DOCUMENT:Q170996  13-JUN-2001  [sna]
TITLE   :SNA Server Fails to Send Data to DSPU After an Outage
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:2.11 SP2,3.0,3.0 SP1
OPER/SYS:
KEYWORDS:kbbuglist

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft SNA Server, versions 2.11 SP2, 3.0, 3.0 SP1, on platform(s):
    - the operating system: Microsoft Windows NT 
-------------------------------------------------------------------------------


SYMPTOMS
========

Under certain circumstances, like a link outage between SNA Server and a
Downstream System, SNA Server may fail to send host data to the downstream
System on the SSCP-LU session. Sessions or applications on the downstream system
then seem to hang, waiting for data.

CAUSE
=====

We recently introduced a queue within the SNA Server service to ensure that
requests from the Host on the LU-SSCP session were handled serially.
Unfortunately in one case this queue is not cleared. The particular case is when
the SNA Server service receives a request from the host when the downstream
session or application is not ready to receive data. The EXR or -RSP generated
was not routed through the DFC layer (where the queue was managed).

STATUS
======

Microsoft has confirmed this to be a problem in SNA Server version 2.11 Service
Pack 2, 3.0 and 3.0 Service Pack 1. A fix to this problem is in development, but
has not been regression-tested and may be destabilizing in production
environments.

Microsoft does not recommend implementing this fix at this time. Contact
Microsoft Product Support Services for more information on the availability of
this fix.

Additional query words:

======================================================================
Keywords          :  kbbuglist
Technology        : kbAudDeveloper kbSNAServSearch
Version           : WINDOWS:2.11 SP2,3.0,3.0 SP1
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.