Problem: processes created by ParaStation MPI on remote nodes are not able to access files, if this files have enabled access only for a supplementary group the current user belongs to.

By default, only the primary group is set for newly created processes. To add all groups to a process, set the supplGrps flag within parastation.conf or use the supplementaryGroups directive within psiadmin.

See also the section called “Spawning processes belonging to all groups”.