This solution didn't work because groups are specific to the file server implementing them. Your CPU server doesn't know about the groups on your file servers and doesn't itself implement any groups.
I'm suffering more 2ed->4ed migration brain damage. After reading through some of the assorted fileserver code I see what you mean. The [m][ug]id fields in stat seem somewhat arbitrary these days.
It might be nice if fileservers that just make up [ug]ids to satisfy stat or otherwise ignore permissions returned 'none' or something equivalent in those fields, just as a hint.
--lyndon
