NFSv4.2 inter server to server COPY

configname: CONFIG_NFSD_V4_2_INTER_SSC

Linux Kernel Configuration
└─>File systems
└─>Network File Systems
└─>NFSv4.2 inter server to server COPY
In linux kernel since version 5.1 (release Date: 2019-05-05)  
This option enables support for NFSv4.2 inter server to
server copy where the destination server calls the NFSv4.2
client to read the data to copy from the source server.

If unsure, say N.