The DDM information and warnings and alarms are collected at one minute intervals, so the minimum resolution for any DDM events when correlating with other system events is one minute.
In the Transceiver Digital Diagnostic Monitoring section of the show port port-id detail command output:
if the present measured value is higher than either or both of the High Alarm and High Warn thresholds, an exclamation mark ‟!” displays along with the threshold value
if the present measured value is lower than either or both of the Low Alarm and Low Warn thresholds, an exclamation mark ‟!” displays along with the threshold value
B:SR7-101# show port 2/1/6 detail
......
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Transceiver Digital Diagnostic Monitoring (DDM), Internally Calibrated
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Value High Alarm High Warn Low Warn Low Alarm
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Temperature (C) +33.0+98.0 +88.0 -43.0-45.0
Supply Voltage (V) 3.31 4.12 3.60 3.00 2.80
Tx Bias Current (mA)5.7 60.0 50.00.1 0.0
Tx Output Power (dBm) -5.45 0.00 -2.00 -10.50 -12.50
Rx Optical Power (avg dBm) -0.65-3.00! -4.00! -19.51 -20.51
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