DOCUMENT:Q197864 04-JUN-2001 [winnt] TITLE :Cannot Ping a WLBS Server from Another WLBS Server PRODUCT :Microsoft Windows NT PROD/VER::4.0 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server, Enterprise Edition - Microsoft Windows NT Server version 4.0 - Microsoft Windows NT Load Balancing Service ------------------------------------------------------------------------------- SYMPTOMS ======== When you ping a cluster host's dedicated IP address from another cluster host, you receive no response. CAUSE ===== This issue is a single network interface card (NIC) limitation. If you are using a single NIC and have not selected the Windows NT Load Balancing Service (WLBS) multicast support, the cluster hosts will not be able to communicate with each other even though they can exchange network traffic with outside systems. NOTE: On a cluster host with multiple NICs (multihomed), using the Virtual NIC to access the dedicated IP address (IP address bound to the virtual NIC but configured not to be load balanced) of another multihomed cluster host causes WLBS to consider this a single-NIC configuration RESOLUTION ========== To resolve this issue, select multicast support in the WLBS Setup dialog box to eliminate this problem. Additional query words: Convoy NLB ====================================================================== Keywords : Technology : kbWinNTsearch kbWinNT400xsearch kbWinNTSsearch kbWinNTSEntSearch kbWinNTS400xsearch kbWinNTS400 kbWinNTLBSSearch Version : :4.0 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.