LU6.2 Session May End Abnormally over Twinax Link (161193)

The information in this article applies to:

Microsoft SNA Server 2.0
Microsoft SNA Server 2.1
Microsoft SNA Server 2.11
Microsoft SNA Server 2.11 SP1

This article was previously published under Q161193

SYMPTOMS

APPC transaction programs (TP) running against an AS/400 over a twinax connection may fail. When this occurs, the AS/400 unbinds the session reporting a sequence number error, UNBIND x'FE' with a sense code of 2001. SNA Server will log the following errors when this occurs:

Event 38: APPC session deactivated abnormally, qualifier = 0003
Event 20: Negative Response Received on Connection <value> (SENSE = 2001)

CAUSE

The AS/400 twinax link interface does not reliably support LU6.2 sessions that use send or receive pacing greater than one.

RESOLUTION

To solve this problem, the send and receive pacing window values in the APPC mode entry (QPCSUPP or QSERVER) should be set to 1.

NOTE: If twinax connection outages are occurring (causing Event 23 errors for the twinax connection), please see the following article in the Microsoft Knowledge Base for an unrelated problem:

160980 Event ID 23, Qualifier 11 While Using Andrew or IBM Twinax Link

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article.
Microsoft is researching this problem and will post more information in this article when the information becomes available.

Modification Type:	Major	Last Reviewed:	11/26/2003
Keywords:	kbbug KB161193