Re: FreeBSD nfsroot - will it work with NFSv4.2?

On Thu, 19 Feb 2026 at 23:30, Rick Macklem <[email protected]> wrote:
>
> On Thu, Feb 19, 2026 at 2:23 PM Dan Shelton <[email protected]> wrote:
> >
> > Hello,
> >
> > Will a FreeBSD 15.0 diskless setup with nfsroot work with NFSv4.2?
> Nope. On FreeBSD a diskless NFS root fs must be NFSv3.

Which is a bit of a problem since our IT guidelines prohibit the use of NFSv3.
Also, we assume that NFSv4.2 will perform much better, and we need ACL support.

> (There are various bootstrap issues, such as a standalone NFS client
> that does not do NFSv4.

Do you have a full list?

> There is also the handling of
> uid/gid<-->user/group name
> mappings by nfsuserd, which cannot be running until it is booted.
> Yes, there are ways to handle the mappings:
> - Do it like Linux and insist that it be uid/gid numbers in the strings.
> or
> - Hardwire enough mappings in the kernel to get the system going so
>   that nfsuserd can run.

Can such a list be built in, or passed as a boot argument string?

>
> Since there has not been any demand for NFSv4 diskless root file
> systems, it has not been done.

We have demand, if we get a contract for that cluster setup... which
requires that this actually works in a demonstrator.

I recall that there was this topic when Opensolaris.org was active,
but I never followed the SUN bugster RFE to implement that feature.
Everyone was just bloody crazy that ZFS will take over the world, so
cluster setups with nfsroot were treated like the orphaned stepchild
which also has rabies and scabies.

Dan
-- 
Dan Shelton - Cluster Specialist Win/Lin/Bsd