Skip to content

New User Information

When a new user is added to an allocation, a Linux account is created on the HPC cluster, and a welcome email is sent to the user's UMD email address. Please read that email carefully for useful information. If you have not received a welcome message, please check our Getting Access page.

Your Linux User Account

Important

You cannot login to the HPC cluster without being associated with an active allocation. If you are a student, please speak with your PI.

Linux User Account Features

  • Uses university Directory-ID and passphrase for authentication.
  • Provides shell access via SSH to cluster's login nodes.
  • A bash login shell (open a ticket if you want this changed to zsh or tcsh).
  • A home directory with a modest quota (10G) to keep config files
  • Basic configuration "dot files": .bashrc, .bash_profile, .emacs, etc.
  • The .local directory where some apps or modules get installed.

Linux User Account Tips

  • If you receive a Permission denied error when trying to login, either (a) you do not have a cluster account, or (b) you are no longer associated with an allocation. See Getting Access in either case.
  • If you plan to modify your .bashrc or another dot file, make a backup first:
    cp -p .bashrc .bashrc.orig.
  • Use the home_quota command to see usage/quota info. Periodically check the ~/.local and ~/.cache directories, and clean-up unnecessary files.
  • Don't install software or conda environments in your home directory.
  • When you drop out of the university directory, either because you have graduated or your employment has ended, your account is disabled and the login privileges are revoked.

Your Allocations

An HPC Allocation (or a Slurm Account) is a portion of computing resources given to an HPC project. A project can have multiple allocations; a user can belong to multiple projects as well as multiple allocations. Think of a project as your research group/team. The group can receive HPC resources from multiple sources, hence, the multiple allocations within a project. You may also belong to multiple research groups. (See the example below.)

It is quite possible for you to be in multiple allocations when you first get access to the cluster. So, it is important to know against which Allocation/Account to charge your jobs.

Use the sbalance command to see the allocation(s) to which you belong. Let's look at an example output.

Example: sbalance

Example

This shows an example of using the sbalance command to see which allocations you belong to.

login-1:~$ sbalance
Account: janepi-prj-aac (DEFAULT)
Limit:     10.00 kSU
Unused:    10.00 kSU 
Used:      0.00 kSU (0.0 % of limit)

Account: janepi-prj-eng (DEFAULT)
Limit:     13.06 kSU
Unused:    3.43 kSU 
Used:      9.64 kSU (73.8 % of limit)

Account: janepi-prj-paid (DEFAULT)
Limit:     150.00 kSU
Unused:    40.26 kSU 
Used:      109.74 kSU (73.2 % of limit)
    User joeuser used 0.0001 kSU (0.0 % of total usage)

Account: hpcintro-aac (DEFAULT)
Limit:     9.86 kSU
Unused:    9.86 kSU 
Used:      0.00 kSU (0.0 % of limit)

The login~1:~$ is the shell prompt; your prompt may look different (due to being on a different login node, in a different directory, or you might have customized your prompt). The Account: field gives the name of the allocation.

In this example, you have access to four allocations, three under janepi-prj, a fictitious project owned by a PI named Jane, and the fourth allocation hpcintro-aac which belongs to the hpcintro project. The command also lists the limit, usage, and amount of the allocation that is unused, all in units of kSU.

Which Allocation Account should I use and how to specify?

Now that we know our allocation names, when we submit a job later in this guide, we can specify the correct account.

  • Use the -A sbatch directive to specify the allocation/account you want to charge against. Add a line similar to the following to your job submission script:
    #SBATCH -A janepi-prj-paid

We will see how to write a job submission script later.

Previous: The Basics Next: Connecting to the Cluster