DOCUMENT:Q176849 12-JUN-2001 [sna] TITLE :SNA Server Logs Events 684 and 685 When Using SDLC Connection PRODUCT :Microsoft SNA Server PROD/VER:WINDOWS:2.0,2.1,2.11,2.11 SP1,2.11 SP2,3.0,3.0 SP1,3.0 SP2 OPER/SYS: KEYWORDS:kbbuglist ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft SNA Server, versions 2.0, 2.1, 2.11, 2.11 SP1, 2.11 SP2, 3.0, 3.0 SP1, 3.0 SP2 ------------------------------------------------------------------------------- SYMPTOMS ======== An SNA Server computer using an SDLC Link Service for host connections may log the following message in the Windows NT application event log at random intervals: Event ID: 684 Description: A buffer pool audit has been triggered by a pool extension. The description also lists the number of allocated trusted headers. Each successive Event 684 shows a larger number of allocated trusted headers. Eventually the allocated trusted headers will reach the maximum value, and the connection to the host will be lost. At this point, the following message will be logged in the application event log: Event ID: 685 Description: An attempt was made to extend a buffer pool, but the related pool had reached its maximum size. The affected component is terminating, and an audit of the buffer pools just before termination is attached. A trace of the SDLC Link Service shows numerous DLCST UPSN messages (update station statistics) being sent to the SNA Server service. For more information about DLCST UPSN messages, refer to the following Microsoft Knowledge Base article: Q139594 Meaning of "DLCST UPSN" in an SNA Server Data Link Control Trace CAUSE ===== Messages from the Link Service are being placed into the buffer pool much faster than the SNA Server service can process them. This is usually caused by a problem elsewhere in the system, for example, in the SDLC adapter or driver. However, SNA Server should deal with this situation without dropping the host connection. The UPSNSTAT messages let the SNA Server service track statistics for sending in RECFMS messages to the host. RECFMS has been retired from SNA for type 2 nodes, and UPSNSTAT is not in the published Microsoft SNA Device Interface Specification, so UPSNSTAT message handling has been removed from the Ibmsdlc.dll Link Service. This eliminates the effects of the problem. STATUS ====== Microsoft has confirmed this to be a problem in SNA Server version 3.0 Service Pack 2 and earlier. This problem was corrected in the latest SNA Server version 3.0 U.S. Service Pack. For information on obtaining this 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: ====================================================================== Keywords : kbbuglist Technology : kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ200 kbSNAServ211 kbSNAServ210 kbSNAServ211SP1 kbSNAServ211SP2 kbSNAServ300SP1 kbSNAServ300SP2 Version : WINDOWS:2.0,2.1,2.11,2.11 SP1,2.11 SP2,3.0,3.0 SP1,3.0 SP2 Issue type : kbbug Solution Type : kbfix ============================================================================= 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.