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New Member

Bug in Cisco 837?

I had a cisco 837 with IOS 12.3(2)XC. The log always has the error message "Dec 9 14:58:45: %CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on Ethernet0

(not full duplex), with switch1 FastEthernet0/1 (full duplex)."

But there is no error message under my router e0 interface. I have to put "no cdp enable" in the E0 iterface to make this error message despair.

Do you think it is a bug?

router#sh ver

Cisco Internetwork Operating System Software

IOS (tm) C837 Software (C837-K9O3SY6-M), Version 12.3(2)XC, EARLY DEPLOYMENT REL


Synched to technology version 12.3(1.6)T

TAC Support:

Copyright (c) 1986-2003 by cisco Systems, Inc.

Compiled Thu 25-Sep-03 10:23 by ealyon

Image text-base: 0x800131E8, data-base: 0x80CCB0FC

ROM: System Bootstrap, Version 12.2(8r)YN, RELEASE SOFTWARE (fc1)

ROM: C837 Software (C837-K9O3SY6-M), Version 12.3(2)XC, EARLY DEPLOYMENT RELEASE


router uptime is 5 days, 11 hours, 32 minutes

System returned to ROM by power-on

System restarted at 07:09:38 NZDT Thu Dec 4 2003

System image file is "flash:c837-k9o3sy6-mz.123-2.XC.bin"

This product contains cryptographic features and is subject to United

States and local country laws governing import, export, transfer and

use. Delivery of Cisco cryptographic products does not imply

third-party authority to import, export, distribute or use encryption.

Importers, exporters, distributors and users are responsible for

compliance with U.S. and local country laws. By using this product you

agree to comply with applicable laws and regulations. If you are unable

to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

If you require further assistance please contact us by sending email to

CISCO C837 (MPC857DSL) processor (revision 0x400) with 31130K/1638K bytes of mem


Processor board ID AMB0739004N (3018440145), with hardware revision 0000

CPU rev number 7

Bridging software.

1 Ethernet/IEEE 802.3 interface(s)

4 FastEthernet/IEEE 802.3 interface(s)

1 ATM network interface(s)

128K bytes of non-volatile configuration memory.

12288K bytes of processor board System flash (Read/Write)

2048K bytes of processor board Web flash (Read/Write)

Configuration register is 0x2102

router##sh int e0

Ethernet0 is up, line protocol is up

Hardware is PQUICC Ethernet, address is 000d.bcbb.79b5 (bia 000d.bcbb.79b5)

Internet address is

MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec,

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

Encapsulation ARPA, loopback not set

Keepalive set (10 sec)

Full-duplex, 10Mb/s

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

Last input 00:00:15, output 00:00:03, output hang never

Last clearing of "show interface" counters 1d01h

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

Queueing strategy: fifo

Output queue: 0/100 (size/max)

5 minute input rate 2000 bits/sec, 4 packets/sec

5 minute output rate 2000 bits/sec, 3 packets/sec

1699329 packets input, 113088293 bytes, 0 no buffer

Received 20229 broadcasts, 0 runts, 0 giants, 0 throttles

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

0 input packets with dribble condition detected

1136280 packets output, 197462526 bytes, 0 underruns

0 output errors, 0 collisions, 1 interface resets

0 babbles, 0 late collision, 0 deferred

0 lost carrier, 0 no carrier

0 output buffer failures, 0 output buffers swapped out


router#sh run int e0

interface Ethernet0

ip address

no cdp enable



Re: Bug in Cisco 837?

What switch has been connected to this router. Is it a 3500 xl switch ? Is the switch inline power enabled ? What version of code do you run on that switch ?

VIP Purple

Re: Bug in Cisco 837?

Hello Kevin,

I guess you verified that whatever is connected to your Ethernet0 has matching duplex and speed settings.

There is a documented bug, here is what it says, not sure if that applies to you; I guess you verified that whatever is connected to your Ethernet0 has matching duplex and speed settings:

Catalyst WS-C3524-PWR-XL-EN running 12.0(5)WC3b with ISL trunk to another Catalyst or

Router on switch reboots may display

%CDP-4-DUPLEX_MISMATCH: duplex mismatch discovered on FastEthernet0/0.1 (not half duplex),

with Switch2 FastEthernet0/24 (half duplex).>

Typicaly seen when the devices are hardset to 100 MB / full duplex and are running CDP-v2


Configure the following command under the interface in question on the WS-C3524-PWR-XL


'no power inline never '



New Member

Re: Bug in Cisco 837?

Hi, GP

I think you are talking about bug CSCdx85015 for cisco 3524XL switch. My neighbor switch is cisco 2950. Do you think this bug will still apply to cisco 2950?

router#sh cdp nei det


Device ID: switch1

Entry address(es):

IP address:

Platform: cisco WS-C2950-24, Capabilities: Switch IGMP

Interface: Ethernet0, Port ID (outgoing port): FastEthernet0/1

Holdtime : 174 sec

Version :

Cisco Internetwork Operating System Software

IOS (tm) C2950 Software (C2950-I6Q4L2-M), Version 12.1(14)EA1a, RELEASE SOFTWARE


Copyright (c) 1986-2003 by cisco Systems, Inc.

Compiled Tue 02-Sep-03 03:33 by antonino

advertisement version: 2

Protocol Hello: OUI=0x00000C, Protocol ID=0x0112; payload len=27, value=0000000


VTP Management Domain: ''

Duplex: full


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