beautypg.com

Configuring rmon, Overview, Rmon groups – H3C Technologies H3C MSR 5600 User Manual

Page 133: Statistics group, History group, Event group

background image

120

Configuring RMON

Overview

Remote Network Monitoring (RMON) is an enhancement to SNMP. It enables proactive remote

monitoring and management of network devices and subnets. An RMON monitor periodically or
continuously collects traffic statistics for the network attached to a port on the managed device. The

managed device can automatically send a notification when a statistic crosses an alarm threshold, so the

NMS does not need to constantly poll MIB variables and compare the results.
RMON uses SNMP notifications to notify NMSs of various alarm conditions such as broadcast traffic
threshold exceeded. In contrast, SNMP reports function and interface operating status changes such as

link up, link down, and module failure.
H3C devices provide an embedded RMON agent as the RMON monitor. An NMS can perform basic

SNMP operations to access the RMON MIB.

RMON groups

Among standard RMON groups, H3C implements the statistics group, history group, event group, alarm

group, probe configuration group, and user history group. H3C also implements a private alarm group,
which enhances the standard alarm group. The probe configuration group and user history group are

not configurable from the CLI. To configure these two groups, you must access the MIB. For more

information about MIB settings for RMON, see Comware V7 Platform MIB Companion.

Statistics group

The statistics group samples traffic statistics for monitored Ethernet interfaces and stores the statistics in
the Ethernet statistics table (ethernetStatsTable). The statistics include number of collisions, CRC

alignment errors, number of undersize or oversize packets, number of broadcasts, number of multicasts,

number of bytes received, and number of packets received.
The statistics in the Ethernet statistics table are cumulative sums.

History group

The history group periodically samples traffic statistics on interfaces and saves the history samples in the

history table (etherHistoryTable). The statistics include bandwidth utilization, number of error packets,

and total number of packets.
The history table stores traffic statistics collected for each sampling interval.

Event group

The event group controls the generation and notifications of events triggered by the alarms defined in the

alarm group and the private alarm group. The following are RMON alarm event handling methods:

Log—Logs event information (including event time and description) in the event log table so the
management device can get the logs through SNMP.

Trap—Sends an SNMP notification to notify an NMS of the event.

Log-Trap—Logs event information in the event log table and sends SNMP notifications to the NMS.

This manual is related to the following products: