I propose a new project that delivers the NFSv4 extensions for Mirror Mounts, Referrals, and Replication & Migration. This project should be endorsed by the NFS community.
What's a mirror mount? It's a way to make the client automatically mount filesystems from the same server as it discovers them. The current Solaris NFS client code does not do this, which forces admins to update their automounter maps when new filesystems are created. ZFS admins would rather be free to create new filesystems and have them discovered. Mirror mounts are described in the NFSv4 RFC 3530, related to the server namespace. For more about how we would like this to work, please see: http://blogs.sun.com/tdh/entry/how_nfsv4_should_work_when What's a referral? It's a pointer a server can give to a client that means, "I don't have the filesystem, but you can find it here." The client will redirect its access to the referred location transparently and continue. A global namespace can be constructed with a mechanism to find an initial global root and referrals. The current project is working on NFSv4.0 (RFC 3530) referral support on the client, with work to follow on NFSv4.1 referral extensions. What's replication & migration? RFC 3530 defines support for a server to be able to say, "that filesystem is no longer here, it's over there now" or "another copy of this filesystem lives here." This links the idea of a referral to the actions needed to resynchronize state of files the client was already using prior to the migration event. Being able to move and replicate filesystems freely is another part of a global namespace. Initial team: Evan Layton, Alok Aggarwal, Calum Mackay, Rob Thurlow. Rob T
