COMSOL Commands on Windows

Use a COMSOL command to start COMSOL products with detailed startup options.

The general syntax of the COMSOL commands is

<command> [<target>] [<options>] [<target arguments>]

where square brackets indicate optional arguments. There are several different commands (See <command> in the command syntax) that can be combined with optional targets to achieve various results. The table below lists the major available commands and targets (if the column is empty, the command is always available):

Table 22-1: COMSOL Commands and Targets
command and Target	Description	Availability
comsol	Run standalone COMSOL Desktop
comsolbatch	Run a COMSOL MPH-file or class file in batch mode
comsolcluster	Run COMSOL Desktop on a cluster	Requires a floating network license (FNL)
comsolclusterbatch	Run COMSOL cluster version in batch mode	Requires a floating network license (FNL)
comsolclustermphserver	Run COMSOL Multiphysics cluster server	Requires a floating network license (FNL)
comsolclusterxpl	Run cross-platform COMSOL Desktop on a cluster	Requires a floating network license (FNL)
comsolcompile	Compile a model file for Java or compile an application into an executable application (the latter option requires COMSOL Compiler)
comsoldoc	Launch the COMSOL Documentation window
comsolmphclient	Run COMSOL Multiphysics Client
comsolmphserver	Start COMSOL Multiphysics Server
comsolmphserver matlab	Start MATLAB® and connect to a COMSOL Multiphysics server	Requires a LiveLink™ for MATLAB® license
comsolpowerpointbatch	Update images in PowerPoint presentations
comsoltrust	Trust methods in add-ins
comsolxpl	Run cross-platform COMSOL Desktop

The commands are available in the bin\win64 subdirectory in the COMSOL installation directory. The COMSOL installer sets up a few of the possible commands on your Start menu and your desktop. In Windows 8, 8.1, and 10, you can click the shortcut on the Apps screen. This makes a folder with shortcuts to all COMSOL commands available.

To create additional customized commands, you can create shortcuts including all argument and put them on your desktop. You can also issue COMSOL commands in a command window. To conveniently access the command in a command window, you need to set up the Windows path to include the path bin\win64 in the COMSOL installation directory.

INI Files

For each launcher file, there is a corresponding .ini file in the same directory. It is sometimes recommended that these files are edited. For example, you can add options to any of the above commands by modifying the corresponding INI file. To change the option opt to value val, add the line

-Dopt = val

to the file comsol.ini. Change the file comsolbatch.ini for comsolbatch, and similarly for the other COMSOL targets.


	In general, for a system property or option, you add -D as a command option. For example, to set the system property cs.precmp to val, use the command option -Dcs.precmd = val.

Options

You can enter various options after the COMSOL command and target. Table 22-2 lists the options (See [<options>] in the command syntax) available for all COMSOL commands. Always issue these options between the command and the target (if any).

Table 22-2: COMSOL options (curly brackets indicate default values)
COMSOL option	Description
<target> -h	Print target-specific help.
-3drend ogl \| dx9 \| sw	3D renderer: OpenGL, DirectX, or software rendering.
-alloc native \| scalable	Memory allocator: Select from using the Windows® native memory allocator or the scalable memory allocator from the Intel® Threading Building Blocks library. COMSOL defaults to the scalable allocator for computers with more than 8 cores.3
-applicationsroot <path>	Specify custom path to the COMSOL Application Libraries root directory.1
-autosave {on} \| off	Control saving of recovery files.
-blas {auto} \| mkl \| blas \| path	BLAS library to use.4
-blaspath <path>	BLAS library path.4
-c <path>	License file path.
-ckl	Use class-kit license.
-clusterpartmethod {off}\|mo\|nd\|wnd	Cluster partitioning method. Choose from mesh ordering (mo), nested dissection (nd), or weighted nested dissection (wnd).
-clusterstorage all \| single \| shared	Cluster storage format. The single format does I/O only from the root node, while the shared format does I/O using distributed I/O operations. The shared format requires that all nodes have access to the same storage area and the same temporary storage area.
-comsolinifile <path>	Specify custom path to .ini-file used when starting COMSOL.
-configuration <path>	Path to directory for storing the state for the GUI between sessions and for performing different caching tasks. The configuration directory is by default a subdirectory to the preference directory. When running in batch or cluster mode, add @process.id to get a unique identifier to the path (for example, -configuration /tmp/comsol_@process.id).
-data	Path to a workspace directory for storing internal workspace information. The workspace directory is by default a subdirectory to the preference directory. The workspace directory is cleared when COMSOL is launched. When running in batch or cluster mode, add @process.id to get a unique identifier to the path (for example, -data /tmp/comsol_@process.id).
-docroot <path>	Specify custom path to the COMSOL documentation root directory.1
-h	Print general help.
-keeplicenses on \| {off}	Keep checked-out licenses when creating or opening an application.
-memoptassem {off} \| matrix \| vector \| on	Control of scalability assembling mode.
-migrateprefs {auto} \| on \| off	Migrate preferences from previous version.2
-mpmode throughput \| turnaround \| owner	Multiprocessor mode.3
-np <no. of cores>	Number of cores.3
-numafirst <numa number>	Set first NUMA node to bind process to.3
-numasets <no. of sets>	Number of NUMA sets.3 -numasets 1 represents the case where there is only one nonuniform memory access node — that is, the entire computer.
-prefsdir <path>	Preference directory.
-recoverydir <path>	Path to recovery directory. The recovery directory is by default a subdirectory to the preference directory.
-tmpdir <path>	Temporary file directory.
-v, -version	Print COMSOL version.
Reference
1 See Documentation and Application Libraries Root Directories. 2See Preference Migration 3See Shared-Memory Options. 4See BLAS Options.

