In the instructions below, the term RC-Cluster refers to the Cannon cluster.
The examples below discuss how to run Comsol interactively, or non-interactively in batch mode (without any GUI interface), and how to submit a Comsol job to the RC-Cluster job scheduler SLURM.
Obtain a FAS RC account by visiting:
RC-Cluster (Cannon currently) quick start guide:
Please consult the documentation available at the above link for connecting to FAS systems and familiarizing yourself with the SLURM queue management system. For any help on RC-Cluster (Cannon), contact FAS RC:
- Due to the limited number of COMSOL licenses, we sometimes run out of licenses. If you get a message to that effect, wait for some time before trying again. Also, please log out of any sessions when not in use. If your work requires regular use of COMSOL, please consider purchasing a copy from COMSOL.
- With the introduction of OnDemand VDI (see below), the only supported use of comsol will be on RC-Cluster.
- SEAS Comsol licenses are to be used for only academic non-profit work.
OnDemand Virtual Desktop (VDI)
You can now work conveniently via a browser on RC-Cluster using the virtual desktop infrastructure (VDI) known as OnDemand on RC-Cluster. For more details, please visit:
The best option for working interactively on RC-Cluster is to use OnDemand VDI (see above). If you are authorized to use Comsol, the latest version should be available on OnDemand as an app. Otherwise, open a terminal on the OnDemand remote desktop and proceed as follows.
Comsol versions available via the new module system:
This will display one or more modules. Once you determine a version to use, you can load the module and run comsol. For example, if you choose to use a specific version say comsol 6,
Running comsol in batch via slurm
Batch submissions : 1. Do not submit batch jobs from an OnDemand VDI session. Submit batch jobs from a simple ssh login session to a login node.
2. Do not try to run COMSOL interactively from a login node.
In order to run Comsol mph files in the batch mode (i.e. solving the model without using the GUI interface) you need an input file (usually with extension .mph) created with COMSOL GUI. Once you have an input file (we use, for eg. busbar.mph in the following example), prepare a batch submission script for COMSOL using the following template (called "runscript_comsol.sh"):
You can submit the script to SLURM with:
For further details on using RC-Cluster and SLURM (such as monitoring or canceling your jobs) please visit https://rc.fas.harvard.edu or the list of convenient SLURM commands at https://rc.fas.harvard.edu/resources/documentation/convenient-slurm-commands/.
Comsol documentation is generally found in the COMSOL installation directories. You can find out the installation directory for the particular module you are using with, eg.:
The above command should display something like setenv("COMSOL_HOME","/n/sw/comsol53a") in addition to other locations. In this case, the documentation directory is:
You can view the pdf files in the directoried in the above directory with a pdf reader, such as evince:
Comsol documentation is usually found under html and pdf directories. You can open the pdf documentation (from an OnDemand remote desktop terminal):
Alternatively, you can copy the pdf files to your local desktop/laptop.
As under Documentation, determine the installation directory for COMSOL. For example, for comsol5.3, it is:
comsol examples are in:
For example, the busbar example is in:
You need to copy all the files with busbar in them in order to run the example script:
cp /n/sw/comsol53/applications/COMSOL_Multiphysics/Multiphysics/ busbar* .
(Note the dot (.) at the end on the line above)