Hi Martin, Could you try the latest version https://www.mpich.org/downloads/ ? -- Hui Zhou From: Martin Ivanov via discuss <[email protected]> Reply-To: "[email protected]" <[email protected]> Date: Thursday, May 7, 2020 at 11:35 AM To: "[email protected]" <[email protected]> Cc: Martin Ivanov <[email protected]> Subject: [mpich-discuss] Run mpich on localhost Hello, I installed mpich-3.0.4 on a x86_64 BSD machine. I need to run MPI on this single machine, which has 8 cores. When I run the cpi example, I get: marto@% mpiexec -n 3 mpich-3.0.4/examples/cpi ssh: Could not resolve hostname : hostname nor servname provided, or not known If I make a hosts file with a single line content like this: marto@% cat hosts localhost:3 and again try the cpi example, I get: marto@% mpiexec -f hosts -n 3 mpich-3.0.4/examples/cpi [mpiexec@] HYD_pmcd_pmiserv_proxy_init_cb (./pm/pmiserv/pmiserv_cb.c:517): assert (!closed) failed [mpiexec@] HYDT_dmxu_poll_wait_for_event (./tools/demux/demux_poll.c:77): callback returned error status [mpiexec@] HYD_pmci_wait_for_completion (./pm/pmiserv/pmiserv_pmci.c:197): error waiting for event [mpiexec@] main (./ui/mpich/mpiexec.c:331): process manager error waiting for completion Any suggestions will be appreciated. Best regards, Martin