EMS Manual

Introduction to EMS
EMS Manual—426909-005
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EMS in the System Environment
EMS in the System Environment
EMS runs as a layer between the subsystem environment and the operations
environment:

In the subsystem environment, subsystem software directly controls resources
(such as communication lines, files, and processes). Subsystems can be HP
products such as Pathway, components of DSM such as ViewPoint, or user-written
programs.

In the operations environment, operations staff and specialized application
programs (known as management applications) obtain information needed to
manage the system or network.
In the requester-server model, EMS acts as a server to both layers. It responds to
requests from the subsystem layer to accept and log event information, and responds
to requests from the operations environment to retrieve certain event information as
needed.
Because events can occur at any time, a process that logs (or collects) events must
run continuously. This process, the primary collector ($0), is installed when the system
is generated. EMS allows only one primary collector on each node of a network.
In addition to the primary collector, you can define alternate collectors to provide
separate logging facilities for sorting selected events in separate log files. You can
define as many alternate collectors on a system as you want, and you can start or stop
them whenever you want.
You retrieve events from log files by running EMS processes called distributors. You
can initiate and terminate distributors as dictated by your operations environment
needs.
Figure 1-1
is a simplified diagram of the EMS layer, its components, and their
relationships to the subsystem and operations environments.