DetailPage-MSS-KB

Microsoft small business knowledge base

Article ID: 957930 - Last Review: November 19, 2008 - Revision: 1.0

SYMPTOMS

Consider the following scenario:
  • A Windows Server 2003 DNS server is configured to use conditional forwarders.
  • A DNS client sends a name resolution query to this DNS server.
  • This query requires forwarding to conditional forwarders.
In this scenario, the name resolution fails, and the conditional forwarders return an error message that resembles the following:
Not Implemented
Notes
  • This issue does not occur if Windows Server 2003 DNS servers forward such a query to root hints.
  • This issue does not occur if you configured the default All other DNS domains option for the Forwarders setting.

CAUSE

This issue occurs because Windows Server 2003 DNS server earlier was not fully compliant with RFC 1035.

In some cases, the Windows Server 2003-based DNS server incorrectly sets the Authoritative Answer (AA) bit when it forwards the query to the conditional forwarders. Some DNS Servers check the AA bit when they receive queries. If the AA bit is set, the query is rejected. This occurs because the AA bit should be set only .in responses for which the responding server is authoritative for a particular domain.

WORKAROUND

To work around the issue, use root hints or the default All other DNS domains option instead of using the conditional forwarders.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

MORE INFORMATION

For more information about RFC 1035, visit the following Web site:
http://www.ietf.org/rfc/rfc1035.txt (http://www.ietf.org/rfc/rfc1035.txt)
Note The AA bit is described on page 25.

When this issue occurs, a network monitor capture may resemble the following:
1              Windows Server 2003 DNS server Third-party DNS server     DNS:QueryId = 0x8022, QUERY (Standard  query), Query  for FQDN of type Host Addr on class Internet
Flags:  Query, Opcode - QUERY (Standard query), AA, RD, Rcode - Success     ==> this is the query  being sent to the conditional forwarder and notice that AA bit is set.

2              Third-party DNS server Windows Server 2003 DNS server     DNS:QueryId = 0x8022, QUERY (Standard  query), Response - Not Implemented ===>error returned by the third party dns server

APPLIES TO
  • Microsoft Windows Server 2003, Datacenter Edition (32-bit x86)
  • Microsoft Windows Server 2003, Datacenter Edition for Itanium-Based Systems
  • Microsoft Windows Server 2003, Datacenter x64 Edition
  • Microsoft Windows Server 2003, Enterprise x64 Edition
  • Microsoft Windows Server 2003, Enterprise Edition (32-bit x86)
  • Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems
  • Microsoft Windows Server 2003, Standard x64 Edition
  • Microsoft Windows Server 2003, Standard Edition (32-bit x86)
Keywords: 
kbexpertiseadvanced kbtshoot kbprb KB957930
Share
Additional support options
Ask The Microsoft Small Business Support Community
Contact Microsoft Small Business Support
Find Microsoft Small Business Support Certified Partner
Find a Microsoft Store For In-Person Small Business Support