The NCP in a 3720, 3725, or 3745 communication controller sends alert messages to the VTAM® program whenever a serious or permanent error occurs in the communication controller.

The NCP sends hardware error records to the maintenance operator subsystem (MOSS). If the MOSS determines that they are permanent errors, it sends them back to the NCP, which forwards them to all owning host processors.

If a communication network management (CNM) application program, such as the NetView® program, is active and authorized to receive alert messages, VTAM forwards the alert messages to that program. Otherwise, VTAM sends a message to the operator's console.