Distributed Systems Network Management (DSNM) Subsystem Interface Development Guide

The Management Services Layer
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109759—Distributed Systems Network Management (DSNM) Subsystem Interface
Development Guide
Overview of DSNM
The Management Services Layer
The management services layer performs services for the operations layer. It provides
for object resolution, the routing of commands to appropriate nodes and subsystems, and
the handling of event messages. Tandem's Distributed Systems Management (DSM)
services contribute object resolution and event management facilities. Figure 1-2
displays the DSNM and DSM functional connections.
DSM Components
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Distributed name service (DNS)
DNS is a subsystem that manages a distributed database of names, aliases, groups,
and composites of system and network objects. The DSNM command server
(discussed later in this subsection) communicates with the DNS name manager
process ($ZDNS) to resolve aliases, groups, and composite names into their
constituent subsystem-defined object names. DNS is described in the Distributed
Name Service (DNS) Management Operations Manual.
•
Event management service (EMS)
EMS provides event-collection, logging, and distribution facilities:
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The EMS collector process ($0) receives event messages from the processes that
control subsystem devices and writes them to an event log.
•
An EMS distributor process reads event messages from the event log, filters out
the messages for each DSNM-managed subsystem, and forwards them to the
appropriate event monitoring process (“E process,” discussed later in this
subsection). The locations of EMS filter files are defined to DSNM as part of
the installation procedure.
EMS is described in the EMS Manual.
DSNM Components
•
The command server process, which performs the following operations:
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Receives commands from server processes.
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Communicates with the DNS name manager process to resolve object names
into subsystem object names.
•
Sends command and object information to the interface process (I process)
associated with the targeted subsystem or to the object monitor process
(discussed next).
•
Collects response information from the I process or the object monitor process
and forwards it to the server process that initiated the command.