Reference Guide

26 Introduction
On supported operating systems, the SNMP master agent is provided with
the operating system. For example, on supported Microsoft Windows
operating systems, the Windows SNMP service is the SNMP master agent.
For information on the versions of the SNMP protocol supported by the
SNMP master agent, see the operating system documentation.
SNMP Extension Agent
The SNMP extension agent is responsible for registering the MIB objects that
it supports with the SNMP master agent and then processing requests from
the SNMP master agent for those MIB objects. The SNMP extension agent
also initiates event notifications to the SNMP master agent. The SNMP
extension agent does not receive or send standard SNMP protocol messages.
The SNMP extension agent communicates with the SNMP master agent using
an extension protocol defined by the SNMP master agent.
The Server Administrator SNMP subagent is an SNMP extension agent.
Managed Object
A managed object is any item in a computer system that can be singled out
for discovery, monitoring, or user intervention and correction.
NOTE: Not all managed objects described in this guide are supported by all systems.
MIB
A MIB acts as a structured road map for managed objects. As an Application
Programming Interface (API), a MIB allows systems management tools to
retrieve data maintained by an agent. The server administrator MIB is divided
into several major groups of managed objects.
Variable
A variable is a component of a managed object. A temperature probe, for
example, has a variable to describe its capabilities, its health or status,
and certain indexes that you can use to locate specific temperature probes.
One index for the probe would be the probe’s chassis number. Some systems
may have multiple chassis—one chassis for the central processing unit and
another chassis for storage. A chassis within a system can also have more than
one temperature probe. Variables for a temperature probe include its
capabilities, status, chassis index, and index.