H3C Technologies H3C WX6000 Series Access Controllers - Manual (Page 107)

9-3
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
variable is smaller than or equal to the lower threshold, a lower event is triggered. The event is then
handled as defined in the event group.
If the value of a sampled alarm variable overpasses the same threshold multiple times, only the first one
can cause an alarm event. That is, the rising alarm and falling alarm are alternate.
Private alarm group
The private alarm group calculates the values of alarm variables and compares the result with the
defined threshold, thereby realizing a more comprehensive alarming function.
The system handles the prialarm alarm table entry (as defined by the user) in the following ways:
z Periodically samples the prialarm alarm variables defined in the prialarm formula.
z Calculates the sampled values based on the prialarm formula.
z Compares the result with the defined threshold and generates an appropriate event.
If the count result overpasses the same threshold multiple times, only the first one can cause an alarm
event. That is, the rising alarm and falling alarm are alternate.
Configuring the RMON Statistics Collection Function
RMON statistics collection function can be implemented by either the Ethernet statistics group or the
history group, but the objects of the statistics are different, you can choose to configure a statistics
group or a history group accordingly.
z A statistics object of the Ethernet statistics group is a variable defined in the Ethernet statistics
table, and the recorded content is a cumulative sum of the variable from the time the statistics entry
is created to the current time. For more information, see Configuring the RMON Ethernet Statistics
Collection Function .
z A statistics object of the history group is the variable defined in the history record table, and the
recorded content is a cumulative sum of the variable in each period. For more information, see
Configuring the RMON History Statistics Collection Function .