For the -tmpdir option, the COMSOL Multiphysics software uses the specified directory to store temporary files. As an alternative, you can use the COMSOL_TMPDIR environment variable. Use the -prefsdir option to specify the directory where COMSOL Multiphysics stores the preference file.

Remote Desktop and Graphics Rendering

For a Floating Network License, you can access COMSOL Multiphysics with a Windows Remote Desktop connection. This way of accessing COMSOL Multiphysics is only supported with the software rendering graphics option.

Documentation and Application Libraries Root Directories

In a default COMSOL installation, the documentation files are located in the directory doc under the installation root directory. You can use the -docroot option if you want to move the documentation directory to a different location. Similarly, use the -applicationsroot option if you want to move the Application Libraries root directory applications from its default location under the COMSOL installation root. Relocating the documentation and Application Libraries root directories can be useful for administering an Application Library update; see The Application Library Update Window.


	Setting the paths to the documentation and Application Libraries root directories using these options does not in itself move the directories and their contents.

Preference Migration

By default, most preference settings are migrated from a previous COMSOL Multiphysics version when you start an instance of a new COMSOL Multiphysics version. To change this behavior, start COMSOL Multiphysics using

comsol.exe -migrateprefs on

to force a migration of preferences from the previous version and then overwrite the current preferences, or

comsol.exe -migrateprefs off

to not migrate any preferences.

Using the automatic preference migration, preferences are only migrated from the most recent previous version, they are only migrated on first launch, and the preference migration is only done once.

Some preferences for settings such as the root directories for documentation and application libraries are not migrated.

It is also possible to import and export preference settings using the dialog box in the COMSOL Desktop.

Shared-Memory Options

Use the option -np to control the number of cores used. The default is to use all available cores (processing units).

Use the option -numasets to control the number of nonuniform memory access (NUMA) node sets that the COMSOL Multiphysics software should take into account. This is usually the number of processor sockets that the hardware is using. Note that -numasets 1 represents the case where there is only one nonuniform memory access node — that is, the entire computer. If you only set the -np option, the number of sockets is determined automatically so that sufficient number of sockets are used by default. The -np flag, together with the -numasets flag, decides the size of a NUMA set (that is, -np divided by -numasets). The purpose of -numafirst is to decide which processor core number to place the first NUMA set on (that is, the size of the NUMA set times numafirst).

Depending on how loaded the machine is, you can control how COMSOL Multiphysics uses the available processors with the -mpmode option. The following options are available:

Table 22-3: COMSOL Multiprocessor Mode Options
MPMODE Option	Description
owner	Provides the highest performance in most cases.
throughput	Is expected to give the best performance when several different processes are running actively at the same time as COMSOL Multiphysics.
turnaround	Typically provides the best performance when no other processes than COMSOL Multiphysics are active.

Use the option -alloc to specify memory allocator type. The default is to use the native memory allocator for computers with less than eight cores and otherwise the scalable memory allocator. The scalable memory allocator can increase performance significantly for computers with many cores but uses more memory.


	You can also specify the number of cores and sockets and the use of the scalable allocators as preferences on the Multicore and Cluster Computing page in the Preferences dialog box. To specify those numbers manually, select the Number of cores and Number of sockets check boxes to enter a number in the associated text fields. By default, all cores are used and the number of sockets are set automatically. If you lower the number of cores, it is good practice to also lower the number of sockets. The preference option for the scalable allocator is called Optimized for multicore. If you want to choose another memory allocator than the default setting, select the Memory allocator check box and the choose Native or Optimized for multicore. To control the scalability assembling mode, which can be useful even when running on a single node, select the Memory scalability optimization for assembling check box. You can then select Off (the default, for no scalability mode), Matrix for activating scalability mode only for matrix assembling, Vector for activating scalability mode only for vector assembling, or All for activating scalability mode for all cases. You can also control these options with a command-line argument -memoptassem.

