DOCUMENT:Q163267 09-AUG-2001 [winnt] TITLE :Delay While Establishing SPX II Connection PRODUCT :Microsoft Windows NT PROD/VER:winnt:3.51,4.0 OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- 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 ======== While establishing an SPX II connection, you may experience approximately a five second delay during the SPX session setup. CAUSE ===== When establishing a SPX II session, you follow these steps. - Client - SPX II Connection Request - Host - Extended SPX II ACK - Client - Negotiate Size Request - Host - Extended SPX II ACK (Negotiate Size ACK) - Host - Session Setup/Negotiate Size - Client - Extended SPX II ACK (Negotiate Size ACK) When Windows NT sends the last Client ACK, it does not require an ACK to be returned (does not turn on the acknowledge bit). The server, in these cases, is waiting for a packet that requires an ACK to start transmission. Apparently, during the session setup phase of SPX II, it is OK to require that all packets have the ACK bit set. Because the client did not require an ACK on the last packet of the negotiation, the Novell server does not start sending data, as we would normally expect it to. Instead, we timeout the NWLNKSPX Parameter for KeepAliveTimeout (which defaults to 12), which is a measurement in half seconds. This is the delay before a packet that requires an ACK is sent, and this starts the server going again. Sample Trace of an SPX II Connection with This Failure ------------------------------------------------------ Time Src MAC Addr Dst MAC Addr Protocol Description 0.245 Client The Server ConCtrl = 0xCC, DtaStrm = 0x00, 0xE3A0 -> 0xFFFF 0.247 The Server Client ConCtrl = 0x8C, DtaStrm = 0x00, 0x235C -> 0xE3A0 0.249 Client The Server ConCtrl = 0xCC, DtaStrm = 0x00, 0xE3A0 -> 0x235C 0.252 The Server Client ConCtrl = 0x8C, DtaStrm = 0x00, 0x235C -> 0xE3A0 0.270 The Server Client ConCtrl = 0xCC, DtaStrm = 0x00, 0x235C -> 0xE3A0 0.270 Client The Server ConCtrl = 0x8C, DtaStrm = 0x00, 0xE3A0 -> 0x235C 6.223 Client The Server ConCtrl = 0xC8, DtaStrm = 0x00, 0xE3A0 -> 0x235C 6.224 The Server Client ConCtrl = 0x88, DtaStrm = 0x00, 0x235C -> 0xE3A0 STATUS ====== Microsoft has confirmed this to be a problem in Windows NT version 3.51. We are researching this problem and will post new information here as it becomes available. Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. 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 Silent RIP ====================================================================== Keywords : kbnetwork Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT351search kbWinNT400search kbWinNTW351search kbWinNTW351 kbWinNTSsearch kbWinNTS400search kbWinNTS400 kbWinNTS351 kbWinNTS351search Version : winnt:3.51,4.0 ============================================================================= 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.