配置三层交换的综合事例

这个配置没有任何问题。

只要你能看明白，记住关键的命令，相信你已经对三层有更深的认识。



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网络基本情况


网络拓扑结构为:中心交换机采用Cisco Catalyst 4006-S3，

Supervisor Engine III G引擎位于第1插槽，用于实现三层交换;1块24口

1000Base-T模块位于第2插槽，用于连接网络服务器;1块6端口1000Base-X模块位

于第3插槽，用于连接6台骨干交换机。一台交换机采用Cisco Catalyst 3550-

24-EMI，并安装1块1000Base-X GBIC千兆模块。一台交换机采用Cisco

Catalyst 3550-24-SMI，也安装1块1000Base-X GBIC千兆模块。另外四台交换机

采用Cisco Catalyst 2950G-24-SMI，安装1块1000Base-T GBIC千兆模块。

所有服务器划分为一个VLAN，即VLAN 50。四台Catalyst 2950G-24-SMI交换机也只划分为一个VLAN，分别为VLAN 60、VLAN 70、VLAN 80和VLAN 90。

Catalyst 3550-24-EMI划分为4个VLAN，分别为VLAN 10、VLAN 20、VLAN 30和

VLAN 40。Catalyst 3550-24-SMI划分2个VLAN，分别为VLAN 60和VLAN 80，与另

外两台Catalyst 2950G-24-SMI交换机分别位于同一VLAN。



***************************实例分析****************************


由于所有Catalyst 2950G交换机都是一个独立的VLAN，因此，必须先在

这些交换机上创建VLAN(VLAN 60~VLAN 90)，并将所有端口都指定至该VLAN。然

后，再在Catalyst 4006交换机相应端口上分别创建VLAN。Catalyst 4006的

1000Base-X端口分别与各Catalyst 2950G的1000Base-X端口连接。其中，

GigabitEthernet3/2端口连接至1号Catalyst 2950交换机(VLAN 60)，GigabitEthernet3/3端口连接至2号Catalyst 2950交换机(VLAN 70)，GigabitEthernet3/4端口连接至3号Catalyst 2950交换机(VLAN 80)，GigabitEthernet3/5端口连接至4号Catalyst 2950交换机(VLAN 90)，GigabitEthernet3/6端口连接至6号楼交换机(VLAN 80)。


由于在Catalyst 3550-24-EMI上划分有4个VLAN(VLAN 10～VLAN 40)，而4个VLAN都需借助于一条1000Base-X链路实现与Catalyst 4006的GigabitEthernet3/1端口连接，因此，必须在Catalyst 4006与Catalyst 3550-24- EMI之间创建一个Trunk。


同样，在Catalyst 3550-24-SMI上划分有2个VLAN(VLAN 60和VLAN 80)，而4个VLAN都需借助于一条1000Base-X链路实现与Catalyst 4006的GigabitEthernet3/6端口连接，因此，必须在Catalyst 4006与Catalyst 3550-24- EMI之间创建一个Trunk。


另外，所有服务器均连接至Catalyst 4006的1000Base-T模块，并单独成为一个VLAN(VLAN 90)，因此，也必须为这些交换机创建一个VLAN，并将所有端口指定至该VLAN。需要注意的是，考虑到网络管理的需要，也可以剩余几个RJ-45端口(如21至24端口)不指定至任何VLAN，从而便于连接网络管理设备。默认状态下，所有端口都属于VLAN1，而且也只有在VLAN1中才能实现对网络中所有设备的管理。


