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Community Member

receive errors

Hi all, can anyone tell me why im getting receive errors on the uplink to my fiber switch ?



Re: receive errors

Not unless you can give us some more detail, diagnostic "show" commands, etc.

I will say, however, that some switches record vast numbers of symbol errors on fiber links, and these are artifacts of a bug. But in the absence of other information, that is only a guess.

Kevin Dorrell


Re: receive errors

What are the specific errors you are seeing?

One of the most common causes of errors is a duplex mismtch - the first thing to do is confirm that both ends are the same. If both are running at full, you should not be seeing any CRC or framing type errors.

Bear in mind that you need to check the operational state of the link, not just the config as one platform seems to be prone to dropping to autonegotiation even when configured!

If your duplex settings are correct at each end, the you need to look at the media - easiest frist check may be to replace your GBIC/SFP - I would try the end getting the RX errors first, then the other end. If you still get errors, you may need to try another fibre pair, or get the pair you are using metred to check if they are OK.

Oh, and make sure that all fibres are correct - I have seen instalaltions where it should be single mode, but a multimode patch has been used for example.

Community Member

Re: receive errors

Hi all, thanks for your help

I have basically seen this, from the switch in question I can ping the main distribution switch fine, when I try and ping the switch itself it takes longer, if I unplug the fiber to the distibution switch, the lights on the switch calm down, I have replaced both fibers at either end, moved port on the dist switch etc, and even replaced the switch, what could this be ? I have monitored the port and I cant see much traffic at all, could it be the fiber in between the 2 rooms that would cause this delay ? im getting between 20 and 80 ms ping times.

your help would be great



Re: receive errors

The main bulding fibre can be at fault, though as it tends not to be moved it is unusual. More likely is perhaps a bit if dust in a connector.

It would help us if you could attach a sh interface so we can see the errors, ideally one from each end.


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