Normally MPI will just pick up the host list from Slurm itself. You just need to build MPI against Slurm and it will just grab it. Typically this is transparent to the user. Normally you shouldn't need to pass a host list at all. See: https://slurm.schedmd.com/mpi_guide.html
The canonical way to do it if you need to would be the scontrol show hostnames command against the $SLURM_JOB_NODELIST (https://slurm.schedmd.com/scontrol.html#OPT_hostnames). That will give you the list of hosts your job is set to run on.
-Paul Edmon-
On 8/12/2024 8:34 AM, Jeffrey Layton via slurm-users wrote:
Thanks! I admit I'm not that experienced in Bash. I will give this a whirl as a test.
In the meantime, let ask, what is the "canonical" way to create the host list? It would be nice to have this in the Slurm FAQ somewhere.
Thanks!
Jeff
On Fri, Aug 9, 2024 at 1:32 PM Hermann Schwärzler via slurm-users slurm-users@lists.schedmd.com wrote:
Hi Paul, On 8/9/24 18:45, Paul Edmon via slurm-users wrote: > As I recall I think OpenMPI needs a list that has an entry on each line, > rather than one seperated by a space. See: > > [root@holy7c26401 ~]# echo $SLURM_JOB_NODELIST > holy7c[26401-26405] > [root@holy7c26401 ~]# scontrol show hostnames $SLURM_JOB_NODELIST > holy7c26401 > holy7c26402 > holy7c26403 > holy7c26404 > holy7c26405 > > [root@holy7c26401 ~]# list=$(scontrol show hostname $SLURM_NODELIST) > [root@holy7c26401 ~]# echo $list > holy7c26401 holy7c26402 holy7c26403 holy7c26404 holy7c26405 proper quoting does wonders here (please consult the man-page of bash). If you try echo "$list" you will see that you will get holy7c26401 holy7c26402 holy7c26403 holy7c26404 holy7c26405 So you *can* pass this around in a variable if you use "$variable" whenever you provide it to a utility. Regards, Hermann -- slurm-users mailing list -- slurm-users@lists.schedmd.com To unsubscribe send an email to slurm-users-leave@lists.schedmd.com