VNX: Unable to create NFS export with NFSv4only option - error "Nfs has been started with HI_VERS 3. Cannot export as nfsv4 only" (User Correctable)

Customer was trying to create NFS export using NFSv4only option. Running the export command reported error:
Error 22: server_2 : Invalid argument
Export Error: Nfs has been started with HI_VERS 3. Cannot export as nfsv4 only

Example:
server_export server_2 -P nfs -option nfsv4only /ufs1
Error 22: server_2 : Invalid argument
Export Error: Nfs has been started with HI_VERS 3. Cannot export as nfsv4 only

By default, NFSv3 is the active NFS service on the VNX. Customer didn't enable NFSv4 on the VNX

To check run below command:
cat /nas/server/slot_2/config
nfs config

Need to enable NFSv4 on the server to resolve the issue

1. With a text editor, open the /nas/server/slot_x/config file, where is the slot number of the Data Mover.
where: x=Datamover slot

2. On the nfs config line, append the option hivers=4 or, if the option already appears, be sure the value is set to 4.
Save and close the file.
For example: nfs config hivers=4 
Note: Do not change any other lines or options in the file.

3. Restart the Data Mover by using this command syntax:
server_cpu <mover name> -reboot -monitor now 
where: <mover name>=name of the Data Mover

(Refer: Configuring-NFS-on-VNX-8.1, Page 26 )

Then, try to create the export with NFSv4only option:
server_export server_2 -P nfs -option nfsv4only /ufs1
server_2: done

NFSv4 does not support the -name option.