3Com corebuilder 3500 Implementation Manual page 550

550 C 18: D
HAPTER EVICE
M
ONITORING
An alarm calculates the difference in counter values over a set time
interval and remembers the high and low values. When the value of a
counter exceeds a preset threshold, the alarm reports this occurrence.
Using Transcend Network Control Services or any other SNMP network
management application, you can assign alarms to monitor any counter,
gauge, timetick, or integer. See the documentation for your management
application for details about setting up alarms.
Setting Alarm Thresholds Thresholds determine when an alarm
reports that a counter has exceeded a certain value. You can set alarm
thresholds manually through the network, choosing any value for them
that is appropriate for your application. The network management
software monitors the counters and thresholds continually during normal
operations to provide data for later calibration.
Figure 97 shows a counter with thresholds set manually.
Figure 97 Manually Set Thresholds
Counter
User specified
You can associate an alarm with the high threshold, the low threshold, or
both. The actions that occur because of an alarm depend on the network
management application.
User specified
high threshold
low threshold
Time