Q282752: DEACTIVATE_SESSION Verb May Cause Snaservr.exe Hang

Article: Q282752
Product(s): Microsoft SNA Server
Version(s): 4.0 SP3,4.0 SP4
Operating System(s): 
Keyword(s): kbDSupport kbsna400sp3 kbhis2000bug kbsna400sp4
Last Modified: 08-MAY-2002

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The information in this article applies to:

- Microsoft SNA Server, versions 4.0 SP3, 4.0 SP4 
- Microsoft Host Integration Server 2000 
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SYMPTOMS
========

The SNA Server service (Snaservr.exe) may exhibit one of the following symptoms
when it receives a DEACTIVATE_SESSION verb from an Advanced Program-to-Program
Communications (APPC) application:

- High CPU (for example, 99% - 100%) use for the SNA Server (Snaservr.exe)
  process.

-or-

- SNA Server service stops responding (hangs) when terminating the APPC
  application that issued the DEACTIVATE_SESSION verb.

CAUSE
=====

If the SNA Server service receives a DEACTIVATE_SESSION (All Sessions) verb at
the same time as an UNBIND request for one of the sessions that is being
deactivated, the SNA Server service may experience one of the two problems
described in the "Symptoms" session.

If the DEACTIVATE_SESSION verb is received just prior to the UNBIND request, the
SNA Server service will stop responding (hang). If the UNBIND request is
received just prior to the DEACTIVATE_SESSION verb, the SNA Server service will
show 100% CPU use.

RESOLUTION
==========

A supported fix is now available from Microsoft, but it is only intended to
correct the problem described in this article and should be applied only to
systems experiencing this specific problem. This fix may receive additional
testing at a later time, to further ensure product quality. Therefore, if you
are not severely affected by this problem, Microsoft recommends that you wait
for the next Microsoft SNA Server version 4.0 or Host Integration Server 2000
service pack that contains this fix.

To resolve this problem immediately, contact Microsoft Product Support Services
to obtain the fix. For a complete list of Microsoft Product Support Services
phone numbers and information about support costs, please go to the following
address on the World Wide Web:

  http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are normally incurred for support calls may
be canceled, if a Microsoft Support Professional determines that a specific
update will resolve your problem. Normal support costs will apply to additional
support questions and issues that do not qualify for the specific update in
question.

The English version of this fix should have the following file attributes or
later:

SNA Server 4.0

+-------------------------------------+
| File name    | Date       | Time    | 
+-------------------------------------+
| Snaservr.exe | 12/18/2000 | 09:00AM | 
+-------------------------------------+

NOTE: Because of file dependencies, the most recent fix that contains the above
files may also contain additional files.




STATUS
======

Microsoft has confirmed this to be a problem in Microsoft SNA Server versions
4.0 Service Pack 3 (SP3), 4.0 Service Pack 4 (SP4), and Host Integration Server
(HIS) 2000.

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

For more information on the DEACTIVATE_SESSION and ACTIVATE_SESSION verbs,
please refer to the APPC Programmer's Guide in the SNA Server 4.0 SP3 (or later)
and Host Integration Server 2000 SDK.

For additional information about these two APPC verbs, click the article numbers
below to view the articles in the Microsoft Knowledge Base:

  Q195010 Activate_session/Deactivate_session Unavailable in SNA Server

  Q263096 ACTIVATE_SESSION Event Not Signaled When the Session Ends

  Q245966 Winmgt32.dll May Complete Same Verb Three Times

  Q279879 Problems with Processing Of Asynchronous CNOS and DISPLAY Verbs

  Q282461 DEACTIVATE_SESSION Returns Parameter_Check If No Sessions Are Active

Additional query words: Snaservr sp3 sp4 service pack

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Keywords          : kbDSupport kbsna400sp3 kbhis2000bug kbsna400sp4 
Technology        : kbAudDeveloper kbSNAServSearch kbHostIntegServ2000 kbSNAServ400SP3 kbSNAServ400SP4
Version           : :4.0 SP3,4.0 SP4
Issue type        : kbbug
Solution Type     : kbfix

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