Cardinal

STAR-CCM+ MPI job failure and workaround

STAR-CCM+ encounters errors when running MPI jobs with Intel MPI or OpenMPI, displaying the following message:

ib_iface.c:1139 UCX ERROR Invalid active_speed on mlx5_0:1: 128

This issue occurs because the UCX library (v1.8) bundled with STAR-CCM+ only supports Mellanox InfiniBand EDR, while Mellanox InfiniBand NDR is used on Cardinal. As a result, STAR-CCM+ fails to correctly communicate over the newer fabric.

Affected versions

18.18.06.006, 19.04.009 and possibly later versions