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1 the snmp utilities, 6 the mib compiler – Compaq AAR04BCTE User Manual

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Overview

1.5 The eSNMP API

Interface routines handle the basic subagent operations, such as:

Subagent initialization and termination

Registration

Polling of the master agent

Trap sending

UNIX system time conversion

Adding and removing subagent capabilities registered with the master agent

The support routines allow the subagent to manipulate the data in the response
to the request, and include the following:

Basic protocol data unit (PDU) handling

Authentication handling

Octet string handling

Variable binding (

VARBIND

) handling

Object identifier (OID) handling

Buffer handling

Chapter 5 describes the API routines in more detail.

To create a subagent, the programmer must provide modules to implement the
method routines, as described in Chapter 3.

1.5.1 The SNMP Utilities

To provide quick access to information in the MIBs, and to test SNMP operation,
TCP/IP Services provides the following utilities:

TCPIP$SNMP_REQUEST.EXE, a MIB browser that allows you to retrieve
and update objects from the MIBs.

TCPIP$SNMP_TRPSND.EXE, a trap sender that generates traps (messages
that require no response).

TCPIP$SNMP_TRPRCV.EXE, a trap receiver (or ‘‘listener’’) that is used to
detect trap messages.

For information about using the SNMP utilities, see Chapter 4.

1.6 The MIB Compiler

The MIB compiler processes the statements in an ASN.1 file and generates
modules that are used by the developer to create subagent routines. For every
ASN.1 input file that is processed using the MIB compiler, two output files, a
subtree_TBL.H file and a subtree_TBL.C file, are generated, where subtree is the
name from the original MIB definition file (for example, chess). The output files
are described in more detail in Chapter 3.

The subtree_TBL.H file is a header file that contains the following:

A declaration of the subtree structure

Index definitions for each MIB variable in the subtree

Enumeration definitions for MIB variables with enumerated values

MIB group data structure definitions

Overview 1–7