NFS Over TCP
The default transport protocol for the NFS protocol is TCP (Transmission Control
Protocol). TCP helps performance on slow networks and wide area networks. TCP also provides
congestion control and error recovery. NFS over TCP works with the NFS Version 2, NFS Version 3,
and NFS Version 4 protocols.
If InfiniBand hardware is available on the system, the default transport protocol changes from
TCP to the Remote Direct Memory Access (RDMA) protocol. For more information, see Overview of NFS Over RDMA
. Note that, if you use the –proto=tcp
NFS mounts are forced to use TCP only.