Outside CRC Error, what does this mean?

amranjunid · ‎10-15-2005

Hi Guys,

Been checking my pix "show interface" and I notice that I get 487 input errors, 231 CRC, 0 frame, 0 overrun, 231 ignored. I've doen a clear interface and did the "show interface" again after a day and I notice those errors again on the ethernet0 outside.

What does that mean? I asked a friend and he told me it is very likely that the cable connecting my pix from the IDC router is faulty thus causing that kind of errors, he advise me to get the IDC to change the cable. Want to hear a second opinion before I start talking to the IDC, don't want the engineer there to tell me it is not their fault. :) Thanks in advance.

interface ethernet0 "outside" is up, line protocol is up

Hardware is i82559 ethernet, address is 0014.a807.610c

IP address 203.81.56.36, subnet mask 255.255.255.224

MTU 1500 bytes, BW 100000 Kbit full duplex

884883 packets input, 855856783 bytes, 0 no buffer

Received 14232 broadcasts, 256 runts, 0 giants

487 input errors, 231 CRC, 0 frame, 0 overrun, 231 ignored, 0 abort

773316 packets output, 87428218 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collisions, 0 deferred

0 lost carrier, 0 no carrier

input queue (curr/max blocks): hardware (128/128) software (0/9)

output queue (curr/max blocks): hardware (3/9) software (0/1)

interface ethernet1 "inside" is up, line protocol is up

Hardware is i82559 ethernet, address is 0014.a807.610d

IP address 192.168.0.254, subnet mask 255.255.255.0

MTU 1500 bytes, BW 100000 Kbit full duplex

763163 packets input, 75827259 bytes, 0 no buffer

Received 29 broadcasts, 0 runts, 0 giants

0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

841162 packets output, 853068900 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

0 babbles, 0 late collisions, 0 deferred

0 lost carrier, 0 no carrier

input queue (curr/max blocks): hardware (128/128) software (0/8)

output queue (curr/max blocks): hardware (0/9) software (0/1)

jackko · ‎10-15-2005

crc basically is a mean for a device verifying the received data if there is any error during transmission.

according to cisco:

The number of Cyclical Redundancy Check errors. When a station sends a frame, it appends a CRC to the end of the frame. This CRC is generated from an algorithm based on the data in the frame. If the frame is altered between the source and destination, the security appliance notes that the CRC does not match. A high number of CRCs is usually the result of collisions or a station transmitting bad data.

i guess the issue is related to duplex mismatch between the pix and the outside interface connected device. also, verify the cable whether it's faulty or not.