***************************配置清单******************************


●Cisco Catalyst 4006交换机配置清单
Current configuration : 5594 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
service compress-config
!
hostname hsnc
!
boot system bootflash:cat4000-is-mz.121-8a.EW1.bin
no logging console
enable secret level 1 5 $1$rkQW$1HKyKdN5f.Ri5zxeoF8Yv/
!
ip subnet-zero
!
!
!
interface GigabitEthernet1/1
no snmp trap link-status
!--不为Supervisor Engine III G引擎中的1000Base-X插槽指定VLAN
interface GigabitEthernet1/2
no snmp trap link-status
!
!
interface GigabitEthernet2/1
switchport access vlan 50
no snmp trap link-status
!--将端口GigabitEthernet2/1指定至VLAN 50
!
interface GigabitEthernet2/2
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/3
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/4
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/5
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/6
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/7
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/8
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/9
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/10
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/11
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/12
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/13
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/14
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/15
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/16
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/17
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/18
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/19
switchport access vlan 50
no snmp trap link-status
!
interface GigabitEthernet2/20
switchport access vlan 50
no snmp trap link-status
!--不将GigabitEthernet2/20～24指定至任何VLAN
!
interface GigabitEthernet3/1
switchport trunk encapsulation dot1q
！--启用802.1Q Trunk封装协议，即在该端口创建Trunk
switchport trunk allowed vlan 1-80
！--允许vlan 1-90在该中继线通讯
！--可以拒绝或允许某个VLAN访问该Trunk
！--确保未被授权的VLAN通过该Trunk，实现VLAN的访问安全
switchport mode trunk
！--将该端口设置为Trunk
description netcenter
no snmp trap link-status
!
interface GigabitEthernet3/2
switchport access vlan 60
no snmp trap link-status
!--将端口GigabitEthernet3/2指定至VLAN 60
!
interface GigabitEthernet3/3
switchport access vlan 70
no snmp trap link-status
!--将端口GigabitEthernet3/3指定至VLAN 70
!
interface GigabitEthernet3/4
switchport access vlan 80
no snmp trap link-status
!--将端口GigabitEthernet3/4指定至VLAN 80
!
interface GigabitEthernet3/5
switchport access vlan 90
no snmp trap link-status
!--将端口GigabitEthernet3/5指定至VLAN 90
!
interface GigabitEthernet3/6
switchport trunk encapsulation dot1q
！--启用802.1Q Trunk封装协议，即在该端口创建Trunk
switchport trunk allowed vlan 1-80
！--允许vlan 1-90在该中继线通讯
！--可以拒绝或允许某个VLAN访问该Trunk
！--从而确保未被授权的VLAN通过该Trunk，实现VLAN访问安全
switchport mode trunk
！--将该端口设置为Trunk
description netcenter
no snmp trap link-status
!
interface Vlan1
description netmanger
no ip address
!
!--对VLAN1进行描述
interface Vlan10
description network center
no ip address
!--对VLAN2进行描述
!
interface Vlan20
description computer center
no ip address
!
interface Vlan30
description network lab
no ip address
!
interface Vlan40
description huaxuelou
no ip address
!
interface Vlan50
description wulilou
no ip address
!
interface Vlan60
description shengwulou
no ip address
!
interface Vlan70
description zhongwenxi
no ip address
!
interface Vlan80
description tushuguan
no ip address
!
!
line con 0
stopbits 1
line vty 0 4
password aaa
login
!
end

 

 

 

 

●Cisco Catalyst 3550-EMI配置清单 Building configuration... Current configuration : 4055 bytes ! version 12.1 no service pad service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname office ! enable secret 5 $1$p0fU$JeyPOM0RuL.Fqfe71efHF1 ! ip subnet-zero ! ! spanning-tree extend system-id ! ! ! interface FastEthernet0/1 switchport access vlan 10 !--将端口FastEthernet0/1指定至VLAN 10 no ip address ! interface FastEthernet0/2 switchport access vlan 10 no ip address ! interface FastEthernet0/3 switchport access vlan 10 no ip address ! interface FastEthernet0/4 switchport access vlan 10 no ip address ! interface FastEthernet0/5 switchport access vlan 10 no ip address ! interface FastEthernet0/6 switchport access vlan 20 no ip address !--将端口FastEthernet0/6指定至VLAN 20 ! interface FastEthernet0/7 switchport access vlan 20 no ip address ! interface FastEthernet0/8 switchport access vlan 20 no ip address ! interface FastEthernet0/9 switchport access vlan 20 no ip address ! interface FastEthernet0/10 switchport access vlan 20 no ip address ! interface FastEthernet0/11 switchport access vlan 30 no ip address !--将端口FastEthernet0/6指定至VLAN 30 ! interface FastEthernet0/12 switchport access vlan 30 no ip address ! interface FastEthernet0/13 switchport access vlan 30 no ip address ! interface FastEthernet0/14 switchport access vlan 30 no ip address ! interface FastEthernet0/15 switchport access vlan 30 no ip address ! interface FastEthernet0/16 switchport access vlan 30 no ip address ! interface FastEthernet0/17 switchport access vlan 30 no ip address ! interface FastEthernet0/18 switchport access vlan 30 no ip address ! interface FastEthernet0/19 switchport access vlan 40 no ip address !--将端口FastEthernet0/6指定至VLAN 40 ! interface FastEthernet0/20 switchport access vlan 40 no ip address ! interface FastEthernet0/21 switchport access vlan 40 no ip address ! interface FastEthernet0/22 switchport access vlan 30 no ip address ! interface FastEthernet0/23 switchport access vlan 40 no ip address ! interface FastEthernet0/24 switchport access vlan 40 no ip address ! interface GigabitEthernet0/1 switchport trunk encapsulation dot1q ！--启用802.1Q Trunk封装协议，即在该端口创建Trunk switchport trunk allowed vlan 1-80 ！--允许vlan 1-80在该中继线通讯 switchport mode trunk ！--将该端口设置为Trunk no ip address ! interface GigabitEthernet0/2 no ip address ! interface Vlan1 ip address 172.16.100.12 255.255.255.0 !--LAN1指定IP地址 no ip route-cache no ip mroute-cache ! ip classless ip http server ! ! ! ! line con 0 line vty 0 4 password aaa login line vty 5 15 login ! end     ●Cisco Catalyst 3550-SMI配置清单 Building configuration... Current configuration : 4055 bytes ! version 12.1 no service pad service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname office ! enable secret 5 $1$p0fU$JeyPOM0RuL.Fqfe71efHF1 ! ip subnet-zero ! ! spanning-tree extend system-id ! ! ! interface FastEthernet0/1 switchport access vlan 60 !--将端口FastEthernet0/1指定至VLAN 60 no ip address ! interface FastEthernet0/2 switchport access vlan 60 no ip address ! interface FastEthernet0/3 switchport access vlan 60 no ip address ! interface FastEthernet0/4 switchport access vlan 60 no ip address ! interface FastEthernet0/5 switchport access vlan 60 no ip address ! interface FastEthernet0/6 switchport access vlan 20 no ip address !--将端口FastEthernet0/6指定至VLAN 20 ! interface FastEthernet0/7 switchport access vlan 20 no ip address ! interface FastEthernet0/8 switchport access vlan 20 no ip address ! interface FastEthernet0/9 switchport access vlan 20 no ip address ! interface FastEthernet0/10 switchport access vlan 20 no ip address ! interface FastEthernet0/11 switchport access vlan 80 no ip address !--将端口FastEthernet0/6指定至VLAN 80 ! interface FastEthernet0/12 switchport access vlan 80 no ip address ! interface FastEthernet0/13 switchport access vlan 80 no ip address ! interface FastEthernet0/14 switchport access vlan 80 no ip address ! interface FastEthernet0/15 switchport access vlan 80 no ip address ! interface FastEthernet0/16 switchport access vlan 80 no ip address ! interface FastEthernet0/17 switchport access vlan 80 no ip address ! interface FastEthernet0/18 switchport access vlan 80 no ip address ! interface FastEthernet0/19 switchport access vlan 80 no ip address !--将端口FastEthernet0/6指定至VLAN 80 ! interface FastEthernet0/20 switchport access vlan 80 no ip address ! interface FastEthernet0/21 switchport access vlan 80 no ip address ! interface FastEthernet0/22 switchport access vlan 80 no ip address ! interface FastEthernet0/23 switchport access vlan 80 no ip address ! interface FastEthernet0/24 switchport access vlan 80 no ip address ! interface GigabitEthernet0/1 switchport trunk encapsulation dot1q ！--启用802.1Q Trunk封装协议，即在该端口创建Trunk switchport trunk allowed vlan 1-80 ！--允许vlan 1-80在该中继线通讯 switchport mode trunk ！--从将该端口设置为Trunk no ip address ! interface GigabitEthernet0/2 no ip address ! interface Vlan1 ip address 172.16.100.13 255.255.255.0 !--为LAN1指定IP地址 no ip route-cache no ip mroute-cache ! ip classless ip http server ! ! ! ! line con 0 line vty 0 4 password aaa login line vty 5 15 login ! end

