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New Member

falsecarrierduringidle errors incrementing on one of my LANs

I can't find out specifically what this error is and was wondering if anyone knows the details of this error for certain. Thanks Much

2 REPLIES
Cisco Employee

Re: falsecarrierduringidle errors incrementing on one of my LANs

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.

New Member

Re: falsecarrierduringidle errors incrementing on one of my LANs

Thanks Much. That would add up.

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