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New Member


Has anybody encountered this kind of error "bitErrRTThresExceeded" for a port (connected to a server/storage)?

When we bounce the port the port comes up "on" but again goes down after a while with the above error.

Any ideas?

New Member

Re: bitErrRTThresExceeded

Hi Pavan,

it is the indication of link error.

check for the port errors.

I had similar issue and cable replacement resolved it..

Good luck.


Cisco Employee

Re: bitErrRTThresExceeded

Agreed...could be cable. Also could be dirty patch panel (if there is one) or a faulty SFP on either end. I have also seen this with mismatched SFPs and cable type. IE, when you have 1310 nm SFPs with multi mode cable.

- Mike

New Member

Re: bitErrRTThresExceeded

patch cables.

things to do:

1. check to make sure all patch cables and seated correctly. unplug and replug in.

2. clean the cables ends if you have the "special" cleaner pads

3. if you have a fiber power lose meter (dB) you could check the cables with that.

4. replace the patch cord.

New Member

Re: bitErrRTThresExceeded

Thanks all for replying to this post.

However, I have verified each one of the components SFIPs/cables/patch panels,switch port etc. Although, the error is rare but it does comes on and off on various ports at times.

Do you guys think this error could also relate to the end devices/port cfg on the devices/data from the devices etc?

New Member

Re: bitErrRTThresExceeded

If you think you can live with it, you can configure the port to ignore them. There is a default setting (that you can't change) where if you get x amounts of errors in a 5 minute period, the port shuts down. You can just ignore them with the command:



switchport ignore bit-errors



I would keep an eye on the port through syslog (or perhaps SNMP traps if configured properly) as they will raise bit-error related messages even though you told the port to ignore them.

I have found the cables (including fobot ports/cables) to always be the problem here. Don't just fiddle with the cables, replace them. SFPs are not generally the cause of the problem and I have never seen a storage array front itself cause any problems.


New Member

Re: bitErrRTThresExceeded

the SFP could be failing. you might want to replace that and see if the problem still exists.

Cisco Employee



BitError Threshold Exceeded means that you had more than an acceptable number of incoming CRC errors in a short timespan on an interface.

This is usually indicative of a bad fiber, or a bad SFP (optics/gbic) on either side of the link.

you can get a good indication of the quality of the link with the following command:

# show interface fcX/Y transc det

where fcX/Y is replaced by the interface you want to check out

It will show you the min and max alert and alarm values, so you know what your actual value should fall between.