Q180704: SLI_CLOSE May Hang if CICS Doesn’t Respond to SHUTC

Article: Q180704
Product(s): Microsoft SNA Server
Version(s): WINDOWS:3.0,3.0 SP1,3.0 SP2,4.0
Operating System(s): 
Keyword(s): 
Last Modified: 14-MAR-2000

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The information in this article applies to:

- Microsoft SNA Server, versions 3.0, 3.0 SP1, 3.0 SP2, 4.0 
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SYMPTOMS
========

When an SLI application calls SLI_CLOSE, the SLI_CLOSE may never complete if the
host sends an UNBIND request but fails to send a SHUTC response.

This problem was found when connecting an SLI application to CICS. If the CICS
region is stopped and started, in some cases the SLI application's SLI_CLOSE
request failed to complete.

The following API and message sequence summarizes the failure scenario:

SLI Program  SLI API      SNA Server/Host
===========  =========    =================
 < SLI program in session with the host >

SLI_BID ->
                         <- SHUTD
            <- SLI_BID (LUA_SESSION_END_REQUESTED)
SLI_CLOSE ->
            SHUTD +RSP ->
            CHASE ->
                         <- CHASE +RSP
            SHUTC ->
                         <- UNBIND (type 01 = normal)
            SENSE 08390000 ->
                         UNBIND +RSP ->

CAUSE
=====

The SLI interface was hanging if it received an UNBIND when waiting for a SHUTC
response.

STATUS
======

Microsoft has confirmed this to be a problem in SNA Server version 3.0, 3.0
Service Pack 1 (SP1), 3.0 SP2, and 4.0.

This problem was corrected in the latest SNA Server versions 3.0 and 4.0 U.S.
Service Packs. For information on obtaining these Service Packs, query on the
following word in the Microsoft Knowledge Base (without the spaces):

  S E R V P A C K

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

With this update applied, the SLI interface will now complete the SLI_CLOSE if
an UNBIND is received, even if no SHUTC response is received.

Additional query words:

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Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ400 kbSNAServ300SP1 kbSNAServ300SP2
Version           : WINDOWS:3.0,3.0 SP1,3.0 SP2,4.0
Issue type        : kbbug
Solution Type     : kbfix

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