Rmon Configuration; Rmon Overview; Introduction; Working Mechanism - H3C S5820X Series Configuration Manual

8

RMON Configuration

This chapter includes these sections:

RMON Overview

Configuring the RMON Statistics Collection
Configuring the RMON Alarm Function
Displaying and Maintaining RMON
RMON Overview

Introduction

Remote Monitoring (RMON) is used to remotely monitor and manage devices on the network by
implementing such functions as statistics collection and alarm. The statistics collection function
enables a managed device to periodically or continuously track various traffic information on
the network segments that connect to its ports, such as total number of packets received or
total number of oversize packets received. The alarm function enables a managed device to
monitor the value of a specified MIB variable, log the event and send a trap to the management
device when the value reaches the threshold, such as the port rate reaches a certain value or
the potion of broadcast packets received in the total packets reaches a certain value.
Both the RMON protocol and the Simple Network Management Protocol (SNMP) are used for
remote network management:
Implemented on the basis of SNMP, RMON is an enhancement to SNMP. RMON sends
traps to the management device to notify the abnormality of the alarm variables by using
the SNMP trap sending mechanism. However, the trap function defined in SNMP is used to
notify the management device whether some functions on managed devices operate
normally and the change of physical status of interfaces. Traps in RMON and those in
SNMP have different monitored targets, triggering conditions, and report contents.
RMON provides an efficient means of monitoring subnets and allows SNMP to monitor
remote network devices in a more proactive and effective way. The RMON protocol defines
that when an alarm threshold is reached on a managed device, the managed device
automatically sends a trap to the management device, so the management device does not
need to get the values of MIB variables for multiple times and compare them, thus reducing
the traffic between the management device and the managed device. Large scale networks
can thus be managed easily and effectively.

Working Mechanism

RMON allows multiple monitoring devices (management devices). A monitor collects data in the
following two ways:
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