Implicit Incoming LU Not Used After Saving Configuration Change (195747)

SYMPTOMS

A connection that has been working fine using the Implicit Incoming Remote LU feature may fail after a change is made to the SNA Server configuration. The failure appears as a negative response to a BIND sent by the host. The negative response will include sense code 0835 (Invalid Parameter). The pointer in the sense code points to the Network Qualified PLU Network Name Structured Data Subfield in the BIND.

CAUSE

For the problem to occur, the following must be true:

There is more than one Remote APPC LU in the subdomain with the same alias.
This alias must match that which is configured in the "Implicit Incoming Remote LU" field in the Local APPC LU advanced properties.

If both of these criteria are true, after an APPC Local or Remote LU is created or deleted, when saving the new configuration, SNA Server Manager picks the first Remote LU it finds with that name (which may reside on a different server). After this has happened, if SNA Server receives a BIND containing a partner LU name that is not recognized, the BIND will be rejected.

RESOLUTION

SNA Server 3.0

To resolve this problem, obtain the latest service pack for SNA Server version 3.0. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

184307 How to Obtain the Latest SNA Server Version 3.0 Service Pack

SNA Server 4.0

This problem was corrected in the latest Microsoft SNA Server version 4.0 U.S. Service Pack. For information on obtaining this Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K

MORE INFORMATION

The following is an excerpt from a trace showing the problem. In the bind, the Network Qualified PLU Network Name Structured Data Subfield starts at byte 43(h), noted by the ^ mark (byte 0 of the BIND follows the request header, and has a value of 31):

DLC   05160000->01020101 DLC DATA
DLC                      DAF:01 OAF:02 ODAI:off Exp.
DLC                      BIND   RQD SC  FI BC EC DR1
DLC
DLC   ---- Header  at address 01464418, 1 elements ----
DLC   04010004 10112D00 01024286 0100E800     <......-...Bf..Y.>
DLC
DLC   ---- Element at address 0195E230, start 10, end 147 ----
DLC   6B800031 001307B0 B050B300 87898987     <k..1.....P..giig>
DLC   00060200 00000000 00001023 00000FD9     <...........#...R>
DLC   C5C4C5E2 D74BD5F0 F3E2E5F0 F0F22600     <EDESPKN03SV002&amp;.>
DLC   0902E2D5 C1E2E5C3 D4C70903 01A70860     <..SNASVCMG...x.`>
DLC   6FE43B4C 1004D9C5 C4C5E2D7 4BD5F0F3     <oU;L..REDESPKN03>
<WWBLOCKQUOTE>
                   ^^
</WWBLOCKQUOTE>
DLC   E2E5F0F0 F2000FD9 C5C4C5E2 D74BE3F0     <SV002..REDESPKT0>
DLC   C5C4F2F3 C9F26016 ECA70860 6FE43B4C     <ED23I2`..x.`oU;L>
DLC   0DD9C5C4 C5E2D74B C3C4D9C1 C3C12C0A     <.REDESPKCDRACA,.>
DLC   01084040 40404040 4040                  <..@@@@@@@@      >
<BR/><BR/>
The LU name in the subfield is REDESP.N03SV002, however there is no LU by
this name in the SNA Server config. When an Implicit Incoming Remote LU is
configured, SNA Server should treat the BIND as if it contained the
Implicit LU name in this field. In the problem scenario, SNA Server sent a
negative response as follows:
<BR/><BR/>
DLC   01020101->05160000 DLC DATA
DLC                      DAF:02 OAF:01 ODAI:off Exp.
DLC                      BIND   -RSP SC  FI SD BC EC DR1
DLC
DLC   ---- Header  at address 01464418, 1 elements ----
DLC   04010004 10002D00 02014286 0100E800     <......-...Bf..Y.>
DLC
DLC   ---- Element at address 0195E59C, start 10, end 17 ----
DLC   EF900008 35004331                       <....5.C1        >