Hi, Usually when Cyclic Redundancy Check (CRC) errors are incrementing in the show interface command output, it indicates that the cyclic redundancy checksum generated by the originating LAN/WAN device does not match the checksum calculated from the data received. On a LAN, this usually indicates noise or transmission problems on the LAN interface or cable. A high number of CRCs is usually the result of collisions or a station transmitting bad data.
So we can safely assume that CRCs are a very critical alarm and it can not be ignored so I don’t think there should be a threshold in general, the NMS should monitor interfaces for CRCs and if the number increments then an immediate check is needed, we are talking on the core links here. So we cant wait till the counter increments. Once we have CRCs, then we have a bad cable, port or router and this needs immediate attention. Regards, Kim On Wed, Feb 23, 2011 at 3:53 PM, Harold 'Buz' Dale <buz.d...@usg.edu> wrote: > First thing I would do would be to check for a duplex mismatch and then > check the wiring (either by replacing the cable if it's a simple patch or > using a cable tester over the span.) You might also just physically trace it > and see if someone decided to hang a fluorescent light off of it or > something too. > Luck, > Buz > > -----Original Message----- > From: cisco-nsp-boun...@puck.nether.net [mailto: > cisco-nsp-boun...@puck.nether.net] On Behalf Of alex nyagah > Sent: Wednesday, February 23, 2011 6:19 AM > To: cisco-nsp@puck.nether.net > Subject: [c-nsp] CRC Errors on Ethernet Router > > Hi All, > > I am noting CRC errors on my Ethernet port on my cisco router, what could > it > be causing it.. > > -- > ** > _______________________________________________ > cisco-nsp mailing list cisco-nsp@puck.nether.net > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > > _______________________________________________ > cisco-nsp mailing list cisco-nsp@puck.nether.net > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ > _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
