System Level Procedures › System Level Procedures › VTAM Messages

VTAM Messages

The VTAM primary program operator (PPO) interface lets your product receive unsolicited messages from VTAM about network events that occur for reasons other than from operator commands. For example, if an NCP fails, VTAM will generate unsolicited messages notifying the PPO application of the occurrence.

The PPO interface can also be fed with commands and responses resulting from operator action at the system console and from OCS windows within the region.

The stream of PPO messages represents a serial record of all unexpected events within the VTAM network. As such it is an ideal source of information about real time network failures.

While PPO messages can be routed automatically to OCS and system console operators for their attention, there is also a virtual user environment within your product called PPOPROC that directly accesses every message (or a chosen subset of messages) received from VTAM. This PPO message flow is accessed only through special NCL verbs:

• The SYSPARMS PPOPROC command nominates the name of a procedure that is to act as the PPOPROC procedure, and as such can execute these special verbs to see and modify PPO messages received from VTAM.
• PPOPROC is a system level procedure (one per system) that acts as a central intelligence point to monitor events being reported by VTAM. As such, it can observe and react to unusual or critical conditions and provide a platform for the collection of additional information about the event and for the initiation of automatic recovery action.