFS based. These storage allocation procedures will be revised and approved by the launch of Phase 2 by a CSD and UMIACS faculty committee.

Home Directories

Each user account in UMIACS is allocated 20GB of storage in their home directory (/nfshomes/$username). This file system has snapshots and backups available. The quota is fixed however and is not available to increase.

Faculty Allocations

Each faculty will have 1TB of lab space to be allocated to them when their account is installed. We also can support grouping these individual allocations together into a larger center, lab or research group allocations if desired by the faculty. Please contact staff@umiacs.umd.edu to inquire.

This lab space will by default not have snapshots (but are available if requested) and it is backed up.