SNA Server Can Be "Paused" to Force New Users to Other Servers (182914)


The information in this article applies to:

  • Microsoft SNA Server 3.0 SP1
  • Microsoft SNA Server 3.0 SP2
  • Microsoft SNA Server 3.0 SP3
  • Microsoft SNA Server 4.0
This article was previously published under Q182914

SUMMARY

SNA Server 3.0 Service Pack 1 (SP1) and later versions supports the ability to "Pause" and "Continue" the SNA Server service (SnaServer). When paused, the SNA Server continues to support existing client connections, but refuses new client session requests. This applies to 3270, LUA (including TN3270) and APPC LU types. Administrators can still administer the SNA Server while it is paused. As users stop and restart their SNA session access, users connect against alternate servers that are configured to provide SNA access for the users. This allows an SNA Server to be brought out of service with minimal user disruption.

Using SNA Server 3.0 (SP1 or later), the SNA Server service can be paused and continued, using the Windows NT Control Panel "Services" function. The SNA Server 3.0 Manager interface doesn't support the ability to pause and to resume the server. However, the SNA Server 4.0 Manager and Microsoft Management Console interface do support the ability to pause and resume the server directly from the SNA Server 4.0 management interface.

MORE INFORMATION

When the SNA Server service is paused, new user connection requests are refused. If alternate SNA Servers in the SNA subdomain are configured with SNA session resources and are available to the user, the user will automatically connect to the alternate servers. However, if there is a single SNA Server and it is paused, the following behavior will be observed on the client who attempts to connect to a paused server:
  • An APPC application's [MC_]ALLOCATE request will fail, with the following error:
    primary_rc = 0xF004 (COMM_SUBSYSTEM_NOT_LOADED)
    secondary_rc = 0x010000F0 (or 0xF0000001)
  • A CPIC application's CMALLC request will fail with Error 20 (CM_PRODUCT_SPECIFIC_ERROR)
  • When opening a 3270 emulation session, the Microsoft SNA Server 3270 program displays the following message:
    No SNA Server found in domain.
A 3270 message trace shows that the emulator's Open(SSCP) request fails with an OPEN SSCP RSP ERROR, with Err1:0000, Err2:0000.
  • When opening a TN3270 session through the SNA Server TN3270 Server, where LUA LUs are owned by an SNA Server that has been paused, the SNA Server TN3270 program displays the following error:
    [TN3270-36] ERROR
  • An error occurred during device type/name processing
Modification Type:MinorLast Reviewed:7/16/2004
Keywords:kbinfo KB182914
©2004 Microsoft Corporation. All rights reserved.