BLAS Options

BLAS is a set of functions for basic linear algebra operations. A large portion of the computational engine in the COMSOL software relies on BLAS. The COMSOL software provides for the following BLAS-related options:

Table 22-4: COMSOL BLAS Options
BLAS Option	Description
auto	The default option is to use the Intel MKL library.
mkl	Use the Intel MKL library (included with installation).
blas	Use the standard BLAS library (included with installation).
path	Use a BLAS library specified using the option -blaspath or the environment variable COMSOL_BLAS_PATH.

Both MKL and BLAS are distributed with COMSOL Multiphysics.

If you want to use a different BLAS library than the ones provided by COMSOL, make sure that COMSOL Multiphysics can find the library. The simplest way for COMSOL Multiphysics to find a library is to put it in /lib/win64 or somewhere in the standard search path. Also provide the path to any sublibraries needed by the library. Set the search path to point to the directory where the library is installed. To do so, use the environment variable PATH. Your library must support both the standard FORTRAN LAPACK interface and the standard FORTRAN BLAS interface. If your LAPACK and BLAS interface consists of several libraries, use the path to the LAPACK library.

Application Options

The following options are used to specify inputs to an application with command-line options.Find more information about these options in the section The Application Argument Node in the Application Builder Reference Manual.

Table 22-5: COMSOL Target command-line arguments
COMSOL Applications Options	Description
-appargnames <names>	Comma-separated list of argument names.
-appargvalues <values>	Comma-separated list of argument values.
-appargsfile <filename>	A file with arguments to the application. Each line in the file should have the format <name>=<value>.
-appargvarlist <names>	Comma-separated list of argument names whose values are on file.
-appargfilelist <filenames>	Comma-separated list of file names. Each file contains the value for one argument.

COMSOL Commands for Applications

In additions to the options in Table 22-2, the standalone COMSOL command supports the following options on Windows:

Table 22-6: COMSOL command-line arguments
COMSOL Options	Description
-edit <file>	Edit application.
-open <file>	Open application.
-run <file>	Run application.

For example, use comsol -open myapp.mph to open an application. Applications can be run or edited with the two other options.

Changing The Background Color of the Graphics Window

To change the default blue color scheme for the background of the 3D Graphics window, you can start the COMSOL Multiphysics software with the following command-line option:

-Dcs.canvascolor=255,0,0,0,255,0

In this example, the background becomes red and green. The first three numbers are the RGB (red, green, blue) values for the top color, and the last three numbers are the RGB values for the bottom color, with interpolated hues between those two colors. All numbers are between 0 and 255 (inclusive). This option is also available when running COMSOL Multiphysics on Linux and Macintosh.

COMSOL Multiphysics Server Commands

Use a COMSOL Multiphysics server command to start a COMSOL process ready to process computational requests. A COMSOL Multiphysics server listens for TCP/IP connections from COMSOL Multiphysics clients. A COMSOL Desktop can become a COMSOL Multiphysics client by connecting to a COMSOL Multiphysics server. The LiveLink™ for MATLAB® also needs to connect to a COMSOL Multiphysics server.

The Windows syntax for the COMSOL Multiphysics server command is

comsolmphserver [<options>] [<target arguments>]

The following target arguments are available for a COMSOL Multiphysics server command:

Table 22-7: COMSOL Multiphysics Server Target command-line arguments
COMSOL Multiphysics Server Option	Description
-graphics	Start the server with graphics libraries. This displays plots on the server when you are connected with a client (that is, not with the COMSOL GUI).
-ipv6	Make COMSOL Multiphysics server listen on an IPv6 port.
-login {info} \| force \| never \| auto	Ask for login information. info means that only missing information is asked for. force resets the password. never requires that the login information is available. auto automatically creates a new username and password.
-multi {auto} \| on \| off	Accept repeated client connections.
-passwd reset \| nostore	Specify that you want to provide a new password. To avoid storing the new password on file, use nostore.
-port <port>	Specify a TCP/IP port, <port>, to listen for attempts to connect. The <port> is the server port, or 0 for a random free port.
-portfile <path>	Specify that COMSOL Multiphysics writes its server port to the given <path> when it has started listening.
-silent	Do not listen to standard input.
-user <user>	Specify login name for a user.

Accessing the COMSOL Multiphysics Server Computer

The server computer can be accessed in several ways. You can log in to a machine that is dedicated to a single person. You can also connect to the server computer by using Remote Desktop. Start the COMSOL Multiphysics server from the menu. If several people want to access a single Windows computer to run the COMSOL Multiphysics server, you must use Windows Terminal Server or another tool that allows multiple users to log in on the same Windows server. In some Windows versions, Microsoft® provides a Telnet Server with which you can log in through a terminal window. When using a terminal window to log in on Windows, use the comsolmphserver command to start the COMSOL Multiphysics server.

