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Community Member

CRC errors on switch port

reliability of gig port of layer 3 switch is 249 and there are CRC errors on the link . tried changing the ports but no solution. what can be the problem and kindly suggest some solution.

sh int is attached herewith.......

GigabitEthernet1/0/1 is up, line protocol is up (connected)

Hardware is Gigabit Ethernet, address is 0013.1a91.9401 (bia 0013.1a91.9401)

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,

reliability 249/255, txload 1/255, rxload 1/255

Encapsulation ARPA, loopback not set

Keepalive not set

Full-duplex, 100Mb/s, media type is 10/100/1000BaseTX SFP

input flow-control is off, output flow-control is unsupported

ARP type: ARPA, ARP Timeout 04:00:00

Last input 00:00:00, output 00:00:13, output hang never

Last clearing of "show interface" counters 01:14:34

Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0

Queueing strategy: fifo

Output queue: 0/40 (size/max)

5 minute input rate 124000 bits/sec, 109 packets/sec

5 minute output rate 58000 bits/sec, 5 packets/sec

411048 packets input, 82702630 bytes, 0 no buffer

Received 354522 broadcasts (0 multicast)

0 runts, 0 giants, 0 throttles

12303 input errors, 5101 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 89607 multicast, 0 pause input

0 input packets with dribble condition detected

57360 packets output, 16181784 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 PAUSE output

0 output buffer failures, 0 output buffers swapped out


Re: CRC errors on switch port


Which device is this port connecting to?

It's running at 100Mbps/Full-Duplex. Properly be a fiber port.

You may check the cable and duplex on both sides.



Community Member

Re: CRC errors on switch port

The most common cause for CRC errors on a switch port is a duplex mismatch. The other end is probably set to auto or perhaps even half. If both ends are set to full the CRC errors will usually stop. Otherwise there may be a cabling or hardware problem

Community Member

Re: CRC errors on switch port

i have found a duplex mismatch on trunk port , but i am not able to convert it to full duplex. port goes down as i try to do it.

Also , i am not getting errors on this port . some other port is generating CRC errors.

any solution ???

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