Why are VTAM cross-domain sessions failing with sense code 08970007?

There are two VTAM hosts involved. Each host has the same switched major node defined to it. On one host (HOSTA), the resources are in ACTIV (Active) state. On the other host (HOSTB), the resources are in CONCT (Connectable) state.

If the same application program or dependent LU is defined on more that one VTAM simultaneously, and the SNA search logic locates the nonactive instance before it locates the active instance, the session will fail with that sense code if the DUPDEFS start option is set to NONE, indicating that duplicate LU definitions are not allowed, so VTAM should not continue searching for a resource when it is found but not active. In this case, DUPDEFS was set to NONE, so the session was failed when the nonactive instance of the LU was found and it was determined that duplicate LU definitions are not allowed, preventing further searching for the LU.

Issue one of the following commands to modify the VTAM start option of DUPDEFS, which should be set to ALL or DEPLU to resolve this issue:

• F NET,VTAMOPTS,DUPDEFS=ALL

• F NET,VTAMOPTS,DUPDEFS=DEPLU

Specifying DUPDEFS=ALL means that application programs and dependent LUs may be duplicated on this and other VTAMs. Specifiying DUPDEFS=DEPLU means that only dependent LU definitions may be duplicated. Note: This solution works for this specific instance of the 08970007 sense. It may not work in all cases where sense 08970007 is issued.