When a COMSOL Multiphysics server is started for the first time, you are asked for a username and password. Select a username and a password, which COMSOL Multiphysics then uses in communications between the COMSOL Multiphysics client and the server. You must also specify a matching username and password in the dialog box. The software writes this login information in the subdirectory .comsol/v60/login.properties in your Windows home directory.

Client/Server Security Issues

COMSOL Multiphysics can operate in a client/server mode where COMSOL Multiphysics runs as a separate client and a server. COMSOL uses a TCP/IP connection to send data between the server and the client.


	Always make sure that untrusted users cannot access the COMSOL login information. Protect the file .comsol/v60/login.properties in your home directory. This is important when running COMSOL Multiphysics in client/server mode. Alternatively, start the COMSOL Multiphysics server with the -passwd nostore option, and clear the Remember username and password check box when connecting to the server. This ensures that your login information is not stored on file.

Once a COMSOL Multiphysics server is started, a person with access to your login information could potentially connect to your COMSOL Multiphysics server. When a COMSOL Multiphysics client connects or disconnects from a remote computer, the COMSOL Multiphysics server displays a message. The connection from the client to the server is made with the TCP protocol.

The server and client are mutually authenticated using a challenge handshake authentication protocol, which means that login information cannot be easily obtained by someone eavesdropping on the network communication. The TCP connection between the client and the server is otherwise not encrypted. If you require encryption of the TCP connection, you can use third-party software based on protocols such as SSH or IPSEC.

To enhance security, you can limit the address range that can access the COMSOL Multiphysics server, both in your firewall and by changing the COMSOL Multiphysics server configuration. To limit the allowed address range in the server, edit the file <COMSOL Installation Directory>\bin\tomcat\conf\server.xml and find the lines:

<!-- To restrict access to the COMSOL server you can uncomment the block below.

and follow the instructions. The default port for the COMSOL Multiphysics server is 2036. You can change this by using the option -port <port> when launching COMSOL and COMSOL Multiphysics server.

Documentation Security Issues

To serve the COMSOL Desktop with documentation, COMSOL opens a separate documentation server on the client computer when you open the documentation.

To enhance security, you can limit the address range that can access the documentation server, both in your firewall and by changing the documentation server configuration. To limit the allowed address range in the server, edit the file <COMSOL Installation Directory>\doc\help\conf\server.xml and find the lines:

<!-- To restrict access to the documentation server you can uncomment the block below.

and follow the instructions. The default port for the documentation server is 8090. You can change this by using the option -docport <docport> when launching COMSOL Multiphysics.

COMSOL Multiphysics Client Commands

Use a COMSOL Multiphysics client command to start a COMSOL Desktop with a the Connect to Server dialog box open.

The syntax for the COMSOL Multiphysics client command is

comsolmphclient [<options>] [<target arguments>]

The following target arguments are available for a COMSOL Multiphysics client command:

Table 22-8: COMSOL Target command-line arguments
COMSOL Multiphysics Client Options	Description
-open <file>	Open file
-port <port>	Specify a TCP/IP port to connect to
-server <server name>	Specify server to connect to

COMSOL Batch Commands

Use the COMSOL batch command to run COMSOL jobs without a user interface. Run both Model MPH-files and model files for Java with the COMSOL batch command. Model files for Java need to be compiled before running.

The Windows syntax for the COMSOL batch command is

comsolbatch [<options>] [<target arguments>]

Its detailed target arguments are:

