ms-nfs41-client mount to FreeBSD 16.0 nfsd fails in VM with NAT

Lionel Cons <[email protected]> Tue, 2 Jun 2026 18:51:21 +0200

Newsgroups	gmane.os.freebsd.devel.hackers
Message-ID	<CAPJSo4U8w-HqaGo08aesLng_AAgrDz9rnQ6BrEA+sKEwnyxEiw@mail.gmail.com>

We've hit a problem with ms-nfs41-client release 2026-06-01 with FreeBSD 16.0:

If Windows runs in a VM with NAT an attempt to mount fails with Error
Code 59 (Unexpected network error), but if the VM has an IPv4 or IPv6
address the mount succeeds.

Lab technician says that it might be a problem that FreeBSD nfsd
rejects TCP connections from ports < 1024, "... because NAT cannot do
that automatically... " (yay, cryptic, and then he went home...).

Can anyone please elaborate this in more detail?

Lionel