3Com Switch 7750 Series
Command Reference Guide – SNMP & RMON Chapter 2 RMON Configuration Commands
2-14
Use the undo rmon prialarm command to remove a specified extended alarm entry.
The maximum number of distances in the table depends on the hardware resources.
Note:
z Before adding an extended alarm entry, you need to use the rmon event command
to define the events to be referenced by the entry.
z Make sure the node to be monitored exists before executing the rmon event
command.
z You can define up to 50 extended alarm entries.
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 (prialarm-formula) once in each period specified by the
sampling-timer argument.
z Performing operations on sampled values according to the defined extended
alarm expressions (prialarm-formula)
z Comparing the operation result with the set thresholds and perform corresponding
operations, as described in Table 2-8.
Table 2-8 Operation result and corresponding operation
Comparison Operation
The operation result is larger than or equal to the
set upper threshold (threshold-value1) Triggering the event identified
by the event-entry1 argument
The operation result is smaller than or equal to
the set lower threshold (threshold-value2) Triggering the event identified
by the event-entry2 argument
Example
# Add the extended alarm entry numbered 2 as follows:
z Perform operations on the corresponding alarm variables using the expression
((1.3.6.1.2.1.16.1.1.1.4.1)*100).
z Sampling interval: 10 seconds
z Upper threshold: 50
z Lower threshold: 5
z Event 1 is triggered when the change ratio is larger than the upper threshold.
z Event 2 is triggered when the change ratio is less than the lower threshold.
z The alarm entry is valid forever.
z Entry owner: user1