Earlier NFS client implementations use only a single TCP connection with a mount. In ONTAP, a single TCP connection can become a bottleneck with increasing IOPS. However, an nconnect-enabled client can have multiple TCP connections (up to 16) associated with a single NFS mount. Such an NFS client multiplexes file operations onto multiple TCP connections in a round-robin fashion and thus obtains higher throughput from the available network bandwidth. Nconnect is recommended for NFSv3 and NFSv4.1 mounts only.

See your NFS client documentation to confirm whether nconnect is supported in your client version.

NFSv4.1 is enabled by default in ONTAP 9.9.1 and later. In earlier releases, you can enable it by specifying the -v4.1 option and setting it to enabled when creating an NFS server on the storage virtual machine (SVM).

ONTAP does not support NFSv4.1 directory and file level delegations.