Re: FreeBSD 16 nfsd: Unexpected NFS error 'NFS4ERR_NOFILEHANDLE' while probing named attr support

On Sun, Apr 12, 2026 at 6:39 PM Rick Macklem <[email protected]> wrote:
>
> On Sun, Apr 12, 2026 at 6:24 PM Rick Macklem <[email protected]> wrote:
> >
> > On Sun, Apr 12, 2026 at 4:24 PM Dan Shelton <[email protected]> wrote:
> > >
> > > On Mon, 13 Apr 2026 at 01:06, Rick Macklem <[email protected]> wrote:
> > > >
> > > > On Sun, Apr 12, 2026 at 3:58 PM Dan Shelton <[email protected]> wrote:
> > > > >
> > > > > On Wed, 11 Mar 2026 at 01:13, Rick Macklem <[email protected]> wrote:
> > > > > >
> > > > > > On Tue, Mar 10, 2026 at 3:40 PM Dan Shelton <[email protected]> wrote:
> > > > > > >
> > > > > > > Hello,
> > > > > > >
> > > > > > > some odd issue with ms-nfs41-client: when connecting to a FreeBSD
> > > > > > > 16.0-CURRENT main-n284403-895a97c875a0 (installed from
> > > > > > > FreeBSD-16.0-CURRENT-amd64-20260224-16822dac32ab-284159-disc1.iso) NFS server:
> > > > > > >
> > > > > > > Windows side:
> > > > > > > $ /sbin/nfs_mount -o rw 'F:' 'nfs://42.28.16.228//nfsdata'
> > > > > > > Successfully mounted '42.28.16.228@NFS@2049' to drive 'F:'
> > > > > > >
> > > > > > > ms-nfs41-client prints this warning:
> > > > > > > 204c: nfs41_superblock_getattr: Unexpected NFS error
> > > > > > > 'NFS4ERR_NOFILEHANDLE' while probing named attr support
> > > > > > > (the warning comes from
> > > > > > > https://github.com/kofemann/ms-nfs41-client/blob/master/daemon/nfs41_ops.c#L1394)
> > > > > > Hmm. The most obvious cause would be that the file system is not exported.
> > > > > > Check the /etc/exports and, if you use the ZFS nfshare property,
> > > > > > /etc/zfs/exports
> > > > > > and make sure the file system is exported?
> > > > > >
> > > > > > As I've already mentioned, a packet capture is what I use to figure out
> > > > > > what is going on. On the FreeBSD server..
> > > > > > # tcpdump -s 0 -w out.pcap host <windows-client>
> > > > > > - For a simple failure like the above, start it before doing the mount
> > > > > >   and then kill it after the failure and send me "out.pcap".
> > > > > >   (If there is going to be stuff in out.pcap that you need to keep
> > > > > >    confidential, then you'll need to look at out.pcap yourself in wireshare.)
> > > > >
> > > > > We hit this bloody problem several times in February and March.
> > > > > Workaround was to reboot until FILE_NAMED_STREAMS was reported.
> > > > I'll admit I have no idea what you mean by this?
> > >
> > > Windows API: https://learn.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-getvolumeinformationa
> > >
> > > Windows sets the FILE_NAMED_STREAMS flag if a volume supports "Win32
> > > named streams". msnfs41client implements Win32 named streams via NFS
> > > named attr support. If the NFS server does not support NFS named
> > > attrs, then the FILE_NAMED_STREAMS is not enabled, which breaks some
> > > Windows applications.
> > >
> > > Sometimes NFS named attrs are not detected. CAD/CAM customers want my
> > > head because of this right now.
> > The FreeBSD server will only report that it supports named attributes if
> > the exported file system is ZFS with the xattr property set to dir.
> > # zfs set xattr=dir <volume>
> >
> > If this is not the case for all file systems in the mount path, that
> > might explain the problem?
> Also, the "named_attr" attribute will only be true for files that
> have a named attribute directory.
> This might be checked by the client and causes the confusion,
> where it expects "true" even if there is not yet any named attribute
> directory for the file?
Btw, if you find that certain files do need a named attribute directory,
you can go onto the server and...
# runat <file> ls
--> This will create an empty named attribute directory for "<file>",
      if no named attribute directory exists.

rick

>
> rick
>
> >
> > Otherwise, I need to see a packet trace, rick
> >
> > >
> > > >
> > > > >
> > > > > What is the preferred tool to make a package capture on FreeBSD?
> > > > (Assuming you meant packet capture..)
> > >
> > > Yes, classic autocorrect fail. Welcome to the age of AI. Also the day
> > > when my wife says I must not touch coffee.
> > >
> > > >
> > > > # tcpdump -s 0 -w out.pcap host <nfs-client-host>
> > >
> > > Thank you
> > >
> > > Dan
> > > --
> > > Dan Shelton - Cluster Specialist Win/Lin/Bsd
> > >