NET/MASTER Network Control Language (NCL) Programmer's Guide

Overview of System-Level NCL Procedures
Developing System-Level NCL Procedures
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Overview of System-
Level NCL Procedures
A system-level procedure is an NCL procedure that has access to distinct types of
message flows within NonStop NET/MASTER MS, using certain verbs. There are two
main system-level NCL procedures: EMSPROC and LOGPROC. In addition,
MSGPROC NCL procedures are regarded as system-level procedures.
The EMSPROC NCL
Procedure
The function of the EMSPROC NCL procedure is to intercept and process EMS
messages received by NonStop NET/MASTER MS from the associated EMS
distributor. The EMSPROC NCL procedure runs under the control of the Event
Management Service Process (EMSP) virtual user.
When started, the associated EMS distributor sends all EMS events that pass its filter
to NonStop NET/MASTER MS. These messages are passed to EMSPROC (if it exists).
EMSPROC also receives EMS messages, PPO messages, and communications network
management (CNM) messages from Inter-System Routing (ISR).
Note The EMSDIST command starts or stops the receiving of events from an EMS event distributor. If a user is
allowed to receive EMS messages, the PROFILE EMS command determines whether messages are
displayed on a user’s OCS screen. The EMSCOLL command starts or stops the recording of events from
NonStop NET/MASTER MS to the EMS event collector. These commands are discussed in the NonStop
NET/MASTER MS Command Reference Manual.
Only one EMSPROC NCL procedure can operate at a time in a NonStop
NET/MASTER MS system. Accordingly, EMSPROC can act as a central intelligence
point to monitor events received by NonStop NET/MASTER MS. The procedure can
observe and react to unusual or critical conditions, and provide a platform for
automatic recovery action.
Defining an EMSPROC NCL Procedure
The SYSPARMS EMSPROC command is used to specify the name of a new EMSPROC
NCL procedure and to flush an existing EMSPROC NCL procedure. When defining a
new EMSPROC, the name you specify does not have to be EMSPROC; if it is not
EMSPROC, however, it is still referred to as EMSPROC or as an EMSPROC procedure.
The following command defines an EMSPROC procedure called EMSPROCA:
SYSPARMS EMSPROC=EMSPROCA