This document defines the bindings of the various Network File System (NFS) versions to the Remote Direct Memory Access (RDMA) operations supported by the RPC-over-RDMA transport protocol. It describes the use of direct data placement by means of server-initiated RDMA operations into client-supplied buffers for implementations of NFS versions 2, 3, 4, and 4.1 over such an RDMA transport. This document obsoletes RFC 5667.