If an EE connection is suffering connectivity problems and is in the process of timing out (see How Enterprise Extender times out an inactive connection), the VTAM® topology still thinks that EE is a viable route and might select it as the best route to that partner. If the EE link is truly experiencing problems (no inbound data in this case), RTP pipes eventually suffer problems as well. The RTP pipes will go into a path switch state fairly quickly. HPR path switch timers should be set long enough for the APPN topology to be updated to reflect the fact that the EE connection is no longer usable. This means that the HPRPST must be set longer than the time it takes for the EE connection to timeout. In Figure 1, all the HPRPST values should be coded larger than 75S (75 seconds) to outlast the time it takes for an EE connection to time out because of inactivity.

Alternatively, you can specify HPRPSDLY=EEDELAY on the appropriate major node for your EE configuration. The HPRPSDLY parameter is available on the PU definition statement in the switched and model (DYNTYPE=EE) major nodes, and also on the connection network GROUP definition statements in the EE XCA major node. For more information about the HPRPSDLY parameter, see z/OS Communications Server: SNA Resource Definition Reference.