DOCUMENT:Q257925 08-AUG-2001 [winnt] TITLE :Cluster Server Does Not Detect Network Problems in Windows NT PRODUCT :Microsoft Windows NT PROD/VER::4.0; winnt:1.0 OPER/SYS: KEYWORDS:kbhw kbnetwork kbHardware ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server, Enterprise Edition version 4.0 - Microsoft Windows NT Server, Enterprise Edition version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== Cluster Server in Windows NT Server 4.0, Enterprise Edition, does not detect network problems. Disconnecting the network cable from the active node does not cause an IP address or group to failover. Also, simulated network adapter failures may not cause an IP address to stop working, or cause Cluster Server to declare that an adapter is down. CAUSE ===== The Cluster service verifies that the IP address is online by checking the network stack to make sure that it is functioning. A network problem does not invalidate the IP addresses that are registered on that adapter. This causes the IP address to stay online even though the route is down. This functionality is included in Microsoft Windows 2000 Advanced Server. STATUS ====== This behavior is by design for Windows NT Server 4.0, Enterprise Edition. MORE INFORMATION ================ For additional information about related topics, click the article numbers below to view the articles in the Microsoft Knowledge Base: Q242600 Network Failure Detection and Recovery in a Server Cluster Q254101 Network Adapter Teaming and Server Clustering Q239924 How to Disable Media Sense for TCP/IP in Windows 2000 Q254651 Cluster Network Role Changes Automatically Q176320 Impact of Network Adapter Failure in a Cluster Additional query words: MSCS ====================================================================== Keywords : kbhw kbnetwork kbHardware Technology : kbWinNTsearch kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search Version : :4.0; winnt:1.0 Issue type : kbprb ============================================================================= 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. Copyright Microsoft Corporation 2001.