Cluster exceptions

These are exceptions to the "each cluster is separate" rule.

• UID/GID is shared from Cluster 2 to Cluster 3 but not strictly enforced.
• disks from Cluster 2 are exported read-only to Cluster 7 during the transition from 2 to 7.
• we will experiment with nfs exports from cluster 2/7 to Cluster 8 aka coreHPC. Research only.
• we tried nfs export from Cluster 2 to Cluster 3 shared/wynton. This was a disaster. Jobs running on wynton overloaded our nfs servers and made them unusable. This will probably happen when we export to cluster 8, but it is worth a try.

No other exceptions known.