Cool! I dimly remember this project; it was written independently of the main Open MPI project.
It looks like it supports the TCP OOB and TCP BTL. The TCP OOB has since moved from Open MPI's "ORTE" sub-project to the independent PRRTE project. Regardless, TCP OOB traffic is effectively about the control plane -- it's management messages, setup, teardown, stdout/err redirection, ... etc. Depending on the goals of the Open MPI wireshark plugin, it may or may not be worth it to dissect that traffic. The TCP BTL is the actual MPI messages that are sent across TCP (assuming you don't have some kind of HPC-class networking stack, that likely uses OS-bypass and probably doesn't use TCP). Keep in mind that neither of these plugins have ever formally published a wire protocol, and are therefore subject to change at any time. That's a not-insignificant risk for having an mpi-dissector plugin. ________________________________ From: users <users-boun...@lists.open-mpi.org> on behalf of Belanger, Martin via users <users@lists.open-mpi.org> Sent: Monday, December 11, 2023 10:55 AM To: users@lists.open-mpi.org <users@lists.open-mpi.org> Cc: Belanger, Martin <martin.belan...@dell.com>; jul...@rilli.eu <jul...@rilli.eu> Subject: [OMPI users] MPI Wireshark Packet Dissector I’m new to MPI and I needed to analyze MPI packets with Wireshark. I found Julian Rilli’s “mpi-dissector” project on GitHub (https://github.com/juhulian/mpi-dissector). The project is about 9 years old and does not compile with the latest Wireshark code. Fortunately, I was able to port it, build it, and make it work. It is not clear which version of the MPI protocol this project supports. Suffice it to say that since the code is 9 years old, it probably does not support all of the MPI protocol changes/additions made in the last 9 years. I wanted to share this with the Open-MPI community in case someone is interested and would like to update the code to support the latest version of MPI (I don’t know enough about MPI to do this work myself). Eventually, I will submit this to the Wireshark project so that it can be part of Wireshark going forward. For anyone interested, the ported code can be found in my fork of the Wireshark repo: https://gitlab.com/martin-belanger/wireshark/-/tree/mpi-support-v1?ref_type=heads. It can be cloned as follows: git clone -b mpi-support-v1 https://gitlab.com/martin-belanger/wireshark.git Regards, Martin Belanger
