ccna-乾颐堂课前-课程讲义交换trouble

常见故障排除工具（一）commandSwitch#10.1.1.100Type

esc sequence

to

abort.Sending

5,

100-byte

ICMP

Echos

to

10.1.1.100,

timeout

is

2

seconds:!!!!!Success

rate

is

100

percent

(5/5),

round-trip

min/avg/max

=

1/203/1007

msC:\>ing[192.0.43.10]

with

32

bytes

of

data:Replyfrom192.0.43.10:bytes=32time=107msTTL=243Replyfrom192.0.43.10:bytes=32time=107msTTL=243Replyfrom192.0.43.10:bytes=32time=137msTTL=243Replyfrom192.0.43.10:bytes=32time=107msTTL=243statistics

for

192.0.43.10:Packets:

Sent

=

4,

Received

=

4,

Lost

=

0

(0%

loss),Approximate

round

trip

times

in

milli-seconds:Minimum

=

107ms, um

=

137ms,

Average

=

114msInterconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0常见故障排除工具（二）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0netSwitch1#

net

10.1.20.1Trying

10.1.20.1

...

OpenSwitch2>介质问题—铜缆铜缆可能会出现以下问题:线路会受损电磁干扰流量模式变化安装新设备Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0介质问题—光纤光缆可能会出现以下问题:折弯损耗:弯曲半径过小导致光的纤维损坏–光纤芯或包覆层弯曲小于临界角漏光熔纤损耗Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0排除交换机媒介故障（一）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0排除交换机媒介故障（二）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0检查接口状态：Switch#show

interface

FastEthernet0/1FastEthernet0/1

is

up,

line

protocol

is

upHardware

is

Fast

Ethernet,

address

is

0022.91c4.0e01

(bia

0022.91c4.0e01)MTU

1500

bytes,

BW

100000

Kbit,

DLY

100

usec,<output

omitted>接口状态检验（一）过多的噪波:许多CRC错误存在–检查电缆损坏和正确的长度并且寻找噪波来源过多的

:一般是双工不匹配造成的配置全双工Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0接口状态检验（二）Switch#show

interface

FastEthernet0/1FastEthernet0/1

is

up,

line

protocol

is

upHardware

is

Fast

Ethernet,

address

is

0022.91c4.0e01

(bia0022.91c4.0e01)MTU

1500

bytes,

BW

100000

Kbit,

DLY

100

usec,<output

omitted>2295197

packets

input,

305539992

bytes,

0

no

bufferReceived

1925500

broadcasts,

0

runts,

0

giants,

0

throttles3

input

errors,

3

CRC,

0

frame,

0

overrun,

0

ignored0

watchdog,

68

multicast,

0

pause

input0

input

packets

with

dribble

condition

detected3594664

packets

output,

436549843

bytes,

0

underruns1935

output

errors,1790

collisions,10

interface

resets0

unknown

protocol

drops0

babbles,

135

late

collision,

0

deferred<output

omitted>Displays

interface

status

and

statisticsInterconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0端口问题（一）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0端口问题大多跟双工和速率有关Duplex-related

issues

result

from

a

mismatch

in

duplex

settings:Speed-related

issues

result

from

a

mismatch

in

speed

settings:端口问题（二）双工相关问题实例:一端双工，一端半双工导致双工不匹配一端全双工，一端自动协商:–如果协商失败则工作在半双工，导致双工不匹配一端全双工，一端自动协商:如果协商失败，将工作在半双工两端都工作在半双工，没有双工不匹配的情况Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0端口问题（三）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0的双工问题实例:两端全设置为自动协商:一端全双工失败，另外一端半双工失败Example:A

Gigabit

Ethernet

interface

defaults

tofull

duplex,

while

a10/100defaultsto

halfduplex.两端全设置为自动协商:两端如果协商失败，则都工作在半双工模式两端协商为半双工，没有双工不匹配的问题端口问题（四）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0速率相关问题实例:一端设置为10M，另外一端设置100M，造成速率不匹配一端设置为高速，另外一端设置为自动协商:如果协商失败，则恢复使用最佳速率两端都设置为自动协商:如果协商失败，两端都恢复使用最低速率两端都使用最低速率，则没有速率不匹配的问题端口问题故障（一）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0%CDP-4-DUPLEX_MISMATCH:

duplex

mismatch

discovered

on

FastEthernet0/1

(nothalf

duplex)Show

interface

f0/1Troubleshooting

duplex-related

issues:端口问题故障 （二）Interconnecting

CiscoNetworking

Devices,

Part

1(ICND1)

v2.0Switch#show

interfaces

FastEthernet

0/1FastEthernet0/1

is

up,

line

protocol

is

up

(connected)Hardware

is

Fast

Ethernet,

address

is

001e.147c.6f01

(bia001e.147c.6f01)MTU

1500

bytes,

BW

100000

Kbit/sec,

DLY

100

usec,reliability

255/255,

txload

1/255,

rxload

1/255Encapsulation

ARPA,

loopback

not

setKeepalive

set

(10

sec)Full-duplex,

100Mb/s,

media

type

is

10/100BaseTXinput

flow-control

is

off,

outputflow-control

is

unsupportedARP

type:

ARPA,

ARP

Timeout

04:00:00Last

input

00:00:28,

output

00:00:01,

output

hang

neverLast

clearing

of

"show

interface"

counters

neverInput

queue:

0/75/0/0

(size/max/drops/flushes);

Total

output

drops:

0Queueing

strategy:

fifoOutput

queue:

0/40

(size/max)Displays

duplex

and

speed

statisticsVLAN排错（一）Interconnecting

CiscoNetworking

Devices,

Part

2(ICND2)

v2.0VLAN排错（二）SW1#show

mac

address-table

interface

FastEthernet

0/1Mac

Address

TableTypePortsFa0/1Fa0/1Vlan Mac

Address10

000c.296a.a21c10

000f.34f9.9181Total

Mac

Addresses

forDYNAMICDYNAMICthis

criterion:

2Interconnecting

CiscoNetworking

Devices,

Part

2(ICND2)

v2.0查看MAC地址表VLAN排错（三）SW1#show

interfaces

FastEthernet

0/1

switchportName:

Fa0/1Switchport:

EnabledAdministrative

Mode:

static

accessOperational

Mode:

static

accessAdministrative

Trunking

Encapsulation:

dot1qOperational

Trunking

Encapsulation:

nativeNegotiation

of

Tr