DOCUMENT:Q155986 09-AUG-2001 [winnt] TITLE :NetBT Communication Slow on Multihomed Client PRODUCT :Microsoft Windows NT PROD/VER:winnt: OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server ------------------------------------------------------------------------------- SYMPTOMS ======== When you communicate using NetBIOS over TCP/IP (NetBT) to a device that uses the second interface of a multihomed Windows NT client, the initial session establishment is slow. CAUSE ===== This problem will only be seen in environments in which the subnets on both sides of the Windows NT client are not configured to communicate with each other. RESOLUTION ========== Define a route, either per client or on the routers, to allow accessibility to both adapters on the computer running Windows NT Server. MORE INFORMATION ================ NetBT first defines the IP address on the source packet of a three-way handshake using the IP address of the adapter that resolved the name. If this fails, NetBT uses the IP address of the second adapter. This can cause a delay of up to 50 seconds in the establishment of the connection. NOTE: In Windows NT version 4.0 and Windows NT version 4.0 Service Pack 2, significant network connection enhancements have been added to improve connectivity for multi-homed computers. For detailed information, please see the following articles in the Microsoft Knowledge base: ARTICLE ID: Q161425 TITLE: WinNT 4.0 SP2 Multihomed Computer Connection Enhancement ARTICLE ID: Q166159 TITLE: NetBIOS Connections from a Multihomed Computer Additional query words: ====================================================================== Keywords : kbnetwork Technology : kbWinNTsearch kbWinNTSsearch Version : winnt: ============================================================================= 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.