I have set "btl_tcp_if_include = ib0" in ~/.openmpi/mca-params.conf. When I run mpirun without podman, it runs right. When I run mpirun with podman, the "btl_tcp_if_include = ib0" is invalid. But when I add "--mca btl_tcp_if_include ib0" to command line, it is valid. $ mpirun -np 128 --hostfile mfile --mca btl_vader_single_copy_mechanism 3 --mca orte_tmpdir_base /tmp/podman-mpirun podman run --env-host --env-file envfile --userns=keep-id --network=host --pid=host --ipc=host -v /tmp/podman-mpirun:/tmp/podman-mpirun:z -v ./bulk:/bulk -w /bulk 4756bc6d2be0 vasp_std running on 128 total cores [ga2211][[19883,1],64][btl_tcp_endpoint.c:626:mca_btl_tcp_endpoint_recv_connect_ack] received unexpected process identifier [[19883,1],88] ... ... Here is hang. ... ... VASP version: vasp.5.4.4.18Apr17-6-g9f103f2a3. OpenMPI version: 4.1.1 $ podman version Client: Podman Engine Version: 4.0.2 API Version: 4.0.2 Go Version: go1.16.13 Git Commit: c99f9f1b6960b98158b7f5fc4e6b5ac1a10b3542 Built: Wed Mar 23 18:33:41 2022 OS/Arch: linux/amd64