Table 22-9: COMSOL BATCH-specific arguments
COMSOL Batch Target Arguments	Description
-alivetime <seconds>	The time between writing status on disc.
-batchlog <filename>	File to store log in. If not used, the log appears in the command window.
-batchlogout	Log to standard out when storing on file.
-cancel	Stop the current solver without returning any data. See below.
-checklicense <filename>	Print license requirements for a Model MPH-file.
-classpathadd <classpath>	Additional classpath.
-clearmesh	Clear all meshes,
-clearsolution	Clear all solutions (except probe data),
-client	Run as client.
-continue	Continue computing an interrupted batch job.
-dev <filename>	Path to a JAR-file with additional classes to call from the batch class file.
-error {on} \| off	Stop if an error occurs. This argument is only applicable when -plist and -pname represent multiple parameter tuples. It is otherwise ignored.
-graphics	Start COMSOL batch with graphics libraries. This displays plots during analysis.
-host	Connect to host.
-inputfile <filename>	Run a Model MPH-file or class file.
-job <job tag>	The batch job to run. See The Job Option below.
-jobfile <filename>	Specify a text file using the following format: <inputfile0> <outputfile0> <inputfile1> <outputfile1> <inputfile2> <outputfile2> … If the filename <inputfile0> or <outputfile0> contains spaces, surround the path by double quotation marks ("..."). Each input-output pair will be run as a batch job consecutively. Other batch-specific options specified at the command line are applied to each of the listed jobs. In addition, the list can be updated continuously during the batch process.
-methodcall <tag> -inputfile <filename>	Run a method call with the given tag. The file in <filename> contains the method call. See the documentation for model.methodCall() in the COMSOL Multiphysics Programming Reference Manual for additional input arguments that can be used from batch commands with -methodcall for passing input values as arguments to a method call.
-mode {batch} \| desktop	Ignore Batch and Cluster Computing settings. See Ignoring Batch and Cluster Computing Settings below.
-norun	Do not compute the model. This option is useful if you, for example, just want to run -clearsolution or -clearmesh on a model that already includes a solution or mesh and then save it, without a solution or mesh, without computing the model first.
-nosave	Do not save the resulting model.
-outputfile <filename>	Save a Model MPH-file using the given filename. If output is not given, the input file is overwritten with the output.
-paramfile <filename>	Table file containing parameter names in the first row and corresponding parameter value tuples in the following rows. That is, the parameter names should be on the first row (space separated), and the parameter values (if only one tuple) should be space separated on the second row. If you want to solve for more tuples, more rows are added in the same manner.
-pindex <parameter indices>	Comma-separated list of parameter indices (integers). The number of indices given has to correspond to the number of arguments given by -plist.
-plist <parameter value>	Comma-separated list of parameter values. For information about providing parameters using argument, see About Providing Parameters below.
-pname <parameter name>	Comma-separated list of parameter names. For information about providing parameters using argument, see About Providing Parameters below.
-port	Connect to port.
-prodargs	Add extra command-line arguments using -prodargs followed by the arguments last in the call to COMSOL batch.
-recover	Recover and continue computation. See The Recover Option below.
-resethistory	Compact the history before saving. This argument can be useful, together with -clearmesh and -clearsolution, to reduce the size of the saved file.
-stop	Stop the current solver when it has finished, returning available data. See below.
-stoptime <time to stop>	Stop the batch job after a certain time (in seconds).
-study <study tag>	The study to compute. See The Study Option below.
-usebatchlic	Use batch license (requires batch licenses). See The Usebatchlic Option below.

Stopping and Canceling a Batch Job

You can stop a batch job using the following command:

comsolbatch -stop <level> -inputfile <filename>

where <level> is the level to stop the process on. Set the level to a high value in order to stop as soon as possible. By default, it is set to 100. The -inputfile option indicates the filename of the model that another process is running. The inputfile arguments should be consistent with the one specified to launch another process. That is, either the same inputfile arguments should be provided or the -inputfile should be the same as the -outputfile specified to launch another process.

You can cancel a batch job using the following command:

comsolbatch -cancel -inputfile <filename>

The -inputfile option indicates the filename of the model that another process is running. The inputfile arguments should be consistent with the one specified to launch another process. That is, either the same inputfile arguments should be provided or the -inputfile should be the same as the -outputfile specified to launch another process.

Example

To use the COMSOL Batch mode to solve a model, run the following command:

comsolbatch -inputfile in.mph -outputfile out.mph -study std1

This command starts COMSOL Batch, solves the model in the Model MPH-file with the given filename (in.mph in this example) using the active solver settings in the model, and stores the solution in the out.mph. You can also use multiple sets of input files and output files, stored in a file using the -jobfile option.

The Study Option

The -study option directs COMSOL Multiphysics to run a certain study. The study is identified by its tag. In the COMSOL Desktop, select under to see the tags of the jobs under within curly braces in the Model Builder. In the model object, determine the tags of the jobs by the command model.study().tags(). You can determine the name of each study by model.study(<tag>).name() using one of the job tags.

The Job Option

The -job option works similar to the -study option. It directs COMSOL Multiphysics to start a certain job. The job is identified by its tag. In the model object, determine the tags of the jobs by the command model.batch().tags(). You can determine the name of each job by model.batch(<tag>).name() using one of the job tags.

The Usebatchlic Option

The -usebatchlic option makes COMSOL use batch licenses for the job. This option is equivalent to the check box available in the and study nodes. For floating network licenses (FNL), a separate set of batch features are available for COMSOL Multiphysics and the licensed add-on products. Using batch licenses for a cluster computing or cluster sweep job means that you can continue working in the COMSOL Desktop locally while running batch jobs on remote computers and clusters using only a single FNL license.

The Recover Option

For the -recover option, the working directory (where all .log, and .status files are generated) will contain the recovery file, which contains information about the recovery folder in the case that the COMSOL software stops working. If the -recover option is specified, the model from the recovery directory will be opened. If opening that model succeeds, a continue operation will be performed; otherwise, the input filename model will be simulated.

