The z/OS NFS server supports the WebNFS protocol. WebNFS specification extends the semantics of NFS versions 2, 3 and 4 protocols to allow clients to obtain file handles without the mount protocols. The z/OS® NFS server supports the public filehandle and multi-component lookup features as well as other additional requirements as described in RFC 2055. A keyword, public, is added for the system administrator to specify the public paths that the public file handle can access. A public path for z/OS conventional MVS™ data and a public path for HFS data can both be specified. When a lookup request comes in from an NFS client and an absolute path name is specified, it will be matched with the public paths to determine which public path it is trying to reference. If a relative path is specified and both HFS and MVS public paths are defined then the lookup request will be processed relative to the HFS public path.

The following are restrictions for the WebNFS support provided by the z/OS NFS server in this release.

Export Spanning Pathnames

Lookup requests that reference files or directories outside of the exported public path, will result in an error condition.

Native Path

Only canonical pathnames will be supported.

Canonical path

A canonical path is a hierarchically-related, slash-separated sequence of components, in the form: <directory>/<directory>/.../<name>.

Processing attributes

NFS version 2, version 3, and version 4 public MVS mount does not support attributes inheritance. Therefore server attributes specified with the mount command (such as text, srv_ccsid(), and cln_ccsid()) cannot be inherited when subsequently working with MVS data under a mount point. The z/OS NFS server processes MVS data as binary.

For example, to work with a PDS member a.b.c(text_memb) in text processing mode it is necessary to do a public mount directly to the member:

mount -o vers=x,public zNFSserver:"/a.b.c/text_memb,text" client_mount_path

In this case, the text attribute specified on the mount command will be taken into account when processing the data.