SNA Server May Fail to Reestablish a Session Under Certain Conditions

ID: Q235959

The information in this article applies to:

Microsoft SNA Server, versions 4.0, 4.0 SP1, 4.0 SP2

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

Keywords : sna4sp3fix sna4 sna4sp1 sna4sp2
Version : WINDOWS:4.0,4.0 SP1,4.0 SP2
Platform : WINDOWS
Issue type : kbbug