Ignoring Batch and Cluster Computing Settings

When -mode is batch (the default), all Batch and Cluster Computing settings are ignored: that is, Batch and Cluster Computing features will not start any batch jobs as they will do when you click in the COMSOL Desktop.

When -mode is desktop, Batch and Cluster Computing settings will be used. This case corresponds to clicking in the COMSOL Desktop. All paths in the and nodes must correspond to paths that you would set up in the COMSOL Desktop if you started it and clicked instead of running the COMSOL batch command.

About Providing Parameters

You can provide parameters as parameter names and corresponding values using the -pname and -plist arguments, respectively. For example, -pname a,b -plist 1,2 corresponds to

model.param().set("a",1);

model.param().set("b",2);

which means that any global parameters with the same names are overwritten by these new values. The model will then use these new values. Also note that the model is saved with a new name that contains the parameter tuple. Parametric sweeps will work as if you set the global parameters a to 1 and b to 2 and then compute a parametric sweep. Multiple tuples (such as -plist 1,2,3,4) will be saved in multiple files.

The COMSOL Batch Commands for Updating Images in PowerPoint Presentations

The comsolpowerpointbatch command updates linked images in PowerPoint® presentations. The command is available on Windows only, and it requires that PowerPoint is installed. The command syntax is

comsolpowerpointbatch [<options>] [<target arguments>]

The following optional target arguments are available:

Table 22-10: COMSOLPowerPointbatch arguments for updating images in presentations
COMSOLPowerPointBatch Arguments	Description
-update <path1;path2;path3>	Required. Specifies the PowerPoint files, or folders to update. If multiple inputs are specified each input is separated using semicolon. An input path can be file path (ends with .pptx), or a folder path. If an input path is a folder path, all files ending with .pptx will be added as files to update. Only PowerPoint presentations with the file ending .pptx can be updated with the batch update.
-outputfolder <folder path>	Required. Specifies the folder where the updated PowerPoint files should be saved.
-help	Display the help for the command.
-h	Display the help for the command.
-batchlog <filename>	Optional. File to store the log in. If not used, the log appears in the command window. The log file is saved as plain text. The filename can be specified with or without a file extension. Allowed file extensions are: .log, .txt, and .text.
-applications <path1;path2;path3>	Optional. Provides a list of paths for overriding the paths saved in the PowerPoint presentations. All the model paths in the PowerPoint presentations that have the same short name as provided by -applicationnames will be overruled by the provided paths. If the -applicationnames argument is not used the short names are considered to be the file names, without the file extension as given by -applications. Each provided path must be a .mph file path.
-applicationnames <shortName1,shortName2,shortName3>	Optional. Can only be used if the -applications argument is also used, and must then match the number of paths provided by the -applications argument. Provides a list of model short names for overriding the paths saved in the PowerPoint presentations. All stored model paths that have the same short name as in the provided list will be overruled with the corresponding path given by -applications.
-applicationsfile <path>	Optional. Provides a file containing short names and paths for remapping applications. Each remapped application is specified in a single line and where the short name and the path is separated by an equal sign.
-applicationsroot <path>	Optional. This argument overrules the -applications, and -applicationsfile arguments. The specified path replaces the root part of the stored application paths in the presentations. This is done by replacing different parts of the model paths until a match is found.
-applicationpaths <path1;path2;path3>	Optional. Provides a list of additional folders where to look for the .mph files. If multiple folders are specified each folder is separated using semicolon.
-onlysavemphname	Optional. When used only the .mph file name, without the folder path, will be saved in the updated PowerPoint presentation.

The COMSOL Compile Command

The comsolcompile command compiles a model file for Java for use by the COMSOL batch command or for loading class files into the GUI. With the COMSOL Compiler, you can also use it to compile COMSOL applications into standalone executable applications. The Windows syntax for the COMSOL compile command is

comsolcompile [<options>] [<target arguments>] <file>.java

The Java file is mandatory. The following optional target arguments are available:

Table 22-11: COMSOL compile arguments for Compiling Java-Files
COMSOL compile Target Arguments	Description
-classpathadd <classpath>	Additional classpath.
-jdkroot <path>	Path to the JDK root.
-verbose	Verbose output.

To compile an application in an MPH-file into a standalone executable application using COMSOL Compiler, use

comsolcompile <full path to MPH-file> [<compile arguments>]


	Compiling applications requires a license for COMSOL Compiler™.

