Q235959: SNA Server Fails to Reestablish Session Under Certain Conditions

Article: Q235959
Product(s): Microsoft SNA Server
Version(s): WINDOWS:4.0,4.0 SP1,4.0 SP2
Operating System(s): 
Keyword(s): kbsna400sp3fix sna4 kbsna400sp1 kbsna400sp2
Last Modified: 08-MAY-2002

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The information in this article applies to:

- Microsoft SNA Server, versions 4.0, 4.0 SP1, 4.0 SP2 
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SYMPTOMS
========

An attempt to reestablish a disconnected session may fail unless the connection
is stopped and restarted.

CAUSE
=====

SNA Server does not correlate Host SSCP responses to the original SSCP request
if the response is unexpected.

RESOLUTION
==========

To resolve this problem, obtain the latest service pack for SNA Server version
4.0. For additional information, please see the following article in the
Microsoft Knowledge Base:

  Q215838 How to Obtain the Latest SNA Server Version 4.0 Service Pack


STATUS
======

Microsoft has confirmed this to be a problem in Microsoft SNA Server, versions
4.0, 4.0SP1, 4.0SP2. This problem was first corrected in SNA Server version 4.0
Service Pack 3.

MORE INFORMATION
================

The symptoms described above can only be seen when the Host is sending an
unexpected response.

In the case reported, the message flow looks as follows:

Host                     SNA Server
===================================
ACTLU RQD       ->

               <-       ACTLU +RSP

               <-       NOTIFY SLU enabled

INITSELF -RSP   ->  
with sense code 0857 0002, SSCP - PLU session not active

NOTIFY +RSP     ->

The message flow shows that the Host is sending an INITSELF -RSP in error, which
is unexpected as a Response to a NOTIFY Request. However, SNA Server treats this
unexpected Response as a Response to its NOTIFY Request. At this point, the Host
and the SNA Server are not synchronized any more as far as this session is
concerned.

Additional query words: reconnect hangs correlator sequence

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Keywords          : kbsna400sp3fix sna4 kbsna400sp1 kbsna400sp2 
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ400 kbSNAServ400SP1 kbSNAServ400SP2
Version           : WINDOWS:4.0,4.0 SP1,4.0 SP2
Issue type        : kbbug
Solution Type     : kbfix

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