NFS-Ganesha

NFS-ganesha is a user-mode file server for NFS (v3, 4.0,4.1 pNFS). Reliable, Redundant and Fail-safe through clustered configuration:
https://github.com/nfs-ganesha/nfs-ganesha/wiki
http://events.linuxfoundation.org/sites/events/files/slides/Collab14_nfsGanesha.pdf
http://www.snia.org/sites/default/files/Poornima_NFS_GaneshaForClusteredNAS.pdf