Hi there,
This post describes the process of how to handle CRC errors. Please have a look below to find the solution.
Fault diagnostic
The switch is reporting a lot of CRC errors on some interfaces and some packets are lost due to this issue.
You can use display interface xxxx to check the CRC error statistics.
Solution
Most probably, the CRC issue is caused by the hardware part, as it is not a software issue. There are some reasons which can cause the CRC issue, such as the transceiver not being inserted tightly, the fiber or cable being twisted too much, the transceiver being unstable, or the hardware of this port being unstable on the switch.
To handle the CRC issue, the best way is to do the cross-test:
Firstly check the transceiver and fiber to see if they are tightly connected. You can plug out and plug in to test again.
move the transceiver to other ports on the switch; if the CRC still persists, it means that the CRC is related to the transceiver or fiber. If CRC disappears, it means that maybe the hardware of this port is unstable. We can find another good transceiver to test again if the CRC still happens even if we replace it with another good transceiver. In this case, we can replace the switch.
- after step 2, if the CRC still occurs even after moving to other ports, it means that this may be related to a transceiver issue. We can replace it with another good transceiver; if the CRC disappears, then it's related to the faulty transceiver.
CRC may be related to a peer device also in case that the transceiver is not connected to the peer switch tightly or the hardware of the port is unstable on the peer switch. We can find another good transceiver to test on the peer switch; if the CRC still happens even if we test with another good transceiver, we can say the hardware of this port is unstable.
This would be how to handle the CRC errors. Thanks for reading this post!
