EMS Manual

EMS Components and Architecture
EMS Manual—426909-005
2-5
Flow of Event Messages
Flow of Event Messages
Two types of EMS processes manage the flow of event messages from the subsystem
environment to the operations environment:

Event Message Collectors accept event messages from subsystems and log them.
Pre-log filtration (PLF) lets a primary or alternate collector use one or more filters to
detect and discard all event bursts with specified attributes or specific unwanted
events that would otherwise be sent to the collector’s log file.

Event Message Distributors filter event messages and return selected messages to
the operations environment.
Figure 2-1
shows the flow of event messages in a system:
1. Messages originate in the subsystems.
2. The subsystems send the messages to the primary and alternate collector
processes.
3. Collectors write passed event messages to the log files.
4. Distributors retrieve selected messages from the log files and send them to
processes, printers, terminals, and other destinations in the operations
environment.
The four kinds of distributors are each suited to a particular set of destination
requirements:

Forwarding

Consumer

Printing

Compatibility