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New Member

Input errors

HI all,

We have lots of input errors in a gigabyte interface and we are looking for the reason. Here is the sh inter output:

GigabitEthernet2/1 is up, line protocol is up (connected)

Hardware is C6k 1000Mb 802.3, address is 0015.c674.5b80 (bia 0015.c674.5b80)

Description: "P-PE"

Internet address is

MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec,

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

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 1000Mb/s, media type is SX

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

Clock mode is auto

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

Last input 00:00:00, output 00:00:01, output hang never

Last clearing of "show interface" counters 00:18:20

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

Queueing strategy: fifo

Packet Drop strategy: random early detection (DWRED)

Output queue: 0/40 (size/max)

5 minute input rate 76000 bits/sec, 45 packets/sec

5 minute output rate 22000 bits/sec, 19 packets/sec

L2 Switched: ucast: 199 pkt, 14080 bytes - mcast: 374 pkt, 32954 bytes

L3 in Switched: ucast: 50174 pkt, 9727105 bytes - mcast: 38 pkt, 3648 bytes mcast

L3 out Switched: ucast: 29077 pkt, 11880607 bytes mcast: 343 pkt, 32184 bytes

50313 packets input, 9646908 bytes, 0 no buffer

Received 481 broadcasts (36 IP multicast)

0 runts, 0 giants, 0 throttles

1046 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 0 multicast, 0 pause input

0 input packets with dribble condition detected

29517 packets output, 11668390 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

There are no runts, giants..... has anyone idea about where is the issue?

Thx a lot in advance.



Re: Input errors

Hola Enrique,

since the 'input error' counter includes runts, giants, no buffer, CRC, frame, overrun, and ignored counts, and since you do not see any of those, chances are that you are experiencing physical problems. If possible, try to swap the cable, or try another Gigabit port, to see if the input errors disappear...




Re: Input errors

In additional to GNT's post, it may also be the connected device NIC failure. Try to swap the easiest item at first then one-by-one. e.g. cable, GE prot then NIC.

Hope this helps.

New Member

Re: Input errors


Thx a lot for the two responses ;)

Really helpful!



Re: Input errors

You're welcome. Does it solve the problem ? :)

New Member

Re: Input errors

Not for the moment :) I mean... the two devices involved in this issue are critical, I'm waiting for a window time in order to check it.

I'll post the results.