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pNFS.com is a resource for information regarding Parallel NFS and its standardization as part of NFSv4.1
NFSv4 Working group RFCs for pNFS
The Internet Drafts describing the pNFS standards were published January 2010. The NFS4.1 standard document is large because it includes a complete description of all of NFSv4 as well as the new 4.1 features. There are two companion documents that describe the object layout and block layout for pNFS storage.

  • RFC 5661 This RFC describes NFS version 4 minor version one, including features retained from the base protocol and protocol extensions made subsequently. Major extensions introduced in NFS version 4 minor version one include: Sessions, Directory Delegations, and parallel NFS (pNFS).
  • RFC 5662 This RFC contains the machine readable XDR definitions for the protocol.
  • RFC 5663 This document provides a specification of a block based layout type definition to be used with the NFSv4.1 protocol. As such, this is a companion specification to NFS version 4 Minor Version 1
  • RFC 5664 This document provides a specification of an object based layout type definition to be used with the NFSv4.1 protocol. As such, this is a companion specification to NFS version 4 Minor Version 1

Recent Vendor Gatherings
  • pNFS BoF - NFSv4.1 and pNFS were discussed in a Birds of a Feather (BOF) at the USENIX LISA (25th Large Installation System Administration Conference) 2011 conference, December 5-9, 2011 (Announcement Slides). Vendors are offering pNFS solutions!

What is pNFS?
Parallel NFS (pNFS) is a part of the NFS v4.1 standard that allows clients to access storage devices directly and in parallel. The pNFS architecture eliminates the scalability and performance issues associated with NFS servers in deployment today. This is achieved by the separation of data and metadata, and moving the metadata server out of the data path.

Note that pNFS supports the use of 3 storage protocols in the data path: blocks, objects and files.

Why is it important?
pNFS is important because it brings together the benefits of parallel I/O with the benefits of the ubiquitous standard for network file systems (NFS). This will allow users to experience increased performance and scalability in their storage infrastructure with the added assurance that their investment is safe and their ability to choose best-of-breed solutions remains intact.

    Benefits of Parallel I/O
  • Delivers Very High Application Performance
  • Allows for Massive Scalability without diminished performance

    Benefits of NFS (or most any standard)
  • Ensures Interoperability among vendor solutions
  • Allows Choice of best-of-breed products
  • Eliminates Risks of deploying proprietary technology
Download Source Code for pNFS
If you want to get a head start with pNFS you can download the latest development source code for the pnfs-enabled Linux kernel from linux-nfs.org (provided under the GNU General Public License, Version 2) and the OpenSolaris code from opensolaris.org (under the OpenSolaris Binary License)

The Linux kernel supports various layout drivers for files, objects, and blocks, as well as experimental back-end file systems, such as spnfs and pnfs support for the GFS2 clustered file-system.

Other back-ends are available from several vendors, including EMC (HighRoad), IBM (GPFS2), and Panasas (ActivStor).

If you have questions regarding the source code provided here please contact us at pnfs-info@panasas.com.

Panasas source code is contributed to the open source community by Panasas with the express intention of furthering the rapid adoption of pNFS.
Where can I find more information?