NFS versions

NFS was originally developed by Sun Microsystems:


     NFSv2 released in 1985 
     NFSv3 released in 1995 
     NFSv4 released in Dec. 2003 for Sun and NetApp 
           Linux in development stage (Univ. of Michigan)

Detailed info about the NFS versions for Linux is available at http://nfs.sourceforge.net

NFS support should be enabled in Linux Kernel:

CONFIG_NFS_FS=m
CONFIG_NFS_V3=y
CONFIG_NFS_V4=y
CONFIG_NFS_DIRECTIO=y
CONFIG_NFSD=m
CONFIG_NFSD_V3=y
CONFIG_NFSD_V4=y
CONFIG_NFSD_TCP=y

Verify NFS support at run time:

lsmod | grep nfs
grep nfs /proc/filesystems

Verify what NFS version is currently running:

nfsstat

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