How to resolve CRC errors


How to resolve CRC errors

Use below command to check CRC errors in CICO IOS.

Command :- show interfaces fastEthernet x counters errors

CRC errors
CRC errors

Command :- show interfaces fastEthernet x 

CRC errors
CRC errors

CRC errors are mainly Layer-1 issues, for layer 1 issue check following physical connectivity:-

1- When one site of a link is configured on full-duplex and the other on half-duplex you will see the CRC errors at the interface which is configured on full-duplex.

This problem occurs also when one site of a link is configured on auto-duplex and the other fixed (full-duplex).

insure that speed and duplex setting are same at both the ends.

2- Check cables to determine whether any are damaged, if damaged, change the cable connecting between these ports.

4- If you are using 100BaseTX, make sure you that you are using Category 5 cabling and not another type, such as Category 3.

5- Monitor the level of frame errors over time. If they are increasing, try swapping interfaces and or ports to identify the problem.

6- Clear the counters then, shut and unshut the ports.

For more information follow below link.



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