H3C Technologies H3C S3100 Series Switches - Manual (Page 457)

Operation Manual – SNMP and RMON
H3C S3100-52P Ethernet Switch Chapter 2 RMON Configuration
2-2
the RMON probe function. Through the RMON-capable SNMP agents running on the
Ethernet switch, an NMS can obtain the information about the total traffic, error
statistics and performance statistics of the network segments to which the ports of the
managed network devices are connected. Thus, the NMS can further manage the
networks.
2.1.2 Commonly Used RMON Groups
I. Event group
Event group is used to define the indexes of events and the processing methods of the
events. The events defined in an event group are mainly used by entries in the alarm
group and extended alarm group to trigger alarms.
You can specify a network device to act in one of the following ways in response to an
event:
z
Logging the event
z
Sending trap messages to the NMS
z
Logging the event and sending trap messages to the NMS
z
No processing
II. Alarm group
RMON alarm management enables monitoring on specific alarm variables (such as the
statistics of a port). When the value of a monitored variable exceeds the threshold, an
alarm event is generated, which triggers the network device to act in the preset way.
Events are defined in event groups.
With an alarm entry defined in an alarm group, a network device performs the following
operations accordingly:
z
Sampling the defined alarm variables periodically
z
Comparing the samples with the threshold and triggering the corresponding
events if the former exceed the latter
III. Extended alarm group
With extended alarm entry, you can perform operations on the samples of alarm
variables and then compare the operation results with the thresholds, thus implement
more flexible alarm functions.
With an extended alarm entry defined in an extended alarm group, the network devices
perform the following operations accordingly:
z
Sampling the alarm variables referenced in the defined extended alarm
expressions periodically
z
Performing operations on the samples according to the defined expressions
z
Comparing the operation results with the thresholds and triggering corresponding
events if the operation result exceeds the thresholds.