Another Linux Dynamic Pseudo Root patch submitted by Steve Dickson of Redhat
By tdh on Oct 16, 2008
The following patch series gives rpc.mountd the ability to allocate a dynamic pseudo root, so the 'fsid=0' export option is no longer required. This allows v2, v3 and v4 clients mounts without any changes to the server's exports list. One anomaly of the Linux NFS server is that it requires a pseudo root to be defined. Currently the only way a pseudo root can be defined is by setting the fsid to zero (i.e. fsid=0). So if we wanted to make v4 the default mounting version and have things just work like v2/v3 all of the existing exports configurations would have to change (i.e. a 'fsid=0' would have to be added) to support a v4 mounts, which, imho, is unacceptable. So this patch series address this problem.
Steve has really highlighted a huge gap in seamless integration of the Linux NFSv4 implementation into automounters, etc. The path to an export should not change based on the version of the protocol.
Hmm, strike that, from a re-reading of I'm not sure if this patch eliminates my concern about the mount path or not. I.e., above he talks about adding a 'fsid=0' on the server and not what the client has to do about the path.
Time to ask him!
Update: Steve says it does address the mount path issue we've seen in the past.