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"late collision error" on Cisco Router 800 series

nguyenxuanhoa
Level 1
Level 1

Hi everybody,

My Router have one interface vlan1 connect to internal network, the other interface fe4 connect to ISP (Wan connection - fiber optics)

I have "late collision error" on fe4 when use show interface fe4 command, but no collision when I detect on vlan1.

The question is: can the problem be in our internal network or only because of WAN connection??? And anyone know the solution for it, i'm just thinking of duplex mismatch in WAN but can do nothing because cannot access ISP's side.

Thanks for your help,

15 Replies 15

John Blakley
VIP Alumni
VIP Alumni

Yes, hard code the duplex and speed. If you do a "show int fe4" do you see a duplexing or speed mismatch?

John

HTH, John *** Please rate all useful posts ***

hey Blakley,

Do you think it's possible that the problem is internal network? or only Wan?

The router will tell you what interface is having the problem. I would start there....

John

HTH, John *** Please rate all useful posts ***

yeap,

I start with WAN interface. Duplex mode is auto. Speed is also auto.

I try to change Duplex mote to half-duplex, still got this error. Then try with full-duplex, the connection is down. So, I'm thinking whether or not it's because of Internal Network. But when I check interface vlan1 to our internal network, it got no collision error.

You probably won't see a collision on your vlan because that's just a virtual link. This is a physical problem. If you do auto/auto, can you post "sh int fe4"?

HTH, John *** Please rate all useful posts ***

FastEthernet4 is up, line protocol is up

  Hardware is PQII_PRO_UEC, address is 8843.e187.bf48 (bia 8843.e187.bf48)

  Description: $ETH-LAN$

  Internet address is X.X.X.38/30

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

     reliability 254/255, txload 1/255, rxload 1/255

  Encapsulation ARPA, loopback not set

  Keepalive set (10 sec)

  Half-duplex, 100Mb/s, 100BaseTX/FX

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

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

  Last clearing of "show interface" counters never

  Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 2

  Queueing strategy: fifo

  Output queue: 0/40 (size/max)

  5 minute input rate 183000 bits/sec, 59 packets/sec

  5 minute output rate 157000 bits/sec, 65 packets/sec

     9208320 packets input, 609241620 bytes

     Received 40 broadcasts, 0 runts, 0 giants, 0 throttles

     4 input errors, 0 CRC, 0 frame, 0 overrun, 4 ignored

     0 watchdog

     0 input packets with dribble condition detected

     7672607 packets output, 1479444583 bytes, 0 underruns

     245691 output errors, 253375 collisions, 47 interface resets

     0 unknown protocol drops

     0 babbles, 18539 late collision, 227103 deferred

     0 lost carrier, 0 no carrier

     0 output buffer failures, 0 output buffers swapper out

Here is for vlan1 interface (internal network):

Vlan1 is up, line protocol is up
  Hardware is EtherSVI, address is 8843.e187.bf44 (bia 8843.e187.bf44)
  Description: $ETH-SW-LAUNCH$$INTF-INFO-HWIC 4ESW$
  Internet address is 192.168.1.254/24
  MTU 1500 bytes, BW 100000 Kbit/sec, DLY 100 usec,
     reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA, loopback not set
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:00, output never, output hang never
  Last clearing of "show interface" counters never
  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 212000 bits/sec, 73 packets/sec
  5 minute output rate 175000 bits/sec, 60 packets/sec
     7908552 packets input, 1533840901 bytes, 0 no buffer
     Received 218624 broadcasts, 0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     9181701 packets output, 601468740 bytes, 0 underruns
     0 output errors, 1 interface resets
     19107 unknown protocol drops
     0 output buffer failures, 0 output buffers swapped out

This is from your FE4:

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

Is that still hard coded at half, or is that auto?

HTH, John *** Please rate all useful posts ***

No, fe4 I configure as auto:

interface FastEthernet4
description $ETH-LAN$
ip address X.X.X.38 255.255.255.252
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
!

try setting it again with:

speed 100

duplex full

HTH, John *** Please rate all useful posts ***

ok, I will try to do it later 1more times. (now cannot because Im remoting to the router from outside, if I apply and the connection is down, I cannot access again

As I said, yesterday I changed it to Full duplex but the connection was down immediately.

If that doesn't work, then the next step would be to get with the provider and see if they can hardcode their end as well.

HTH, John *** Please rate all useful posts ***

Yeap, thank you so much for your help.

hi John,

It works now.

Maybe last time I didnt put speed 100 so WAN connection is down.

Now it's ok.

Thanks for your help.

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