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NERSC is the National Energy Research Scientific Computing Center, a high-performance computing (HPC) and storage facility for research sponsored by, or of interest to, the U.S. Department of Energy (DOE) Office of Science. To use it you need a NERSC account tied to a project that holds an allocation, and the allocation comes from a request reviewed by a DOE Office of Science program. This guide is for researchers and research-office staff who need to know what NERSC offers and what the path to a first job looks like.
What NERSC is
NERSC’s own documentation describes it as providing High Performance Computing and storage facilities and support for research sponsored by, or of interest to, the DOE Office of Science. Its flagship system is Perlmutter, an HPE Cray EX (Shasta) machine. The NERSC architecture page describes it as a heterogeneous system of 3,072 CPU-only nodes and 1,792 GPU-accelerated nodes, connected by a Slingshot 11 dragonfly network, with an all-flash scratch file system of about 44 PB. Perlmutter is named for a Berkeley Lab astrophysicist.
Who it serves and what the nodes contain
NERSC is a DOE Office of Science facility, and access is organised around projects that hold allocations. One rule matters for grants offices: NERSC supports only open research intended to be published in open scientific journals, so purely proprietary work does not fit. For a wider view of how the Office of Science funds computing research, see DOE ASCR (Advanced Scientific Computing Research).
| Perlmutter node type | Count | Per-node hardware (NERSC documentation) |
|---|---|---|
| CPU-only | 3,072 (system total) | Two AMD EPYC 7763 processors, 512 GB DDR4 memory |
| GPU, 40 GB variant | 1,536 | One AMD EPYC 7763 and four 40 GB NVIDIA A100 GPUs |
| GPU, 80 GB variant | 256 | One AMD EPYC 7763 and four 80 GB NVIDIA A100 GPUs |
How to get access: allocation, account and first steps
Access is two linked things: a project with an allocation, and a user account attached to that project. The steps below follow NERSC’s account documentation and the ERCAP page.
- Get a project. Ask your principal investigator (PI) for the project name, which is usually the letter m followed by four digits. If there is no project, the PI applies for an allocation. A research grant that supports the DOE Office of Science mission is expected, and Exploratory Awards exist for new projects.
- Submit the account form. NERSC uses a web portal called Iris. Choose the option for a new NERSC account and submit the Create a NERSC Account form. Existing users use the option for a current account.
- Wait for identity vetting. NERSC documents this as taking up to a week.
- PI approval. The PI or a PI Proxy approves the request in Iris.
- Set the initial password. You receive an email link that expires after 24 hours.
- Accept policies and set up multi-factor authentication. In Iris, accept the NERSC Appropriate Use Policies and set up Multi-Factor Authentication, which NERSC states is required for all users. Iris is also where allocation balances and login shell are managed.
Requesting an allocation (ERCAP)
Allocation requests go through ERCAP, the Energy Research Computing Allocations Process. The PI needs a NERSC account (requested in Iris as a new PI ERCAP access account) and is responsible for the request; Senior Investigators and Authorized Preparers can help prepare it. Initial requests can be submitted at any time and renewals are annual. The applicant selects the DOE Office of Science program that will review the request; projects not funded by DOE explain in two to three sentences how the work aligns with an Office of Science program mission.
After the account exists
NERSC’s getting-started documentation covers connection through SSH to login nodes, ThinLinc or Federated Identity; software through the module system (Lmod); Python via Anaconda; and batch jobs through Slurm, where most jobs use srun in place of mpirun. Interactive Slurm jobs and a Jupyter service are also available. Help starts with the documentation, then a ticket at help.nersc.gov.
Data storage: planning for a data management plan
If your funder requires a data management plan, the storage tiers matter. NERSC documents three:
| Tier | Role | Note from NERSC documentation |
|---|---|---|
| Community File System (CFS) | Global file system for sharing | Intended for shared project data |
| Scratch | High-performance working space | Files inactive for more than 8 weeks are subject to being purged |
| HPSS | Archive | Long-term storage |
Strengths and limits
- Strength: allocation is awarded through a documented, annual-renewal process, and the system pairs CPU and GPU nodes in one machine.
- Limit: access depends on alignment with a DOE Office of Science program and on open, publishable research.
- Limit: scratch is not a safe place for the only copy of results, given the purge policy.
- Limit: the identity-vetting step can take up to a week, so build it into project start dates.
Alternatives
NERSC is one of several U.S. government computing and research resources, and the right choice depends on the sponsoring agency and the program that funds the work. The table points to the CASRAI pages that cover the other routes; check each facility’s own documentation for its current systems and access rules.
| Alternative | When to look at it | CASRAI page |
|---|---|---|
| El Capitan | You want to understand another large U.S. government supercomputer | El Capitan supercomputer |
| Pacific Northwest National Laboratory | You need a different DOE national laboratory and its user-access route | Pacific Northwest National Laboratory user guide |
| DOE ASCR | You want the Office of Science program that funds computing research | DOE ASCR |
| NSF-funded route | Your project is funded by NSF rather than DOE | NSF vs DOE grant requirements |
FAQ
What does NERSC stand for?
National Energy Research Scientific Computing Center.
Who can use NERSC?
Researchers on a project with a NERSC allocation, doing open research that supports or is of interest to the DOE Office of Science.
Can I use NERSC for proprietary work?
No. NERSC states it supports only open research intended to be published in open scientific journals.
How often are allocations renewed?
Annually through ERCAP; initial requests can be submitted at any time.
Where do I manage my account?
In Iris, NERSC’s account portal, which also handles multi-factor authentication and allocation balances.
Sources
- NERSC Documentation home, docs.nersc.gov (read 2026-11-07)
- NERSC, Perlmutter architecture, docs.nersc.gov/systems/perlmutter/architecture (read 2026-11-07)
- NERSC, Accounts, docs.nersc.gov/accounts (read 2026-11-07)
- NERSC, Getting Started, docs.nersc.gov/getting-started (read 2026-11-07)
- NERSC, ERCAP request form, docs.nersc.gov/allocations/ercap_form (read 2026-11-07)
