CPIC application produces event 3017 - CPIC conversation unknown

MORE INFORMATION

The application sends data to the host. After the application has finished sending the data, it changes the direction by issuing Receive verb. The host responds by returning data to the client AND deallocating the session. This can be seen in the node message trace snippet below:

    ----------------------------------------------- 14:30:51.0031
    05160002->01020101 DLC DATA
                       DAF:02 OAF:02 ODAI:on  Normal
                       RQE FMD EC DR1 CEB
				

The CEB indicates that the host no longer cares about any conversation related matters. When the client receives this chunk of data, you need to inspect the return code on the verb. In this case, it's a CM_DEALLOCATED_NORMAL, which means the conversation has been deallocated normally, and no longer exists.

The application then issues a Deallocate verb as shown below:

    ----------------------------------------------- 14:30:51.0062
    CMDEAL request
     Conversation ID = 01000000
    Conversation characteristics
     Deallocate type = CM_DEALLOCATE_SYNC_LEVEL
     Log data pointer = 00000000
     Log data length = 0
				

The SNA Server, appropriately, responds with a Parameter Check because the conversation no longer exist, as shown below:

    ----------------------------------------------- 14:30:51.0062
    CMDEAL response, result = CM_PROGRAM_PARAMETER_CHECK
				

Summary of the Parameter Check

The application does not need to issue the CMDEAL CPIC verb.