If an error log indicates that the route to the remote location cannot be found, the Start Pass-Through (STRPASTHR) command attempts to make the connection again. The STRPASTHR command has built-in detailed diagnostic capabilities that exceed those provided by other interfaces that use APPN, or HPR networks. These diagnostic capabilities include problem analysis, functions for problem and error logging (including directory services search information), and route calculation information. However, the system records all session initiation errors in the error log.
When a STRPASTHR command fails to contact a remote location in an APPN network, a record is written to the problem log. The record is written if there is an associated problem record for analyzing the data. The Work with Problems (WRKPRB) and Analyze Problem (ANZPRB) commands enable you to examine and interpret the problem log to help you isolate the problem.
The Display APPN Information (DSPAPPNINF) command can help you understand the topology of your network. It displays the names of all known remote control points and their locations, intermediate sessions, and link status information. The Work with APPN Status (WRKAPPNSTS) command provides session-related information for advanced program-to-program communications (APPC) controller descriptions. These controller descriptions represent connections to adjacent systems by using Advanced Peer-to-Peer Networking® (APPN), or high-performance routing (HPR).
If no problem record exists for a particular type of error, the system does not record a message in the problem log. However, the system records all errors in the error log. The error log entry may help your service personnel isolate the problem.
If you have a communication problem specifically related to APPN and HPR running over your system, reviewing the following topics might also help in troubleshooting: