DOCUMENT:Q114541 08-AUG-2001 [winnt] TITLE :TCP/IP-based Applications Hang on Multiprocessor Systems PRODUCT :Microsoft Windows NT PROD/VER:winnt:3.1; :3.1 OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 3.1 - Microsoft Windows NT Workstation version 3.1 - Microsoft Windows NT Advanced Server, version 3.1 ------------------------------------------------------------------------------- SYMPTOMS ======== TCP/IP-based applications may hang on multiprocessor systems. A sniff of the problem shows the Windows NT machine receiving and ACKing a FIN, but never sending its corresponding FIN. CAUSE ===== The TCP/IP stack does not send a disconnect indication to the application if the packet with the FIN bit set is being processed by one processor while a previous data packet is concurrently being processed on another processor. This can occur when two NDIS DPCs run concurrently on the same interface, which is possible only on multiprocessor systems. RESOLUTION ========== None available at this time. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT and Windows NT Advanced Server version 3.1. This problem has been corrected in the latest U.S. Service Pack for Windows NT and Windows NT Advanced Server version 3.1. 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: prodnt ====================================================================== Keywords : kbnetwork Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW310 kbWinNTSsearch kbWinNTS310 kbWinNTAdvSerSearch kbWinNTAdvServ310 kbWinNTS310search kbWinNT310Search kbWinNTW310Search Version : winnt:3.1; :3.1 ============================================================================= 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.