Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 
Community Member

CRC errors on switch ports


I'm checking port stats on a switch. On several ports, I see some CRC and other errors. The error percentage is usually something like one error out of one thousand packets.   

Can this be considered normal? Should I worry about this?



Re: CRC errors on switch ports

A small number of errors are acceptable. Divide the number of errors by the number of packets, multiply by 100 and that will give you the actual percentage. Feel free to post that number. If it really is .1%, that is fine.Also check that the duplex is full and not half. That's typical of CRC errors.

Hope that helps.

Re: CRC errors on switch ports

CRC errors usually indicates noise or transmission problems on the LAN interface or the LAN itself. A high number of CRCs is usually the result of collisions but can also indicate a physical issue (such as cabling, bad interface or NIC) or a duplex mismatch or a station transmitting bad data.

You might be looking at old counters. As a best practice might worth clearing your interface counters and monitor the interface with fresh counters building up so you have any idea of when the CRC counter start bulding up.

Good luck.

CreatePlease to create content