Re: FYI: Readdir not allowed on NFS pseudo root
Stevan Steve Allen <scallen <at> us.ibm.com>
2004-05-16 04:18:53 GMT
Spencer, my intro to Open Systems is still somewhat
limited. Without mount support in v4, are you inquiring about Mount
The operating system is IBM z/OS which contains a
flat filesystem with a UNIX layer. The z/OS NFSv3 server will access
files directly (filesysA) or through the UNIX layer (filesysB).
Basically, z/OS NFSv3 represents two unconnected filesystems
where NFSv4 has introduced a connecting root.
The flat file system is represented by qualified filenames
such as USER.PROJECTS.NFS.ATTR. A problem for z/OS NFSv3 is a READDIR
of the flat filesystem root represents every file in the system. This
is not permitted by the z/OS catalog facility due to the output size.
To address the z/OS 'list all' restriction, z/OS mount
support REQUIRES a mount on a filename prefix or UNIX directory. NFSv3
converts flat filenames to a hierarchical directory structure. A
mount location may be USER or NFS.EXPORTED or /HFS/u/pub allowing a READDIR
from this point on.
The current plan is to return NFS4ERR_NOENT
for a READDIR of the NFSv4 pseudo root. e.g. the pseudo root will
take on the current restrictions of the flat filesys root.
z/OS NFSv3 Pubs:
On May 15, 2004, at 10:26 AM, Stevan Steve Allen wrote:
> Our NFS server sits on top of two operating systems, one UNIX and
> non hierarchical. An OS restriction in this environment is READDIR
> not allowed from the new NFS pseudo root. Lookup will be allowed.
> A GETATTR for our NFS pseudo root will return a mode with execute
> permission bits on to permit change dir, all read and write mode bits
> are off.
Would you be able to be more specific about the operating
environments for which this server will be available? This will
allow the client implementors to be able to respond to user
questions about things not working when the client mounts / from