CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > OpenFOAM > OpenFOAM Installation

[foam-extend.org] Issue running on a Local 2-Workstation Cluster

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   October 23, 2020, 16:38
Question Issue running on a Local 2-Workstation Cluster
  #1
Member
 
Join Date: Nov 2015
Posts: 38
Rep Power: 10
WaterHammer1985 is on a distinguished road
Hello,


I have 2 workstations connected via ethernet cable and a password-less ssh. The computers talk to each other, ping between each, and I can run decomposePar on the master and the new directories are made on the slave. However, when I try to run a simulation (damBreak tutorial), nothing happens and the program appears to "hang". There is no error message given, just complete radio silence.



Any help on troubleshooting (or how to force an error message so i can know where to start) would be greatly appreciated. Pertinent (maybe) information is below:


1. Both workstations have foam-extend-4.1 installed in the same directory (~/opt/foam/foam-extend-4.1) on ubuntu 18.04. I've installed ssh and nfs-kernel-server. The only directory that The ssh is connected to a working directory that is the same on both ~/home/pc/runCluster.



2. The "machine" file lists the ip address of the master (1st line) and slave (2nd line).

3. If I add a bogus character to the machine file (ie X to the IP address), an error is returned. This makes me think that the problem is happening after the machine file is read.
WaterHammer1985 is offline   Reply With Quote

Old   October 27, 2020, 22:28
Default Update
  #2
Member
 
Join Date: Nov 2015
Posts: 38
Rep Power: 10
WaterHammer1985 is on a distinguished road
Update:
I have not figured out the solution to this issue, yet.

Recap:
1. Two computer setup
2. SSH and nfs-kernel-server
3. decomposePar runs successfully, the directories are created on both the master and slave
4. interFoam starts running but then hangs with no output and doesn't appear to "crash". I'm unable to force an error message output.
4a. interFoam run command: mpirun --hostfile machines /opt/foam/foam-extend-4.1/bin/foamExec interFoam -parallel > log 2>&1

Questions:
1. Is there a way to force an error message when the run hangs?
2. Suggestions on how to troubleshoot the problem?
WaterHammer1985 is offline   Reply With Quote

Old   October 27, 2020, 23:36
Default
  #3
Member
 
Fatih Ertinaz
Join Date: Feb 2011
Location: Istanbul
Posts: 64
Rep Power: 15
fertinaz is on a distinguished road
Hanging process probably indicates an MPI communication problem. You can add debugging directives in your controlDict to enable increased verbosity. I cannot remember what they're at the moment, but you can search that online.

However, I'd try the following steps first:
  • Prior to running OF, try a simple mpi ping-pong test to make sure that you can run an MPI application using both nodes.
  • Assuming that you're utilizing ethernet, set the following flag in your MPI command "--mca btl_tcp_if_include eth0".

Also, don't forget to source the OF environment on the compute node by default as well.

// Fatih
fertinaz is offline   Reply With Quote

Old   May 20, 2021, 03:08
Default
  #4
New Member
 
LancelotNeil
Join Date: May 2021
Posts: 1
Rep Power: 0
AbnerGodfrey is on a distinguished road
Select more lists, interesting categories other than radio station names, where do I search?
website internetradio a safe high quality option for users who want to listen to free radio stations.

Last edited by AbnerGodfrey; May 22, 2021 at 05:09.
AbnerGodfrey is offline   Reply With Quote

Old   May 18, 2023, 14:33
Default
  #5
New Member
 
David
Join Date: Sep 2021
Posts: 1
Rep Power: 0
Davrus is on a distinguished road
Water hammer, were you able to resolve this issue?
I appear to have the exact same scenario albeit running 2212 on Ubuntu 20.04.


Feels like an open mpi issue but I don't want to make assumptions. Same scenario as you in terms of host names.


Many thanks in advance,
David
Davrus is offline   Reply With Quote

Reply

Tags
cluster, foam-extend

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[solidMechanics] Support thread for "Solid Mechanics Solvers added to OpenFOAM Extend" bigphil OpenFOAM CC Toolkits for Fluid-Structure Interaction 686 December 22, 2022 09:10
Transient simulation not converging skabilan OpenFOAM Running, Solving & CFD 14 December 16, 2019 23:12
Floating point exception error lpz_michele OpenFOAM Running, Solving & CFD 53 October 19, 2015 02:50
Dual cpu workstation VS 2 node cluster single cpu workstation Verdi Hardware 18 September 2, 2013 03:09
pisoFoam with k-epsilon turb blows up - Some questions Heroic OpenFOAM Running, Solving & CFD 26 December 17, 2012 03:34


All times are GMT -4. The time now is 23:48.