KnowledgeBase Archive

An Archive of Early Microsoft KnowledgeBase Articles

View on GitHub

Q164308: Windows NT 4.0 Clients May Refresh WINS Entries Frequently

Article: Q164308
Product(s): Microsoft Windows NT
Version(s): winnt:3.51,4.0
Operating System(s): 
Keyword(s): 
Last Modified: 08-AUG-2001

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

- Microsoft Windows NT Workstation versions 3.51, 4.0 
- Microsoft Windows NT Server versions 3.51, 4.0 
-------------------------------------------------------------------------------

SYMPTOMS
========

Windows NT 4.0 computers that have Remote Access Service (RAS) installed or are
multihomed may refresh their names with a WINS server every 10 minutes, instead
of using the time-to-live (TTL) value returned by the WINS server.

This name refreshing may cause overloaded WINS servers that do not respond
quickly to name registration or name refresh attempts.

CAUSE
=====

When a computer that is already on a network has RAS installed, it becomes a
multihomed system. Typing "ipconfig /all" (without the quote marks) will show
ndiswan adapters present, in addition to the network adapter.

At startup, WINS clients register their NetBIOS names with their assigned WINS
servers. This is done on all adapters that are present. If the name registration
fails on any adapter, the name is marked (in memory) as still needing to be
registered.

Every ten minutes, a name refresh routine is run. It checks the list of names
and, if any of them were not successfully registered, the name is refreshed on
ALL adapters. If the RAS link is not active, the failure to register on it will
cause the name(s) to be refreshed every 10 minutes on the LAN adapter(s) as
well, which can overload WINS servers.

RESOLUTION
==========

A new version of Netbt.sys has been created that no longer exhibits this
problem. It will only attempt to refresh the name on the adapter that
registration failed on in the first place. The other adapter will send a name
refresh at half of the TTL indicated in the registration response.

NOTE: Even with this new version of Netbt.sys, if a multihomed computer receives
name registration responses that contain different TTL values (on different
adapters), the lowest TTL value will be used to determine the refresh interval.
For instance, if adapter "A" receives a name registration response with a TTL of
43,200 (12 hours) and adapter "B" receives a name registration response with a
TTL of 86,400 (24 hours), a refresh will be sent for the name(s) at half of
43,200, or 6 hours, on each adapter.

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT versions 3.51 and
4.0. This problem was corrected in the latest U.S. Service Pack for Windows NT
and Windows NT Server version 4.0. For information on obtaining the Service
Pack, query on the following word in the Microsoft Knowledge Base (without the
spaces):

  S E R V P A C K


Additional query words: multi-homed

======================================================================
Keywords          :  
Technology        : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT400search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS351search
Version           : winnt:3.51,4.0
Issue type        : kbbug

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

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY.