Hello
I need some clarification on one point :
we have a PXE server (RedHat 32 bits…), a “big” file about 5GB on it and clients SLES12 SP3 and SP5.
On client, we mount a NFS sharepoint “mount -t nfs -o ro,nolock :/media/CDROM /mnt/tmp” and do a “cp -p /mnt/tmp/big_file /tmp”
On SLES12SP3 client : no issue, file is copied
On SLES12SP5 client : file is only copied until it reaches 4GB.
Clients are 64 bits, partitions are ext4, nfs version 4, uname -a shows no limit file size…
In fact, as the NFS server is 32 bits, I would say that it cannot handle file greater than 4GB but as it works for SLES12SP3… 
If someone has an explanation…