After a bit more research and thought, It seems that NFS without Kerberos isn't secure, and I'm not implementing Kerberos - so I'm not implementing NFS.  I was already part way to the hinted at and directly proposed solution: rsync-over-ssh for backup, and Read-Only SMB for media sharing.  NFS would be more elegant, but without proper security its not acceptable to me for my private files.

Thanks to everyone for the responses: it helped me figure out what I wanted to do.

On 26 February 2018 at 04:05, Robert Brockway via talk <talk@gtalug.org> wrote:
On Thu, 22 Feb 2018, Lennart Sorensen via talk wrote:

My understanding of NFSv4 is that it is not NFS.  It is something new
and complicated that is way beyond what previous NFS versions did.
Sure it's called NFS, but it's different.

It is quite different but since NFS 4.1 it has looked the same at least. I'm able to switch between NFS & NFS4 in /etc/fstab and remount filesystems using a different version of the protocol.  I've had to do this for debugging a few times.

I found something that seems to indicate it is possible to make NFSv4
run without kerberos and all that:
https://lists.debian.org/debian-user/2017/10/msg00476.html

I've run 4.1 without Kerberos for years.

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