That is a bug that should be now fixed in current master. Additionally we added a short test program in `src/pm/hydra/maint` (slurm_nodelist_parse) that you can use to test your node list format to see whether it will cause problems with MPICH. If that fails please provide the output of such program in your message and we will look into it. Giuseppe Congiu Postdoctoral Appointee MCS Division Argonne National Laboratory 9700 South Cass Ave., Lemont, IL 60439 On Dec 4, 2019, at 4:28 PM, Stefan via discuss <[email protected]<mailto:[email protected]>> wrote: Hi, I'm having some issues to make mpirun/mpiexec play nicely with Slurm allocations. I'm using Slurm 19.05.4, and have configured MPICH with: --enable-shared --enable-static --with-slurm=/sw/slurm/19.05.4 \ --with-pm=hydra Now I request resources from Slurm with: $ salloc -N 2 --ntasks-per-node 4 Then when I try to run a test binary: $ mpiexec.hydra ./mpich_hello Error: node list format not recognized. Try using '-hosts=<hostnames>'. Aborted (core dumped) When I do the same with OpenMPI's mpirun/mpiexec it runs on the allocated nodes. Am I missing something, or does MPICH simply not support this use case? Currently I'm working around this by using a script to translate Slurm node allocations into a host list and run like this: $ mpiexec.hydra -hosts $(mpich-host) ./mpich_hello That works fine, but I suppose this workaround should not be necessary. Here is ltrace output which shows that mpiexec tries to process some Slurm related environment variables but apparently fails to do so: https://paste.ubuntu.com/p/327tGrTzq5/ I've also tried with salloc -N 1 -n 1, so that the environment variables are simpler, e.g. SLURM_NODELIST=node-b01 SLURM_TASKS_PER_NODE=1 but that did not change the way mpiexec fails. /Stefan _______________________________________________ discuss mailing list [email protected]<mailto:[email protected]> To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss