4.9 kernel NFS is still broken

     NFS took longer to screw up with the 4.9 kernel than the 4.8 but after several hours it still did, so I have reverted back to a 2.6 kernel on the Centos 6 machines used for mail and shellx.

     It is more important that the machines run properly than fast, though it would be desirable to have them do both.