- Ports and Health Sensors relating to those Ports are not associated. If a port has is ignored/alarming disabled, an alarm can still be generated by one of the sensors monitoring that same port. For example, an SFP switch port, with a transceiver plugged in still, is administratively enabled, but link is down. By ignoring the port, no port status alarms are generated. However, the ‘Transceiver Voltage’ would be 0 (zero) because the transceiver isn't doing anything. This would generate a ‘Sensor under limit’ alarm on the Sensor that is checking the Port, but not the port itself. The two-step solution to this would be, 1) Disable alarming on the sensor itself under the health settings to prevent further alarming, then 2) (if you don't want to see red widgets on the device's summary page) remove the discovery-generated threshold values on the sensor. By leaving the four threshold settings blank (null), Libre doesn't have a range of thresholds at all - “any” value is technically within spec because the acceptable range is “any numeric value”.