System Level Procedures › Intercept Solicited and Unsolicited VTAM Messages (PPOPROC Procedures)

Intercept Solicited and Unsolicited VTAM Messages (PPOPROC Procedures)

The primary program operator interface (PPO) in VTAM can be defined so that your product receives both solicited and unsolicited VTAM messages. An NCL interface, named PPOPROC, is available to the VTAM PPO facility. PPOPROC can use this information to monitor status changes of VTAM resources. By being aware of status changes, PPOPROC can be the primary source of decisions controlling automated reaction to events that occur within the network.

PPOPROC has four possible sources of information:

• The VTAM PPO interface that delivers both unsolicited VTAM-generated messages and optional, solicited messages from VTAM commands issued at system consoles

  This source depends on the VTAM PPOLOG initialization parameter.

• Copies of commands and command responses resulting from operator activity
• Messages delivered to PPOPROC from &PPOALERT statements issued by another NCL process

  This facility generates test messages, and delivers them to PPOPROC for development and testing. The facility also lets you generate a new PPO message with more or less information than the original.

• PPOPROC-related messages of the three preceding types routed from remote regions across the Inter-System Routing (ISR) facility

PPOPROC messages from these sources can be used to report network resource status changes to a central point. The change can be unexpected (in which case VTAM reports the event as an unsolicited message) or in response to an operator command.

Centralization can be achieved by routing all relevant PPO messages to a central region. Several ISR options are used to facilitate this centralization.

You set up the central region for monitoring PPO messages with the ISR ENABLE=PPO UNSOLICIT=INBOUND command. This setup allows the region to receive PPO messages from remote regions. The remote regions specify ISR ENABLE=PPO UNSOL=OUTBOUND to enable delivery of messages to the central PPO processing link.