<html><head></head><body><div class="yahoo-style-wrap" style="font-family:Helvetica Neue, Helvetica, Arial, sans-serif;font-size:13px;"><div dir="ltr" data-setdir="false">Hi Mvapich team,</div><div dir="ltr" data-setdir="false"><br>I have a small compute cluster of 20 nodes,using mvapic2-2.2 on Inifiniband fabric, and there is only a single MPI process on each node. I am trying to debug a weird issue - occasionally, the slave node will get a stale/old message from the head node, instead of the actual message sent at that time. </div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Question : I would like to enable basic and verbose logging of MPI communication to help debug this issue. What option should I add to the 'mpirun_rsh' command line to get it ?.... and do the logs show up on the shell directly ? <br><br>I already tried adding <span style="font-family: "Times New Roman"; font-size: medium;">MV2_DEBUG_FORK_VERBOSE=1, but don't see any extra logs.</span></div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Appreciate a prompt response.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Thanks,</div><div dir="ltr" data-setdir="false">Sashi.B</div></div></body></html>