late collisions problem

Vishnu Reddy · ‎01-13-2015

Hi,

I have an ASA 7.2(1) connected to Gateway router and Gateway router to Verizon Internet. The bandwidth for internet is 10Mbps.

Gateway Router Config

-------------------------

interface FastEthernet0/1
ip address xxx.xxx.22.254 255.255.255.192
ip flow ingress
ip flow egress
speed 100
full-duplex
end

show int fa0/1
FastEthernet0/1 is up, line protocol is up
Hardware is AmdFE, address is 000d.bdc7.3fe1 (bia 000d.bdc7.3fe1)
Internet address is xxx.xxx.22.254/26
MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec,
     reliability 253/255, txload 5/255, rxload 6/255
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 00:00:00, output 00:00:00, output hang never
Last clearing of "show interface" counters 25w0d
Input queue: 0/75/63/0 (size/max/drops/flushes); Total output drops: 0
Queueing strategy: fifo
Output queue: 0/40 (size/max)
5 minute input rate 2704000 bits/sec, 536 packets/sec
5 minute output rate 2339000 bits/sec, 545 packets/sec
     1121556795 packets input, 935742857 bytes
     Received 499709 broadcasts, 0 runts, 0 giants, 0 throttles
     150070210 input errors, 150068465 CRC, 0 frame, 597 overrun, 1148 ignored
     0 watchdog
     0 input packets with dribble condition detected
     1647880040 packets output, 1398321396 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 output buffer failures, 0 output buffers swapped out
-------------------------------------------------------------------------------------------------------------------------------------------------------------------

ASA

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This is ASA connecting to Fa0/1 of Gateway Router. It is configured as auto for speed and duplex as can be seen below.

show int e0/0
Interface Ethernet0/0 "Outside", is up, line protocol is up
Hardware is i82546GB rev03, BW 100 Mbps
        Auto-Duplex(Half-duplex), Auto-Speed(100 Mbps)
        MAC address 0018.b9a8.aa08, MTU 1500
        IP address xxx.xxx.22.230, subnet mask 255.255.255.128
        224179996 packets input, 67409913590 bytes, 0 no buffer
        Received 2154028 broadcasts, 0 runts, 0 giants
        0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
        0 L2 decode drops
        246841893 packets output, 56778167701 bytes, 0 underruns
        0 output errors, 2254524 collisions, 0 interface resets
        0 babbles, 1319826 late collisions, 9451170 deferred
        0 lost carrier, 0 no carrier
        input queue (curr/max blocks): hardware (0/0) software (0/0)
        output queue (curr/max blocks): hardware (0/26) software (0/0)
Traffic Statistics for "Outside":
        224179422 packets input, 63091703732 bytes
        248161719 packets output, 53332938745 bytes
        1985915 packets dropped
      1 minute input rate 7 pkts/sec, 791 bytes/sec
      1 minute output rate 11 pkts/sec, 1286 bytes/sec
      1 minute drop rate, 0 pkts/sec
      5 minute input rate 14 pkts/sec, 4022 bytes/sec
      5 minute output rate 19 pkts/sec, 1753 bytes/sec
      5 minute drop rate, 0 pkts/sec

interface Ethernet0/0
nameif Outside
security-level 0
ip address xxx.xxx.22.230 255.255.255.128

The copper coming from gateway router is connected to 3570 switch and from 3750 switch the cable goes to ASA. This is a DMZ switch in the middle of gateway router and the ASA.

On the gateway router its configured as speed 100 and duplex full and at the ASA site its left to Auto.

Should I configure the Gateway router for Auto(speed/duplex) or do a manual configuration and do same at ASA also?

How could i overcome this problem? Thanks in advance.

Henrik Grankvist · ‎01-13-2015

Hi

You have a duplex mismatch because you configured the duplex to be "full" manually on the router while leaving it to auto on the ASA.

Either you can configure the ASA to have full duplex manually or remove the "duplex full" on the router, which would make the router and ASA negotiate the duplex to full.

Vishnu Reddy · ‎01-13-2015

Thanks for your response.

I mean there is a 3750 switch in between those devices. Configuring speed to Auto on the Gateway router will work just fine. I want to be sure that you know the setup.

Thanks in advance.

Leo Laohoo · ‎01-13-2015

reliability 253/255, txload 5/255, rxload 6/255

Line error is caused by a faulty cable. Can you specify what is the exact model of the switch. If this is a 2960 then there's a chance you can run a TDR to determine where is the faulty cable. Plain 3560 do not support TDR.

Vishnu Reddy · ‎01-14-2015

Thanks for your reply.

I have never worked on TDR. I believe the switch is 3750 switch. Instead can I replace the cable itself.

Thanks in advance.

Leo Laohoo · ‎01-14-2015

I believe the switch is 3750 switch.

It won't be because the interface port is "FastEthernet0/1".

milan.kulik · ‎01-14-2015

Hi, IMHO, you should also fix the duplex problem by configuring the ports the same way on the switch and the devices connected to it. Best regards, Milan

Vishnu Reddy · ‎01-15-2015

Thanks for your reply.

I will try that and post it if that works.

Leo Laohoo · ‎01-15-2015

I have never worked on TDR. I believe the switch is 3750 switch.

Have a read of this: How to use Time-Domain Reflectometer (TDR)

milan.kulik · ‎01-13-2015

Hi, as you say "The copper coming from gateway router is connected to 3570 switch and from 3750 switch the cable goes to ASA.", you need to configure duplex and speed the same way for the router/switch and switch/ASA port pairs. Some people prefer autonegotiation as it's the default value on most Cisco devices. But I'd personally prefer to set all ports to 100Mbps/Full duplex if possible. I guess your switch has got 100Mbps/Full duplex configured on both ports (as it's OK with the router port which is also configured for 100/Full but the autonegotiation fails on your ASA. (Can you check what's really configured on the switch ports?) So it's possible all you need is to set the ASA port to 100/Full. Best regards, Milan