C2651 Unknown Protocol Drops

ldengming · ‎08-17-2013

Please help and advise. I am unable to connect any device on both my fa0/0 and fa0/1. Is it a hardware failure?

FastEthernet0/0 is up, line protocol is up

Hardware is AmdFE, address is 0013.7f8e.3660 (bia 0013.7f8e.3660)

Internet address is 192.168.1.1/24

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

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

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 100Mb/s, 100BaseTX/FX

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

Last input 00:00:02, output 00:00:02, output hang never

Last clearing of "show interface" counters 00:44:24

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 0 bits/sec, 0 packets/sec

5 minute output rate 0 bits/sec, 0 packets/sec

2112 packets input, 429469 bytes

Received 2112 broadcasts, 0 runts, 0 giants, 0 throttles

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

0 watchdog

0 input packets with dribble condition detected

315 packets output, 32310 bytes, 0 underruns

0 output errors, 0 collisions, 0 interface resets

2105 unknown protocol drops

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out

Reza Sharifi · ‎08-17-2013

Have a look at this post with the same issue:

https://supportforums.cisco.com/thread/139568

HTH

ldengming · ‎08-17-2013

My packets are entirely dropped including ICMP Echo and ARP not just DTP, CDP packets.

6142 packets input, 1255543 bytes

Received 6142 broadcasts, 0 runts, 0 giants, 0 throttles

6124 unknown protocol drops

I directly connected a laptop to the port and ping but the pings were dropped as well.

Reza Sharifi · ‎08-17-2013

Can you post "sh run" from the router?

ldengming · ‎08-17-2013

Thanks Reza. For your reference

Current configuration : 1216 bytes

!

version 12.4

service timestamps debug datetime msec

service timestamps log datetime msec

no service password-encryption

!

hostname

!

boot-start-marker

boot-end-marker

!

enable secret 5

enable password

!

no aaa new-model

memory-size iomem 30

clock save interval 8

no network-clock-participate slot 1

no network-clock-participate wic 0

ip cef

!

no ip domain lookup

!

multilink bundle-name authenticated

!

archive

log config

hidekeys

!

interface FastEthernet0/0

ip address 10.0.1.3 255.255.255.0

duplex auto

speed auto

no mop enabled

!

interface Serial0/0

no ip address

shutdown

!

interface FastEthernet0/1

no ip address

shutdown

duplex auto

speed auto

!

interface Serial0/1

no ip address

shutdown

!

ip forward-protocol nd

!

no ip http server

no ip http secure-server

!

control-plane

!

line con 0

exec-timeout 0 0

password

logging synchronous

login

speed 115200

line aux 0

line vty 0 4

exec-timeout 0 0

password

logging synchronous

login

line vty 5 15

exec-timeout 0 0

password

logging synchronous

login

!

end

Reza Sharifi · ‎08-17-2013

On your first post you have:

Internet address is 192.168.1.1/24

On your last post you have:

interface FastEthernet0/0

ip address 10.0.1.3 255.255.255.0

are these both from the same router?

If yes, try this command

interface FastEthernet0/0

mop enabled

and test again

HTH

ldengming · ‎08-21-2013

Thanks but I found an anomaly that suggests its a main board issues.

I debug arp and saw the ping address alway show incomplete. I used wireshark to capture the ping packet and found 2 of the bits always set as 1.

For broadcast to 0000.0000.0000, the packet destination is 0002.0000.0002. I tried to key in static arp entry and observed the following:

For mac target 4F6D became 4F6F but 4F6B is correctly transmitted. I think the 2nd least significant bit of the 4th hex value is always 1.

Likewise if mac end with A, its transmitted correctly but 0 changes to 2 and 9 become B. Hence, the 2nd bit in the last hex is again always 1.

Unfortunately I think my router is defective. Repair is probably not worth it.