Using Linux Compute Resources

Table of Contents

1. Compute Resources
2. Network connection
3. SSH
4. Screen/tmux
5. Linux/Unix/Shell
6. Lmod
7. X Windows
8. Specific Applications
   1. Abaqus
   2. Ansys
   3. Matlab
9. Other Resources

1. Compute Resources

   1. College Wide
      1. riptide - graduate students only
      2. whirlpool - undergraduate students only
   2. Department level
      1. AAE
      2. ABE - danpatch
      3. CE - moonbase
      4. EE - ececomp, eceprog, ece-batch
      5. IE - barany
      6. ME - americano, bolt, caffeine, coffeeexpress, galileo, nut, tfm, pin, rivet, slot, tab, widget

2. Network Connection

   You will need to be connected to the Purdue network in some way.

   If you are on campus you are mostly liked using a wired connection or wireless.

   If you are off campus or have a Purdue network you can then move on to SSH.

3. SSH

   If you are on a Linux host ssh is typically available.

   For Windows hosts you can use SecureCRT or PuTTy.

   Mac OSX host instructions.

4. Linux/Unix/Shell

   Once you are logged into a host you will be in a Linux environment.

5. Lmod

   The lmod module system is used to load software packaged by ECN If you can't find some software you expect to be installed then read this overview of lmod

   Lmod on Linux Hosts

6. Screen/tmux

   If you have long running jobs the screen or tmux command is very useful.

   1. In a screen session it behaves like a normal shell session but you can "detach" from it. Leave it running. Logout. Then come back to it later

   2. Starting a screen session is a simple as running the screen command

   3. If it's the first time running screen it will give some very brief intro text

   4. If you want to leave the session running, and whatever might be running "inside" that session you will need to "detach" from it by entering ctrl-a then ctrl-d.

   5. You should get a message above your prompt about being detached.

   6. Now you can logout of an ssh session and it won't hang waiting for a process or job to finish.

   7. When you log back into that host you can "re-attach" to that session with the command: screen -R

   8. If you want to run more than 1 screen session, or might have started more than 1 you can list all screen sessions you have with the command screen -ls

   9. You can give you sessions a more meaningful name with the -S flag: screen -S job_20190610

   10. After you've detached from it and want to re-attach you can specify it: screen -R job_20190610

   11. tmux is very similar to screen but has some differences that make it a bit more powerful than screen.

7. X Windows

   Some applications will require a GUI to run. For example, to do pre or post-processing for Abaqus you will need to bring up a GUI to create the model, mesh it, and prepare it before you run your solve/simulation.

   To do this remotely you will need to have an X server running on your local host.

   If you are using Linux it should already be running.

   Max OSX needs a little configuration sometimes.

   With Windows you will need to do a bit more.

   In your ssh client you will want to have "X11 forwarding" enabled. If you are starting ssh from a command line/terminal application be sure to use the -X flag which enables X11 forwarding.

8. Specific Applications

   1. Abaqus

   2. Ansys

   3. Matlab

9. Other Resources

   1. Dr. Keith Cherkauer's Environmental Informatics Wiki

      (Purdue account required to view)

   2. University of Surrey, UNIX Tutorial for Beginners