The Connectathon testsuites revealed several flaws in the NFS server implementation in the Linux kernel 2.2.9. The test result from Solaris clients showed that the Solaris NFS client assumes:
However, two fields in the file handle in the Linux NFS server, fb_dentry and fb_dirino, make Solaris's assumption untrue.
fb_dentry is for dentry, which is the internal part for the Linux file system. It determined by pathname. That implies several things:
Those make dentry very unsuitable for file handle. Even worse, dentry is a memory pointer. That means the file handle from the Linux NFS server is not persistent. When the server is rebooted, the file handlers which clients have may become stale and for the same file the Linux NFS server may return a different file handle.