Resetting statistical alarms
Statistical alarms (as opposed to filter-based alarms) maintain cumulative counts of various network statistics, triggering only once upon exceeding the threshold. Therefore, triggered (tripped) statistical alarms must be reset before they can trigger once again.
SNMP devices have a different method for resetting alarms.
To reset SNMP device alarm counters of a currently selected SNMP device:
On the Home tab, in the Probe group, click Setup > Reset SNMP Device Alarm Counters.
To reset SNMP device alarm counters for all SNMP devices:
On the Home tab, in the Probe group, click Setup > Reset All SNMP Device Alarm Counters.
 
To reset the counters and enable the alarms to once again trigger, click Alarm Settings at the bottom of the log window. Select the probe with the alarms you want to reset by clicking on the probe list, then click Reset Probe Alarms.