Secondary group membership I have two systems accessing a NAS (Isilon), with local user authentication. On first system (actually two systems with same OSX) running Lion (OSX10.7.5) I used following command:

dscl . -append /Groups/Testers GroupMembership joeuser


Verified his secondary membership with:

dsmemberutil checkmembership -U joeuser -G Testers


This presented "joeuser" to the cluster with access rights based on his secondary group membership and works fine.

On second machine running Mountain Lion (OSX10.8.5) I added &amp; verified joeuser using same commands.

Cluster will not recognize "joe's" secondary membership from the Mountain Lion machine, and will not allow access to directories that were accessible from the Lion machine.

What's changed in user presentation, and how do I fix it / create a secondary membership via different (working) way on the Mountain Lion (and then Mavericks)?
My first thought is that permissions on the NAS have the group "Testers" using the group ID from the Lion machine and that the group has a different ID on the second box.

When you look at permission with the drive connected to the Mountain Lion box does it say group "Tester" has the right privileges or does it give either a different group name or just a number?