Learning Forum

[rounaksingh]

Hi,

In our lab, all the computers have ANSYS electronics Desktop 19.2 with remote manager installed. We have four win10 (all same config, make, 64-bit i7 processors, 16GB RAM each) computers which we use to run individual remote simulations using Remote manager (1 to 1 remote simulation). It works perfectly. 

However, I would like to combine these four computers together as a cluster, and create a one of these computer to serve as a head node for the cluster. Then I would like to submit a simulation to head node to simulate HFSS simulations. Is these possible? I would greatly appreciate some instructions and help to guide me to create a cluster of four computers to share RAM and cores.

Thank you

[tsiriaks]

Hi rounaksingh,

You can do this but please note that there is no job scheduler integrated in AnsoftRSM or AEDT .

The first specified solving machine would be the 'point of contact' for any client machines but it wouldn't check the available resources on the 'compute nodes' and assign the jobs accordingly (since there is no job scheduler), also that first machine itself would be solving the job. This means that the client has to manually specify what machines to be used as computed nodes. You can have a situation where one machine is available but another machine has two jobs solving on it.

 

Now here is the steps to setup distributed solve on multiple machines.

 

1. Install same version of AEDT on each machine (make sure it's installed on the same path on all machines , or you can also install on one machine and use a shared directory. Note: This requirement is needed only if you are solving on multiple machines)

https://www.youtube.com/embed/nDYclZgt-Ts

 

2. Install AnsoftRSM on each solving machine

https://www.youtube.com/embed/OqOJ3W91sSU

 

3. Register AEDT with AnsoftRSM on each solving machine (if you are trying to setup multiple versions of AEDT, you have to register each of the version you want to setup)

This was part of the install AnsoftRSM video

 

 Note:  Steps 4-6 are for distributed solve on multiple machines only, if you just want to submit jobs to solve on a single machine, you can skip these steps.

 

4. Install IBM Platform MPI on each solving machine (Note: take all defaults during the installation). This is provided in the Electronics installation package.

 

 5. If you are setting up to solve on multiple machines but doesn't include the local machine as the solving machine, you must set this in AEDT GUI on the local machine: 

Make sure username/password is specified in Tools > options > general options > remote analysis

 

6. The temp directory on all solving machines must be the same path. We can set the path in (default) C:Program FilesAnsysEMAnsysEM1xxWin64configdefault.cfg  . You must select the path that is accessible by any user and on any solving machine, e.g.,  tempdirectory='C: /temp' . Note: even if it's windows, please use forward slash '/'

 

Hope this helps.

 

Thanks,

Win

 

 

 

[rounaksingh]

Hi Win,

Thanks for the response.

Do I have to give any username/password for IBM MPI. Is this username/password my windows password? Also, why there is a need for username/password? I am just curious.

Thanks

[tsiriaks]

Hi rounaksingh,

"Do I have to give any username/password for IBM MPI"

No, just use your Windows login credentials. IBM MPI doesn't require password caching. 

 

 "Is this username/password my windows password?"

Yes.

 

"why there is a need for username/password? "

If you solve on remote machines without specifying the local machine, the MPI processes will be launched by the AnsoftRSM service (which is installed and ran as SYSTEM user) on the first specified solving machine but the MPI cannot launch remote processes as SYSTEM user. It doesn't recognize the username SYSTEM so it fails. By using that setting it will launch the remote processes as the specific user. 

This also helps with being able to tie processes to users on shared machines.

On the other hand, if you include local machine, now the MPI process wouldn't be launched by AnsoftRSM service (SYSTEM user) but rather your own username because it's launched by the 'AEDT GUI' itself. So, this automatically be your own username.

Thanks,

Win

[rounaksingh]

Thanks Win!

[tsiriaks]

You are welcome !

Win

[mahesh2444]

nI would like to know how you configured the IBM MPI for successful simulations. I am having two pc's and I described my issue atn/forum/discussion/22480/facing-issues-while-setting-up-distributed-memory-simulations-in-ansys-edt-hfss-2020r1#latestnDo I need to do anything post installation of IBM MPI apart from the above mentioned things ? Do I need to register my credentials anywhere else for the mpirun to work ?nI have done the credential registration part as specified user in remote analysis available in AEDT GUI. nCan you please help me to get out of this problem ?nThanksnMaheshn

[mahesh2444]

Hello Array , ArraynAn update on my question. Among the two machines (DESKTOP-CLH2LM1-->(A), DESKTOP-B4I9FQ7-->(). nWhen I run the test with A as localhost and B as the other machine the MPI testing command results in Hello world! output indicating a good connection between A & B.nC:\Users\Mahesh>%MPI_ROOT%\bin\mpirun -pass -hostlist localhost:2,DESKTOP-B4I9FQ7:2 n%ANSYSEM_ROOT201%\schedulers\diagnostics\Utils\pcmpi_test.exenPassword for MPI runs:nmpirun: Drive is not a network mapped - using local drive.nHello world! I'm rank 0 of 4 running on DESKTOP-CLH2LM1nHello world! I'm rank 1 of 4 running on DESKTOP-CLH2LM1nHello world! I'm rank 2 of 4 running on DESKTOP-B4I9FQ7nHello world! I'm rank 3 of 4 running on DESKTOP-B4I9FQ7nBut when I tried to run the same MPI testing command with B as localhost and A as other machine, following output is obtained in command prompt window.nC:\Users\HP>%MPI_ROOT%\bin\mpirun -pass -hostlist localhost:2,DESKTOP-CLH2LM1:2n%ANSYSEM_ROOT201%\schedulers\diagnostics\Utils\pcmpi_test.exe                                                nPassword for MPI runs:                                                 nmpirun: Drive is not a network mapped - using local drive.                               nERR-Client: InitializeSecurityContext failed (0x80090308)                                nERR - Client Authorization of socket failed.                                      nCommand sent to service failed.                                             nmpirun: ERR: Error adding task to job (-1).                                       nmpirun: mpirun_mpid_start: thread 19792 exited with code -1                              nmpirun: mpirun_winstart: unable to start all mpid processes.                              nmpirun: Unable to contact remote service or mpid                                    nmpirun: An mpid process may still be running on DESKTOP-CLH2LM1  nI want to know why the output is like this and what settings do I have to make for getting same output as described earlier in this comment. nFor testing this distributed simulation feature I have started simulation of Helical_Antenna { available in examples (it is advised to consider this simulation as test case ANSYS 2020 R1 Help) } on Machine A. I have setup analysis configuration consisting of two machine with Machine B being the first one among the list followed by localhost. nBut the simulation steps like meshing and solving are only performed in Machine B and didn't used any of the hardware available in Machine A. Why this occurred ?nWhat settings do I need to modify for using both machines in the simulation ?nP.S: Machine A has Windows 10 Pro OS while Machine B has Windows 10 Home OS installed. Also there is one generation difference between processors on both machines. I have disabled the firewalls completely on both machines.nThanksnMaheshn