R3166-R3206-HP High-End Firewalls System Management and Maintenance Configuration Guide-6PW101

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limitation, may not cover all MIB information but four groups of information, alarm, event, history,
and statistics, in most cases.
The HP device adopts the second way and realizes the RMON agent function. With the RMON agent
function, the management device can monitor all the traffic flowing among the managed devices on all
connected LAN segments; obtain information about error statistics and performance statistics for network
management.
RMON groups
Among the RMON groups defined by RMON specifications (RFC 2819), the device has realized the
statistics group, history group, event group, and alarm group supported by the public MIB. Besides, HP
also defines and implements the private alarm group, which enhances the functions of the alarm group.
This section describes the five kinds of groups in general.
Ethernet statistics group
The statistics group defines that the system collects statistics on various traffic information on an interface
(at present, only Ethernet interfaces are supported) and saves the statistics in the Ethernet statistics table
(ethernetStatsTable) for query convenience of the management device. It provides statistics about network
collisions, CRC alignment errors, undersize/oversize packets, broadcasts, multicasts, bytes received,
packets received, and so on.
After the creation of a statistics entry on an interface, the statistics group starts to collect traffic statistics
on the interface. The result of the statistics is a cumulative sum.
History group
The history group defines that the system periodically collects statistics on traffic information at an
interface and saves the statistics in the history record table (ethernetHistoryTable) for query convenience
of the management device. The statistics data includes bandwidth utilization, number of error packets,
and total number of packets.
A history group collects statistics on packets received on the interface during each period, which can be
configured through the CLI.
Event group
The event group defines event indexes and controls the generation and notifications of the events
triggered by the alarms defined in the alarm group and the private alarm group. The events can be
handled in one of the following ways:
• Log—Logging event related information (the occurred events, contents of the event, and so on) in the
event log table of the RMON MIB of the device, and thus the management device can check the
logs through the SNMP Get operation.
• Trap—Sending a trap to notify the occurrence of this event to the network management station
(NMS).
• Log-Trap—Logging event information in the event log table and sending a trap to the NMS.
• None—No action
Alarm group
The RMON alarm group monitors specified alarm variables, such as total number of received packets
(etherStatsPkts) on an interface. After you define an alarm entry the system gets the value of the
monitored alarm variable at the specified interval, when the value of the monitored variable is greater
than or equal to the upper threshold, an upper event is triggered; when the value of the monitored