Q163745: Explanation of DNS Notify List "Secondary Notification" Behavior

Article: Q163745
Product(s): Microsoft Windows NT
Version(s): WinNT:4.0
Operating System(s): 
Keyword(s): kbusage
Last Modified: 10-AUG-2001

-------------------------------------------------------------------------------
The information in this article applies to:

- Microsoft Windows NT Server version 4.0 
-------------------------------------------------------------------------------

SUMMARY
=======

Microsoft Windows NT Primary Domain Name Service (DNS) Servers do not send
change notification messages to Secondary DNS Servers that are included on the
Primary's Notify List until selecting the menu option "DNS/Update Server Data
Files".

MORE INFORMATION
================

Microsoft Windows NT DNS Server allows the Administrator to specify (on the
Primary DNS Server) any Secondary DNS Servers that should be notified
immediately of changes to the Zone file. When Zone changes occur, the Primary
name server sends DNS change notification messages to all Secondary name servers
on the list. When notified, the Secondary name server can query the SOA record
on the Primary immediately, without waiting for the Refresh Interval to expire.

The notification process does not occur until the "DNS/Update Server Data Files"
menu item is selected. Since there is no Incremental Zone transfer capability,
when a Zone Transfer is triggered, the entire Zone file is transferred - not
just changes made to the zone file.

Normally, the Administrator will make several changes in a single administrative
session. If the Secondary DNS Servers were notified after every change, there
would be a continuous stream of Zone transfers during a single session,
generating unnecessary network traffic. Waiting for the Administrator to trigger
the process by selecting "DNS/Update Server Data Files" prevents continuous Zone
transfers.

Additional query words: dnsmgr
======================================================================
Keywords          : kbusage 
Technology        : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTS400search kbWinNTS400
Version           : WinNT:4.0

=============================================================================