SNMP Subagent Programmer's Guide

SNMP Subagent Programmer’s Guide—119728 3-1
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Writing and Compiling MIBs
This section describes how to encode Management Information Bases (MIBs) and how
to compile them using the MIB compiler, GDMOC (Guideline for Definition of
Managed Objects Compiler).
Encoding MIBs
When you use SNMP, you define a MIB to model the information your subagent makes
available for management. The manager views managed information as modeled in the
MIB.
To create a MIB, you write a MIB definition. The MIB definition models each object
managed by your subagent source code and each trap your subagent generates. In
SNMP terminology, a managed object is called a “MIB object.” The MIB definition
describes how your MIB objects are to be viewed from an SNMP manager perspective;
it is independent of how you implement variables for MIB object values in your
subagent.
To write a MIB definition, you use an extended version of the standard SNMP concise
MIB conventions described in RFC 1155 and RFC 1212. For traps, you use the standard
conventions described in RFC 1215. This subsection describes all the extensions in
detail, and summarizes the standard syntax; extensions are highlighted in bold type.
Refer to the RFCs for complete information about the standard components of MIB
definitions.
A MIB definition has several components.
MIB-definition-name
is a name you assign to your MIB definition.
snmp-type-definitions
map the standard SNMP data types of your MIB objects to C data types. More
information on this topic appears later in this section, under “SNMP Type
Definitions.”
object-name-definitions
uniquely identify your MIB in the SNMP name hierarchy. Encoding conventions
appear later in this section, under “Object Name Definitions.”
MIB-definition-name DEFINITIONS ::= BEGIN
snmp-type-definitions
object-name-definitions
MIB-object-definitions
[trap-definitions]
END