2010-01-07 08:59:40

by Bian Naimeng

Subject: whether can NFS exports option 'nohide' work?

Hi,

I want to use this option=81C but i find it doesn't work at RHEL5.4GA a=
nd Fedora12.

My /etc/exports like this:
# cat /etc/exports
/nfsroot/nfsv4 127.0.0.1(rw,nohide,fsid=3D0)
/nfsroot/nfsv4/dir1 127.0.0.1(rw,nohide,crossmnt)
/nfsroot/nfsv4/dir2 127.0.0.1(rw,nohide,crossmnt)

Then:

# mkdir /nfsroot/nfsv4/dir1/tmpdir
# echo "best wishes" > /nfsroot/nfsv4/dir1/file1
# echo "happy new year" > /nfsroot/nfsv4/dir2/file2

# service nfs restart
# mount -t nfs4 127.0.0.1:/dir2 /nfsroot/nfsv4/dir1/tmpdir
# mount -t nfs4 127.0.0.1:/dir1 /mnt

There is file2 at /nfsroot/nfsv4/dir1/tmpdir, but nothing at /mnt/tmpdi=
r.
I'm not sure i have used it correctly, and whether it really work?=20
Thanks for your help.

--=20
Best Regards
Bian

2010-01-08 05:02:07

by J. Bruce Fields

Subject: Re: whether can NFS exports option 'nohide' work?

On Thu, Jan 07, 2010 at 04:58:28PM +0800, Bian Naimeng wrote:
> Hi,
>=20
> I want to use this option=EF=BC=8C but i find it doesn't work at RHEL=
5.4GA and Fedora12.
>=20
> My /etc/exports like this:
> # cat /etc/exports
> /nfsroot/nfsv4 127.0.0.1(rw,nohide,fsid=3D0)
> /nfsroot/nfsv4/dir1 127.0.0.1(rw,nohide,crossmnt)
> /nfsroot/nfsv4/dir2 127.0.0.1(rw,nohide,crossmnt)
>=20
> Then:
>=20
> # mkdir /nfsroot/nfsv4/dir1/tmpdir
> # echo "best wishes" > /nfsroot/nfsv4/dir1/file1
> # echo "happy new year" > /nfsroot/nfsv4/dir2/file2
>=20
> # service nfs restart
> # mount -t nfs4 127.0.0.1:/dir2 /nfsroot/nfsv4/dir1/tmpdir
> # mount -t nfs4 127.0.0.1:/dir1 /mnt
>=20
> There is file2 at /nfsroot/nfsv4/dir1/tmpdir, but nothing at /mnt/tmp=
dir.
> I'm not sure i have used it correctly, and whether it really work?=20
> Thanks for your help.

You can't re-export nfs filesystems.

(I wonder why we aren't warning about this?)

--b.

2010-01-08 09:50:56

by Bian Naimeng

Subject: Re: whether can NFS exports option 'nohide' work?

J. Bruce Fields =8E=CA=93=B9:
> On Thu, Jan 07, 2010 at 04:58:28PM +0800, Bian Naimeng wrote:
>> Hi,
>>
>> I want to use this option=81C but i find it doesn't work at RHEL5.4G=
A and Fedora12.
>>
>> My /etc/exports like this:
>> # cat /etc/exports
>> /nfsroot/nfsv4 127.0.0.1(rw,nohide,fsid=3D0)
>> /nfsroot/nfsv4/dir1 127.0.0.1(rw,nohide,crossmnt)
>> /nfsroot/nfsv4/dir2 127.0.0.1(rw,nohide,crossmnt)
>>
>> Then:
>>
>> # mkdir /nfsroot/nfsv4/dir1/tmpdir
>> # echo "best wishes" > /nfsroot/nfsv4/dir1/file1
>> # echo "happy new year" > /nfsroot/nfsv4/dir2/file2
>>
>> # service nfs restart
>> # mount -t nfs4 127.0.0.1:/dir2 /nfsroot/nfsv4/dir1/tmpdir
>> # mount -t nfs4 127.0.0.1:/dir1 /mnt
>>
>> There is file2 at /nfsroot/nfsv4/dir1/tmpdir, but nothing at /mnt/tm=
pdir.
>> I'm not sure i have used it correctly, and whether it really work?=20
>> Thanks for your help.
>=20
> You can't re-export nfs filesystems.
>=20
> (I wonder why we aren't warning about this?)
>=20

Though i does not mount nfs filesystem, instead by ext3 filesystem /d=
ev/hda,
there is not anyting at /mnt/tmpdir.

# mount /dev/hda3 /nfsroot/nfsv4/dir1/tmpdir
# mount -t nfs4 127.0.0.1:/dir1 /mnt

# ll /mnt/tmpdir/
total 0

Then, i test it at two different RHEL5.4 host.

host1=81infs server=81j:
# cat /etc/exports
/nfsroot/nfsv4 host2(rw,nohide,crossmnt,fsid=3D0)
/nfsroot/nfsv4/dir1 host2(rw,nohide,crossmnt)

# mount /dev/hda3 /nfsroot/nfsv4/dir1/tmpdir

host2 (nfs client):
# mount -t nfs4 host1:/dir1 /mnt
# ll /mnt/
ls: /nfsv4/tmpdir: Stale NFS file handle
total 4
-rw-r--r-- 1 root root 0 Jan 5 2010 file1
drwxr-xr-x 6 root root 4096 Jan 6 2010 tmpdir

# ll /nfsv4/tmpdir
ls: /nfsv4/tmpdir: Stale NFS file handle
ls: /nfsv4/tmpdir: Stale NFS file handle

Best Regards
Bian