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Improved Recursive DNS Server Selection for Multi-Interfaced Nodes
RFC 6731

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>,
    mif mailing list <>,
    mif chair <>
Subject: Protocol Action: 'Improved Recursive DNS Server Selection for Multi-Interfaced Nodes' to Proposed Standard (draft-ietf-mif-dns-server-selection-12.txt)

The IESG has approved the following document:
- 'Improved Recursive DNS Server Selection for Multi-Interfaced Nodes'
  (draft-ietf-mif-dns-server-selection-12.txt) as Proposed Standard

This document is the product of the Multiple Interfaces Working Group.

The IESG contact persons are Ralph Droms and Brian Haberman.

A URL of this Internet Draft is:

Ballot Text

Technical Summary

   A multi-interfaced node is connected to multiple networks, some of
   which may be utilizing private DNS namespaces.  A node commonly
   receives DNS server configuration information from all connected
   networks.  Some of the DNS servers may have information about
   namespaces other servers do not have.  When a multi-interfaced node
   needs to utilize DNS, the node has to choose which of the servers
   to contact to.  This document describes DHCPv4 and DHCPv6 options
   that can be used to configure nodes with information required to
   perform informed DNS server selection decisions.

Working Group Summary

   There was no controversy about this document, but there were fears
   that this document is actually “promoting use of split-brain
   DNS”. After discussions the concern was tackled in Section 7
   “Considerations for network administrators” with text: ”Private
   namespaces MUST be globally unique in order to keep DNS unambiguous
   and henceforth avoiding caching related issues and destination
   selection problems (see Section 2.3).”

   Another major area that caused lots of discussion was security
   implications caused by risks related to attacker redirecting some
   DNS queries to bad places. This is addressed in Section 4.4.
   “Limitations on use” and in Section 4.1, especially with help of

Document Quality

   There are two implementations of the protocol, one from Nokia, the
   other from NTT. Microsoft also has Name Resolution Policy Table
   implementation. There were thorough reviews of the document, but
   these reviews did not lead to important changes.  There are no
   substantive issues.


   Hui Deng <> is the document shepherd.
   Ralph Droms <> is the responsible AD.

RFC Editor Note