Login Nodes

SeaWulf provides multiple login nodes which can access different sets of computing nodes:

• login.seawulf.stonybrook.edu - 28core
• milan.seawulf.stonybrook.edu - 40core, 96core, HBM-96core
• xeonmax.seawulf.stonybrook.edu - 40core, 96core, HBM-96core

See the Login Nodes FAQ for details.

Basic Linux Commands

Some essential commands to navigate the cluster:

• mkdir <directory_name> — create a folder
• ls — list files in current directory
• pwd — show your current directory
• cd <path> — change directories
• touch <filename> — create a blank file
• cat <filename> — display file contents
• rm <file> — remove a file; rm -r <folder> removes a directory recursively
• history — view command history; !<number> re-executes a command
• grep "<pattern>" <filename> — search for patterns in a file

Modules

Modules allow you to manage environment variables and access software easily:

• module avail — list available modules
• module load <module_name> — load a module
• module list — list loaded modules
• module unload <module_name> — unload a module
• module help — show module help and usage

Special software requests can be submitted via the IACS ticketing system.

SLURM Job Management

Compute-intensive tasks run on compute nodes using SLURM. Login nodes are not for heavy computation.

Interactive Jobs

module load slurm
srun -N 1 -n 28 -p short-28core --pty bash

• -N — number of nodes
• -n — number of tasks
• -p — partition/queue
• --pty bash — interactive shell

See the SeaWulf Queues page for a full list of available queues and resource limits.

Automated Jobs

Create a job script (example below) and submit with sbatch:

#!/bin/bash
#SBATCH --job-name=test
#SBATCH --output=res.txt
#SBATCH --ntasks-per-node=40
#SBATCH --nodes=2
#SBATCH --time=05:00
#SBATCH -p short-40core
#SBATCH --mail-type=BEGIN,END
#SBATCH --mail-user=jane.smith@stonybrook.edu

module load intel/oneAPI/2022.2
module load compiler mkl mpi

cd /gpfs/projects/samples/intel_mpi_hello/

mpiicc mpi_hello.c -o intel_mpi_hello
mpirun ./intel_mpi_hello
    

Use squeue to check status, scancel <jobid> to cancel.

DUO Two-Factor Authentication

SeaWulf requires DUO authentication. Approve login requests on your enrolled device.

More info: DUO Security