Twinax Connections Fail

ID: Q171253

The information in this article applies to:

Microsoft SNA Server, versions 3.0 and 3.0 Service Pack 1 (SP1)

SYMPTOMS

A twinaxial connection goes to an Active state in SNA Server Manager after the connection is started, but users are unable to get active APPC sessions on an AS/400 through the twinaxial connection.

The System Operator Log (QSYSOPR) on the AS/400 may contain a message similar to the following after the twinaxial connection on the SNA Server is activated:

   Message ID: CPI6002
   Message: Error detected during TDLC automatic configuration.
   Cause: Your session has ended because of an error found during the
   automatic configuration by twinaxial data link control (TDLC) for device
   <device name>. The device has been varied off.

NOTE: The System Operator Log on the AS/400 can be accessed by entering the following command on an AS/400 command prompt:

   DSPMSG QSYSOPR

The following event may also be logged in the Windows NT Application Event Log on the SNA Server computer:

   Event ID: 96
   Description: Local APPC TP start failed:

      Primary_rc = F004
      Secondary_rc = 010000F0
      TP name = <name of TP>

This problem does not occur when you upgrade SNA Server 2.11 to SNA Server 3.0.

CAUSE

The problem is caused by the way SNA Server 3.0 saves the twinaxial connection properties in the SNA Server configuration. The twinaxial connection is saved as a Peer connection, as are all other connections to AS/400s. The problem is that twinaxial connections are not saved with all of the connection properties that other Peer connections include, such as Peer DLC Role and XID Type.

WORKAROUND

To work around this problem:

Install SNA Server 2.11 and then upgrade to SNA Server 3.0 after getting the twinaxial connection to work under SNA Server 2.11.

STATUS

Microsoft has confirmed this to be a problem in SNA Server version 3.0 and 3.0 Service Pack 1 (SP1). This problem was corrected in the latest SNA Server version 3.0 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

After you apply the updated binary file, do the following so the twinaxial connection will successfully connect to the AS/400:

1. Stop and restart the SnaBase service.

2. Save the SNA Server configuration. If the Save option is greyed out in

   SNA Server Manager, some kind of change will need to be made in the
   configuration before the configuration can be saved.

MORE INFORMATION

The problem is that twinaxial connections are not saved with all of the connection properties that other Peer connections include, such as Peer DLC Role and XID Type. This results in an incorrect sequence when activating a twinaxial connection, as shown below:

   SNA Server                Twinax Link Service
   ----------                -------------------
   Open Link Request   -->
                      <--    Open Link RSP OK
   Open Stat Request   -->
                      <--    Open Stat RSP OK
                      <--    DLCST STCD
                      <--    DLCST RQOS
   DLCST SXID          -->
                      <--    DLCST RQOS

In this sequence, the XID negotiation, shown as SXID and RQOS messages, is done after the Station Contacted (DLCST STCD) message.

The correct sequence when activating a Peer connection is shown below:

   SNA Server                Twinax Link Service
   ----------                -------------------
   Open Link Request   -->
                      <--    Open Link RSP OK
                      <--    DLCST RQOS
   DLCST SXID          -->
                      <--    DLCST RQOS
   DLCST SXID          -->
                      <--    DLCST RQOS
  Open Stat Request    -->
                      <--    Open Stat RSP OK
                      <--    DLCST STCD

In the correct sequence, the XID negotiation occurs before the Open Station (Open Stat) and Station Contacted messages.

SNA Server has been updated to correctly save the twinaxial connection with all of the Peer connection properties and to do the XID negotiation before it does the Open Station sequence.

In addition, the Twinaxial connection properties page will be updated to include a System Identification page. This page will include configuration options for the Local Node Name, Remote Node Name, XID Type, and Peer DLC Role.

Keywords          : kbnetwork snatwinax kbfix3.00.sp2 kbbuglist
Version           : 3.0
Platform          : winnt
Issue type        : kbbug
Solution Type     : kbfix

Last Reviewed: March 21, 1998