SNA Server Rejects Host's BIND Response when the Primary Session Level Pacing Receive Window Size Is Zero

ID: Q223373

The information in this article applies to:

Microsoft SNA Server, version 4.0SP2

SYMPTOMS

After you upgrade your VTAM version to 4.4 on the host, SNA Server starts rejecting the host's BIND responses with an UNBIND(06):

Invalid session parameters:
The BIND negotiation has failed because the primary half-session cannot
support parameters specified by the secondary.

In the Windows NT application log the following event may be seen:

Event ID: 22
Description: APPC session activation failure:
BIND negotiated parameters unacceptable, Sense data = 10050000.

CAUSE

SNA Server checks the BIND response pacing parameters to ensure that the PRIMARY RECEIVE WINDOW FIELD SIZE is equal to THE SECONDARY SEND WINDOW SIZE. If this is not true, then the BIND response is rejected.

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

WORKAROUND

To workaround this problem, change the configuration files on the host that are responsible for coding the BIND image so that the BIND RSP ensures the PRIMARY RCV WINDOW SIZE = THE SECONDARY SEND WINDOW SIZE rather then making byte 13 equal zero.

Also note that IBM has produced a PTF and an APAR that addresses this problem for OS390 V2.5 and VTAM 4.4. For information about obtaining this PTF and APAR, please contact IBM Technical Support or visit IBM's Web site at http://www.ibm.com.

STATUS

Microsoft has confirmed this to be a problem in Microsoft SNA Server version 4.0 Service Pack 2. This problem was first corrected in SNA Server version 4.0 Service Pack 3.

MORE INFORMATION

The IBM Formats Reference Manual indicates the following for byte 13 of a BIND response:

Bits 0-1: Reserved
Bits 2-7: Primary receive window size, in binary, for session-level pacing

NOTE: A value of 0 means no pacing of requests flowing to the primary (for one-stage pacing in the secondary-to-primary direction, this field is redundant with, and will indicate the same value as, the secondary send window size--see byte 8, bits 2-7). The third-party products discussed here are manufactured by vendors independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability.

For information about how to contact , please query in the Knowledge Base for one or more of the following articles:

Q65416 Hardware and Software Third-Party Vendor Contact List, A-K

Q60781 Hardware and Software Third-Party Vendor Contact List, L-P

Q60782 Hardware and Software Third-Party Vendor Contact List, Q-Z

Additional query words: BIND PACING

Keywords : sna4sp3fix
Version : WINDOWS:4.0SP2
Platform : WINDOWS
Issue type : kbbug