The following arguments are available:

Table 22-12: COMSOL compile arguments for Compiling Applications
COMSOL compile Arguments	Description
-iconmacos <path>	Path to image file for application icon on macOS.
-iconwindows <path>	Path to image file for application icon on Windows.
-outputdir <path>	Specify where the compiled application should be saved. The default is the directory where the application’s MPH-file is located.
-phbarchive <path>	Path to an external physics archive (folder or .jar file).
-platforms windows,linux,macos	The platforms to compile for. Specify as a comma-separated list. The default is the platform where the compiler is run.
-runtimetype {download} \| embed	The type of runtime to include when compiling.
-splash <path>	Path to image file for splash screen.

Options not given are taken from the application’s node, except for -outputdir and -platforms.

COMSOL Cluster Commands

All COMSOL cluster commands require a floating network license.


	See also Overview of Simulations on Shared- and Distributed-Memory Computers.

To start a COMSOL Desktop running in distributed mode interactively on a Windows cluster, type

mpiexec -n <number of nodes> comsolcluster.exe <options> [<target arguments>]

To start a COMSOL Multiphysics server running in distributed mode, for interactive use from a COMSOL Multiphysics client, on a Windows cluster, type

mpiexec -n 1 comsolmphserver.exe [<options>] <target arguments>] -cluster on : -n <number of nodes-1> comsolclustermphserver.exe <options> [<target arguments>]

Note that all options and target arguments need to be repeated twice, when using the above command.

To start a cross-platform COMSOL Desktop running in distributed mode interactively on a Windows cluster, type

mpiexec -n <number of nodes> comsolclusterxpl.exe <options> [<target arguments>]

To start a COMSOL batch command running in distributed mode on a Windows cluster, type

mpiexec -n <number of nodes> comsolclusterbatch.exe <options> [<target arguments>]

The following cluster commands are available:

Table 22-13: COMSOL Cluster Targets
COMSOL cluster commands	Description
comsolcluster	Run COMSOL Desktop in distributed mode interactively on a cluster
comsolclusterbatch	Run a COMSOL batch job on a cluster in distributed mode
comsolclustermphserver	Helper command to run COMSOL Multiphysics server on a cluster
comsolclusterxpl	Run the cross-platform COMSOL Desktop in distributed mode interactively on a cluster
comsolmphserver -cluster on	Run a COMSOL Multiphysics server in distributed mode, for interactive use from COMSOL Multiphysics client

The preferred way of starting COMSOL jobs is from the Job Configurations node in the COMSOL Desktop’s model tree.


	Micromixer — Cluster Version: Application Library path COMSOL_Multiphysics/Cluster_and_Batch_Tutorials/micromixer_cluster

If you need to start COMSOL cluster jobs from the command line, the preferred way is to use the comsolclusterbatch command because the comsolclustermphserver and comsolcluster commands require TCP/IP access from your client computer to the cluster node where COMSOL Multiphysics runs.

The Windows Configuration

•

Make sure that Windows HPC Server 2008, Windows Server 2012 with HPC Pack 2012, or Windows Server 2016 with HPC Pack 2016 job scheduler is installed. Running distributed COMSOL on other Windows versions is not supported.

•

Make sure that the Windows HPC Server working directory is set to point to the comsol command directory (<path to COMSOL install directory>
\bin\win64). The install directory must be shared between the nodes on your cluster. In some network configurations, the firewall prevents you from starting MPI on a shared executable. To register the executable with the firewall, use the clusrun command to execute the hpcfwutil command on all nodes (for instance, to register comsolclusterbatch) use clusrun /all hpcfwutil register comsolclusterbatch.exe <shared path to COMSOL install directory>\bin\win64\comsolclusterbatch.exe

•

You need to install Microsoft Visual Studio® runtime libraries on each compute node. You can install them from the \ext directory of the DVD using the clusrun command, for instance. (See https://www.comsol.com/support/knowledgebase/1083.)

•

Also make sure that all nodes that you intend to run COMSOL Multiphysics on have access to the license manager and that you can start COMSOL Multiphysics running in nondistributed mode. The nodes require access to the license manager to check out licenses.

•

Make sure you have installed the latest version of Microsoft MPI that is supported by your Windows version. Download and install the latest supported version of Microsoft MPI from Microsoft on your cluster nodes.

Using Microsoft MPI and SMPD on Standalone Computers

If you do not have Windows HPC Server installed on your Windows computers, you can still use the COMSOL cluster commands if you install COMSOL and Microsoft MPI on each computer that you want to use in the cluster. On each computer, you must then run the command

smpd

which is located in the Microsoft MPI installation subfolder Bin, as the user that will run the MPI job. You can then start the distributed mode by replacing the previous mpiexec -n <number of nodes> syntax with

mpiexec -hosts <number of nodes> <list of computer names> …

Here the mpiexec command is located in the same folder as smpd, and the local node should be listed first in the list of computer names if you want to run interactively. To start COMSOL Desktop in distributed mode, use the syntax

mpiexec -hosts <number of nodes> <list of computer names> comsolcluster.exe <options> [<target arguments>]

Example of the COMSOL Batch Command

Schedule a job with the command

mpiexec -n -1 comsolclusterbatch.exe -np 2 -inputfile <filename>

to run a COMSOL batch job on a number of computational nodes given by mpiexec. For further information about the mpiexec command and Windows HPC Server, consult the documentation that was shipped with the product and the online manuals.

