falseCarrierDuringIdle counter incrementing indicated that the switch port
sensed/detected "carrier" signal (streams of pre-amble bits) on the line
during idle and was on the lookout for the start-of-frame byte. However, instead, it detected an signal (a bit pattern) which is not the ieee specified start-of-frame byte and this is "illegal" according to the ethernet standard. So,
the switch incremented falseCarrierDuringIdle counter by 1 for that particular
port.
Now, the cause of the problem is really the other side of the link and the probable causes are either a duplex mismatch, noise environment or a bad cable, bad NIC with duplex mismatch being the biggest suspect.
