OSI/AS Management Programming Manual

OSI/AS Subsystem Architecture
Introduction
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Event-Management
Interface
Event messages from OSI/AS are made available to management applications by the
Event Management Service (EMS). EMS collects, logs, and distributes event messages
that provide information to help you monitor the network environment, analyze
failures, and recognize and handle critical problems.
Figure 1-3 illustrates the event-management interfaces to OSI/AS and related
subsystems. The following steps summarize the activities shown in the figure:
1. An event occurs in the subsystem environment.
2. A subsystem process (in the OSI/AS environment, this could be a TAPS, TSP,
NSP, or OSI manager process) reports the event by sending an event message,
formatted as an SPI buffer, to the local EMS collector. Note that these processes
send event messages directly to the collector, not through SCP.
3. The collector stores the event message in a disk file called the event log.
4. If a forwarding distributor is present, this distributor forwards the event message
to a collector on a remote node. The remote collector stores the message in an
event log on its own node, so that the message exists on both nodes.
5. An application installs an EMS filter specifying the selection of event messages it
wants to receive. (Filters are optional, but recommended. If no filter is installed,
all event messages will be delivered to the application.)
6. The application can then open an EMS consumer distributor and request an event
message.
7. The distributor reads the log and returns to the application the next event message
that satisfies the conditions of the filter.
8. The application can present the message to the operator or take action itself.