====== Comsol on Caviness ======

<note warning>Comsol will not work on Lustre.  Please use  [[:abstract:caviness:filesystems:filesystems#workgroup-storage|workgroup storage]] ($WORKDIR) on Caviness.</note>

Comsol requires user(s) to purchase a license in order to gain access to the license server to actually use the software. 

This requires some amount of setup for each workgroup to do in order to use Comsol on Caviness.  One can define an environment variable that can be set to the license server "path" (''<port>@<hostname>'').  This is done as follows.

<code bash>
export LMCOMSOL_LICENSE_FILE=port@hostname
</code>

However, there's a shortcut discussed at the top of Comsol's VALET package definition on Caviness as shown below:

<code bash>
#
# You MUST set LMCOMSOL_LICENSE_FILE in your environment to point
# to your Comsol license server.  Workgroups can create the file
#
#   ${WORKDIR}/sw/comsol/license-server
#
# containing the FLEXlm license path they use for Comsol, and
# this package will set LMCOMSOL_LICENSE_FILE to the contents of
# that file.
#
</code>

Comsol VALET package has a scripted component to their VALET actions. It checks for the file mentioned above and sets the appropriate license environment variable to that file's content. By putting the above file in the directory specified above, it is locked-down to the workgroup only and all members in the workgroup have access to Comsol, and it doesn't require any modification to the workgroup members login files or job scripts. See [[abstract:caviness:install_software:workgroup-sw|Workgroup Software Installs on Caviness]] for help in understanding how to create the necessary workgroup directories referred to above.

The VALET package for Comsol is available to everyone on Caviness, and will load as expected.  However, in order to use Comsol, it will only work if the above file exists in the proper directory location or the environment variable ''LMCOMSOL_LICENSE_FILE'' with the appropriate license server ''<port>@<hostname>'' information which is only provided upon purchasing a license. To load the default version of Comsol, use

<code bash>
vpkg_require comsol
</code>

Use ''vpkg_versions comsol'' to see a list of all available versions of Comsol installed on Caviness. For example 

<code bash>
$ vpkg_versions comsol

Available versions in package (* = default version):

[/opt/shared/valet/2.1/etc/comsol.vpkg_yaml]
comsol  Model and simulate any physics-based system
* 5.3a  Version 5.3a (all components)
  5.4   Version 5.4 (all components)
  5.5   Version 5.5 (all components)
</code>

lists version 5.3a as the default version, so if you need to load the newest version 5.5, then you would use the VALET command ''vpkg_require comsol/5.5'' instead.

Templates for Slurm job submission scripts are available for batch COMSOL jobs in ''/opt/shared/templates/slurm/applications''.  Copy and edit the template based on your job by following the usage described in ''comsol.qs''.

<note tip>It is always a good idea to periodically check ''/opt/shared/templates/slurm/applications'' for changes in existing templates, or the addition of new templates, designed to provide the best performance for a particular version of COMSOL on that cluster.</note>