Logging to a cluster

Computers are managed by an Operating System (OS). The HPC cluster nodes usually run some kind of Unix-like OS. The HPC clusters listed on this site run Red Hat Enterprise Linux (RHEL) - a distribution of Linux.

While there are multiple Linux desktop environments (DE) that provide Graphical User Interface (GUI) similar to Windows or MacOS, HPC clusters usually do not have such DEs running. Instead users log into clusters using an ssh client program and type Command Line Interface (CLI) commands to tell the computer what to do. The ssh client program is available on Linux, MacOS and newer MS Windows machines (in PowerShell). For older Microsoft Windows machines, we recommend using PuTTY ssh client.

Cluster-specific detailed login instructions can be found in the cluster's User Guide, see menu on the left.

Several methods are used to enhance security of the HPC systems at ISU. First, the computer from which you ssh to the cluster needs either to be on the iastate.edu network or use the ISU VPN installed from http://vpn.iastate.edu. Additionaly, Multi Factor Authentication (MFA) is used. The first factor is your ISU password. The second factor is a Verification code generated by a Google Authenticator (GA) app running on your mobile device. Thus if someone gets access to your ISU password, they will also need access to your GA account to be able to login to the system as you, and vice versa.

After your ISU NetID has been added to a cluster's ASW access list, you can ssh to the cluster using your ISU password. You will most likely be asked if you want to store the cluster's host key. Answer YES.

If you don't plan to access one of the Research HPC clusters, you may skip the next page (MFA) and go directly to the Command-line Interface (CLI) page.

Next: Multi Factor Authentication (MFA)