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m.stone 04-20-2010 01:40 AM

Interface Errors - CRC
My 4500 switch has CRC errors on the interface Te1/1 which is the uplink to the Core switch. It also has jabber and Sequence-Err.

SW#show interfaces tenGigabitEthernet 1/1
TenGigabitEthernet1/1 is up, line protocol is up (connected)
Hardware is Ten Gigabit Ethernet Port, address is 0021.55ee.f040 (bia 0021.55ee.f040)
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
reliability 253/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
Keepalive set (10 sec)
Full-duplex, 10Gb/s, link type is auto, media type is 10GBase-SR
input flow-control is on, output flow-control is off
ARP type: ARPA, ARP Timeout 04:00:00
Last input 00:00:00, output never, output hang never
Last clearing of "show interface" counters 1w3d
Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 2610000 bits/sec, 1014 packets/sec
5 minute output rate 928000 bits/sec, 73 packets/sec
402999837 packets input, 109603081226 bytes, 0 no buffer
Received 121951871 broadcasts (109766431 multicasts)
0 runts, 0 giants, 0 throttles
7630063 input errors, 7620231 CRC, 0 frame, 0 overrun, 0 ignored
0 input packets with dribble condition detected
56449307 packets output, 74896446971 bytes, 0 underruns
0 output errors, 0 collisions, 0 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out

SW#show int tenGigabitEthernet 1/1 counters errors
Port CrcAlign-Err Dropped-Bad-Pkts Collisions Symbol-Err
Te1/1 7620713 0 0 6692301

Port Undersize Oversize Fragments Jabbers
Te1/1 0 0 0 9832

Port Single-Col Multi-Col Late-Col Excess-Col
Te1/1 0 0 0 0

Port Deferred-Col False-Car Carri-Sen Sequence-Err
Te1/1 0 0 0 12129023

How can I fix this error?

ashley 04-22-2010 03:32 AM

Re: Interface Errors - CRC
Clear the interface counter and start with changing the fiber patch between the 2 switches. If that does not help then replace the GBICs and see what happens.

Hope to help.

David.C 04-22-2010 09:52 PM

Re: Interface Errors - CRC
The interface has had 7630063 'Input errors'. An input error includes runts, giants, no buffer, CRC, frame, overrun, and ignored counts. Other input-related errors can also cause the input error count to be increased. Some datagrams can have more than one error. Therefore, this sum may not be equal to the sum of enumerated input error counts.

The CRC error rate is 1.85579% (greater than 1 in a million packets), and the collision rate is less than 0.1%. This can indicate excessive noise or transmission problems on the LAN or the LAN bus itself. A high number of CRCs is usually the result of collisions or a station transmitting bad data.

Do the following things and check the results:-

Check cables to determine whether any are damaged. If 100BaseTX is being used, ensure Category 5 cabling is being used and not another type, such as Category 3.

Chris 04-26-2010 10:16 PM

Re: Interface Errors - CRC

At suggest I will go with suggestion provided by Ganesh and Reza that cable to be swapped.. other than that couple of unusal things i observed
  1. Received 121951871 broadcasts (109766431 multicasts)
  2. reliability 253/255, txload 1/255, rxload 1/255
Usually reliability in LAN always 255/255 and if you are not using any DHCP or HSRP then number of broadcast and multicast should be minimum. Packet sniffer with provide you more details why so many broadcasts and multicast..

Hope this will help you to progress towards resolution.

m.stone 04-29-2010 12:17 AM

Re: Interface Errors - CRC
Thanks Guys,

I am using fibre cables on that port, I will try changing the fibre patch cords.
And yes, I do see similar errors on the ports connected to the Core Switch.

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