Login nodes vs. compute nodes
Neon consists of 2 login nodes and 259 compute nodes. Basically, you log in to the login nodes and submit commands to be run on the compute nodes. Two of the compute nodes belong to the Department of Biostatistics; the remaining 257 belong to other researchers throughout the University, or are dedicated for general use (i.e., belong to the University as a whole).
When you log in to Neon, your commands will be running on one of the two login nodes. These nodes are shared by everyone at the University of Iowa who uses the Neon cluster. It is extremely important that you do not run computer-intensive jobs on the login nodes – if the login nodes are occupied, no one can access the compute nodes. So again, do not run computer-intensive jobs on the login nodes – that is what the compute nodes are for.