Distributed Systems Network Management (DSNM) Subsystem Interface Development Guide

Distributed Systems Network Management (DSNM) Subsystem Interface Development
Guide—109759 4-1
4
DSNM Command Requirements
Scope of This Section
This section defines the requirements for carrying out DSNM operations. It specifies
what information is sent to the command thread and what information must be returned
for each command so that the frame can create a DSNM-formatted response to return to
the requester.
Command Flow
The typical flow for a DSNM command is from a user to the DSNM command server,
and then to one or more I processes. Command responses flow back from the
I processes through the command server and then to the user.
The command server is responsible for resolving objects of a command, which means
determining their complete set of characteristics and routing them to the correct
I process. The I process is responsible for direct communication with the subsystem to
carry out commands delivered to it by the command server.
The general command processing flow is as follows:
•
The I process carries out the DSNM command for each input list object using
subsystem commands. Several subsystem commands may be required to carry out
one DSNM command. Input list objects are processed in the order they appear.
•
Carrying out a command for an object means executing it for some selection of the
input list object and its subordinates in the subsystem hierarchy. The exact set of
objects involved is determined by the combination of the hierarchy and state
modifiers (see “Object List Modifiers” on page 4-3).
•
The I process generates output objects as required by the command. Informational
commands other than AGGREGATE return an output object for each object. State-
change commands return an output object only in the case of errors. The
AGGREGATE command returns summary information rather than information
about individual objects.
Command Components
For each DSNM command, the frame places the following components in the command
thread context space:
•
The action to be performed
•
The command modifiers
•
A list of objects on which the operation is to be performed