Extreme Networks EPICenter Guide Manual page 58

Getting Started with EPICenter
Sample Type: The sample value (a percentage) is always an absolute value
●
Startup Alarm: The Startup condition is predefined to be Rising
●
NOTE
To define an alarm for a CPU Utilization threshold event, select SNMP Trap as the Event Type, then select CPU
Utilization Rising Threshold or CPU Utilization Falling Threshold as the Event Name.
If you define an alarm for a CPU Utilization Rising Threshold event, an alarm will be generated each
time the sample value meets the following conditions:
When the sample value becomes greater than or equal to the Rising Threshold for the first time
■
(including the initial sample) after the alarm is enabled.
The first time the sample value becomes greater than or equal to the Rising Threshold, after
■
having become less than or equal to the Falling Threshold (80% of the Rising threshold).
If you define an alarm for CPU Utilization Falling Threshold events, an event will be generated each
time the sample value meets the following conditions:
The first time the sample value becomes less than or equal to 80% of the Rising Threshold, after
■
having become greater than or equal to the Rising Threshold.
It is important to understand that, except for the initial occurrence of a Rising Threshold alarm, a CPU
Utilization alarm will be generated only the when the sample value of the variable crosses the target
threshold for the first time after having crossed the other threshold.
The diagram shown in
configured a CPU Utilization rising threshold. The startup condition for a CPU Utilization event is
always predefined to be Rising.
CPU Utilization Event Generation
Figure 23: CPU Utilization event generation
Sampled
CPU
utilization
value
Rising
threshold
Falling
threshold
(90% of
rising)
= alarm event generated
The first CPU Utilization trap occurs at the initial sample value, since the value is above the CPU
Utilization Rising threshold. If the initial value were below the Rising threshold, no event would occur.
58
Figure 23 illustrates how CPU Utilization trap events will occur once you have
Initial
sample
value
B
A
X
Time (sample intervals)
C
Z
Y
XM_023
EPICenter Concepts and Solutions Guide