 

 

 

 

●Cisco Catalyst 2950G配置清单
四台Cisco Catalyst 2950G的配置基本相同，下面仅列出VLAN 60的配置情况。
Building configuration...

Current configuration : 2143 bytes
!
version 12.1
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname msl
!
enable password aaa
!
ip subnet-zero
!
!
spanning-tree extend system-id
!
!
interface FastEthernet0/1
switchport access vlan 60
no ip address
!
interface FastEthernet0/2
switchport access vlan 60
no ip address
!
interface FastEthernet0/3
switchport access vlan 60
no ip address
!
interface FastEthernet0/4
switchport access vlan 60
no ip address
!
interface FastEthernet0/5
switchport access vlan 60
no ip address
!
interface FastEthernet0/6
switchport access vlan 60
no ip address
!
interface FastEthernet0/7
switchport access vlan 60
no ip address
!
interface FastEthernet0/8
switchport access vlan 60
no ip address
!
interface FastEthernet0/9
switchport access vlan 60
no ip address
!
interface FastEthernet0/10
switchport access vlan 60
no ip address
!
interface FastEthernet0/11
switchport access vlan 60
no ip address
!
interface FastEthernet0/12
switchport access vlan 60
no ip address
!
interface FastEthernet0/13
switchport access vlan 60
no ip address
!
interface FastEthernet0/14
switchport access vlan 60
no ip address
!
interface FastEthernet0/15
switchport access vlan 60
no ip address
!
interface FastEthernet0/16
switchport access vlan 60
no ip address
!
interface FastEthernet0/17
switchport access vlan 60
no ip address
!
interface FastEthernet0/18
switchport access vlan 60
no ip address
!
interface FastEthernet0/19
switchport access vlan 60
no ip address
!
interface FastEthernet0/20
switchport access vlan 60
no ip address
!
interface FastEthernet0/21
switchport access vlan 60
no ip address
!
interface FastEthernet0/22
switchport access vlan 60
no ip address
!
interface FastEthernet0/23
switchport access vlan 60
no ip address
!
interface FastEthernet0/24
switchport access vlan 60
no ip address
!
interface GigabitEthernet0/1
no ip address
!
interface GigabitEthernet0/2
no ip address
!
interface Vlan1
ip address 172.16.100.10 255.255.255.0
!
ip classless
ip http server
!
!
!
!
line con 0
line vty 0 4
password aaa
login
line vty 5 15
login
!
end