使用外部路由器配置VLAN间路由

!-- Set the privileged mode
!-- and Telnet password on the switch.

switch#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
switch(config)#hostname 3512xl
3512xl(config)#enable password mysecret
3512xl(config)#line vty 0 4
3512xl(config-line)#login
3512xl(config-line)#password mysecret
3512xl(config-line)#exit
3512xl(config)#no logging console
3512xl(config)#^Z


!-- Set the IP address and default gateway for VLAN1 for management purposes.

3512xl#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
3512xl(config)#interface vlan 1
3512xl(config-if)#ip address 10.10.10.2 255.255.255.0
3512xl(config-if)#exit
3512xl(config)#ip default-gateway 10.10.10.1
3512xl(config)#end

!-- Set the VTP Mode. In our example, we have set the mode to be transparent. 
!-- Depending on your network, set the VTP Mode accordingly. 

3512xl#vlan database
3512xl(vlan)#vtp transparent
Setting device to VTP TRANSPARENT mode.


!-- Adding VLAN2. VLAN1 already exists by default.

3512xl(vlan)#vlan 2
VLAN 2 added:
Name: VLAN0002
3512xl(vlan)#exit
APPLY completed.
Exiting....


!-- Enable trunking on the interface fastEthernet 0/1.
!-- Enter the trunking encapsulation as either as dot1q.

3512xl#configure terminal 
Enter configuration commands, one per line. End with CNTL/Z. 
3512xl(config)#interface fastEthernet 0/1 
3512xl(config-if)#switchport mode trunk 
3512xl(config-if)#switchport trunk encapsulation dot1q  

!-- In case of 2940/2950 series switches, none of the above two commands are used, 
!-- 2940/2950 series switches only support 802.1q encapsulation which is configured automatically, 
!-- when trunking is enabled on the interface by using switchport mode trunk command. 
!-- In case of dot1q, you need to make sure that the native VLAN matches across the link. 

!-- On Catalyst Switches, by default, the native VLAN is 1. 
!-- It is very important that you change the native VLAN on the router accordingly. 
!-- You may change the native VLAN, if needed, by using the following command: 
!-- 3512xl(config-if)#switchport trunk native vlan 
         
          

!-- Allow all VLANs on the trunk.
 
3512xl(config-if)#switchport trunk allowed vlan all 
3512xl(config-if)#exit 

!-- The following set of commands can place FastEthernet 0/2 into VLAN2.  

3512xl(config)#interface fastEthernet 0/2 
3512xl(config-if)#switchport mode access 
3512xl(config-if)#switchport access vlan 2 
3512xl(config-if)#exit 

!-- FastEthernet 0/3 is already in VLAN1 by default.  

3512xl(config)#interface fastEthernet 0/3 
3512xl(config-if)#switchport mode access 
3512xl(config-if)#^Z 

!-- Remember to save the configuration.  

3512xl#write memory 
Building configuration... 

3512xl# 

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

3512xl#show running-config
Building configuration...

Current configuration:

!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname 3512xl
!
no logging console
enable password mysecret
!
!
!
!
!
ip subnet-zero
!
!
!
interface FastEthernet0/1
  switchport mode trunk
  switchport trunk encapsulation dot1q 
!
interface FastEthernet0/2
 switchport access vlan 2
 switchport mode access
!
interface FastEthernet0/3
 switchport mode access
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface GigabitEthernet0/1
!
interface GigabitEthernet0/2
!
interface VLAN1
 ip address 10.10.10.2 255.255.255.0
 no ip directed-broadcast
 no ip route-cache
!
ip default-gateway 10.10.10.1
!
line con 0
 transport input none
 stopbits 1
line vty 0 4
 password mysecret
 login
line vty 5 15
 login
!
end 

注：下一个屏幕截图显示了在Cisco 2600路由器上输入的命令。命令之间的注释以斜体形式添加，以解释某些命令和步骤。

!-- Set the privileged mode 
!-- and Telnet password on the router.

Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#hostname c2600

c2600(config)#enable password mysecret
c2600(config)#line vty 0 4
c2600(config-line)#login
c2600(config-line)#password mysecret
c2600(config-line)#exit
c2600(config)#no logging console
c2600(config)#^Z

c2600#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.


!-- Select FastEthernet 0/0 for the trunk configuration. 
!-- No L2 or Layer 3 (L3) configuration is done here.

c2600(config)#interface fastEthernet 0/0
c2600(config-if)#no shut
c2600(config-if)#exit

!-- Enable trunking on the sub-interface FastEthernet 0/0.1. 
!-- The actual trunks are configured on the sub-interfaces.

c2600(config)#interface fastEthernet 0/0.1

!-- Enter the trunking encapsulation as dot1q. 
!-- Make sure that the native VLAN matches across the link. 
!-- On the switch, by default, the native VLAN is 1. 
!-- On the router, configure VLAN1 as the native VLAN.

c2600(config-subif)#encapsulation dot1Q 1 ?
  native  Make this is native vlan
  <cr>
c2600(config-subif)#encapsulation dot1Q 1 native

!-- On the switch, if you have a native VLAN other than VLAN1, 
!-- on the router, configure the same VLAN to be the native VLAN, 
!-- by using the above command.

注:Cisco IOS版本12.1(3)T中添加了encapsulation dot1Q 1 native命令。

!-- