Using DNS SRV to Specify a Global File Namespace with NFS Version 4
RFC 6641

Internet Engineering Task Force (IETF)                       C. Everhart
Request for Comments: 6641                                    W. Adamson
Category: Standards Track                                         NetApp
ISSN: 2070-1721                                                 J. Zhang
                                                                  Google
                                                               June 2012

  Using DNS SRV to Specify a Global File Namespace with NFS Version 4

Abstract

   The NFS version 4 (NFSv4) protocol provides a mechanism for a
   collection of NFS file servers to collaborate in providing an
   organization-wide file namespace.  The DNS SRV Resource Record (RR)
   allows a simple way for an organization to publish the root of its
   file system namespace, even to clients that might not be intimately
   associated with such an organization.  The DNS SRV RR can be used to
   join these organization-wide file namespaces together to allow
   construction of a global, uniform NFS file namespace.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6641.

Everhart, et al.             Standards Track                    [Page 1]
RFC 6641           NFSv4 Global Namespace with DNS SRV         June 2012

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Table of Contents

   1. Background ......................................................3
   2. Requirements Notation ...........................................3
   3. Use of the SRV Resource Record in DNS ...........................3
   4. Integration with Use of NFS Version 4 ...........................5
      4.1. Globally Useful Names: Conventional Mount Point ............5
      4.2. Mount Options ..............................................6
      4.3. File System Integration Issues .............................6
      4.4. Multicast DNS ..............................................7
   5. Where Is This Integration Carried Out? ..........................7
   6. Security Considerations .........................................7
   7. IANA Considerations .............................................9
   8. References ......................................................9
      8.1. Normative References .......................................9
      8.2. Informative References ....................................10

Everhart, et al.             Standards Track                    [Page 2]
RFC 6641           NFSv4 Global Namespace with DNS SRV         June 2012

1.  Background

   Version 4 of the NFS protocol [RFC3530] introduced the fs_locations
   attribute.  Use of this attribute was elaborated further in the NFSv4
   minor version 1 protocol [RFC5661], which also defined an extended
   version of the attribute as fs_locations_info.  With the advent of
   these attributes, NFS servers can cooperate to build a file namespace
   that crosses server boundaries.  The fs_locations and