Example of the COMSOL Multiphysics Server Command

When a COMSOL Multiphysics server cluster job is created, a preference directory must be set and be reachable from all nodes to avoid problems with the server login; see The COMSOL Commands and Login Information. The preferences can be generated by starting COMSOL Multiphysics server once on the head node using the following command:

comsolmphserver.exe -prefsdir <prefsdir>

where <prefsdir> is a preference directory common to all nodes.

When the COMSOL Multiphysics server is started on the cluster, the port number is written to standard output, so a standard output file and a standard error file must be set for the cluster job. To start a COMSOL Multiphysics server, schedule a job with the following command:

mpiexec -n 1 comsolmphserver.exe -np 2 -prefsdir <prefsdir> -cluster on :
-n <number of nodes-1> comsolclustermphserver.exe -np 2 -prefsdir <prefsdir>

You must be able to access the cluster node where the COMSOL Multiphysics server runs from the COMSOL Multiphysics client computer.

COMSOL MPI Options

The COMSOL cluster target arguments specify what MPI library to use and what Scalapack version to use. There are several implementations of MPI. COMSOL by default uses the Windows HPC Server libraries. The COMSOL software also supports most MPI implementations based on MPICH2. It is recommended that the default library is used. In addition, the COMSOL software includes a compatibility mode, which you activate by adding the option -mpi mpich2. When using this option, both the variables PATH and LD_LIBRARY_PATH must include the MPI implementation. It is also possible to use other MPI libraries based on MPICH2 using the option -mpipath <path to shared library>. The following options are available for COMSOL cluster commands:

Table 22-14: COMSOL Cluster Options
COMSOL Cluster Options	Description
-mpi {auto} \| mpich2 \| whpc2008 \| user \| path	MPI library to use
-mpiio {on} \| off	Set the MPI I/O mode. Setting this property to off means that COMSOL doesn’t search for a distributed file system.
-mpipath <file>	MPI shared library file.1
-scalapack {auto} \| mpich2 \| whpc2008 \| user \| path	Scalapack library to use.
-scalapackpath <path>	Scalapack library path.

The Cluster Computing study allows you to set up a batch job for submission to a Windows HPC Server job scheduler. There are several settings that you can configure in the comsol.ini file to get default settings:

-Dcs.scheduler=<IP or network address>

-Dcs.clusteruser=<Username on cluster>

-Dcs.rundir=<Where the model file is located on the cluster>

-Dcs.comsoldir=<Installation path to comsol on the cluster>

Additionally you can configure the following commands to get default settings:

-Dcs.precmd=<Command line>

-Dcs.postcmd=<Command line>

These two lines add commands prior to the comsol command and after the comsol command, respectively. You can add {nn} or {perhost} to any of these pre- and postcommands, which configures the Cluster Computing study to use the number of nodes and number of nodes on each host from the corresponding settings for the Cluster Computing study. For more information, see Cluster Computing.

COMSOL MATLAB Command

Use the COMSOL matlab command to access the COMSOL API through MATLAB. Enter the following command:

comsolmphserver matlab

which launches a COMSOL Multiphysics server in a console window, starts MATLAB, and connects MATLAB to the COMSOL Multiphysics server.

The following options are available for the comsolmphserver matlab command:

Table 22-15: COMSOL MATLAB options
COMSOL MATLAB options	Description
-desktop	Start with Desktop.
-graphics	Start the server with graphics libraries. This enables plotting on the server. Available only when running comsolmphserver matlab [<options>].
-host <hostname>	Connect to host.
-mlnosplash	Start without MATLAB splash screen.
-mlroot <path>	MATLAB installation directory.
-mlstartdir <path>	Start in directory path <path>
-nodesktop	Start without Desktop.
-port <hostname>	Connect to port.

The comsoltrust Command

Use the comsoltrust command to trust methods used in add-ins. The following commands are supported:

•

comsoltrust list, to list the content of the trust store (all trusted add-in methods).

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comsoltrust add -addinfile <path_to_addin> [-addinmethods <method_name1> [, method_name2, ...], to trust the listed methods for an add-in as a comma-separated list. If no methods are give, all methods in the add-in are trusted. A TrustID is created for the trusted methods

•

comsoltrust revoke <TrustID>, to revoke the privilege from an add-in method. You can see the TrustID in the list view.