Chapter 11 Configuring Snmp; About Snmp - Cisco 4215 - Intrusion Detection Sys Sensor Configuration Manual

Configuring SNMP
This chapter describes how to configure SNMP. It contains the following sections:
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About SNMP

SNMP is an application layer protocol that facilitates the exchange of management information between
network devices. SNMP enables network administrators to manage network performance, find and solve
network problems, and plan for network growth.
SNMP is a simple request/response protocol. The network-management system issues a request, and
managed devices return responses. This behavior is implemented by using one of four protocol
operations: Get, GetNext, Set, and Trap.
You can configure the sensor for monitoring by SNMP. SNMP defines a standard way for network
management stations to monitor the health and status of many types of devices, including switches,
routers, and sensors.
You can configure the sensor to send SNMP traps. SNMP traps enable an agent to notify the management
station of significant events by way of an unsolicited SNMP message.
Trap-directed notification has the following advantage—if a manager is responsible for a large number
of devices, and each device has a large number of objects, it is impractical to poll or request information
from every object on every device. The solution is for each agent on the managed device to notify the
manager without solicitation. It does this by sending a message known as a trap of the event.
After receiving the event, the manager displays it and can take an action based on the event. For instance,
the manager can poll the agent directly, or poll other associated device agents to get a better
understanding of the event.
Trap-directed notification results in substantial savings of network and agent resources by eliminating
Note
frivolous SNMP requests. However, it is not possible to totally eliminate SNMP polling. SNMP requests
are required for discovery and topology changes. In addition, a managed device agent cannot send a trap
if the device has had a catastrophic outage.
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About SNMP, page 11-1
Configuring SNMP, page 11-2
Configuring SNMP Traps, page 11-4
Supported MIBS, page 11-6
Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 5.0
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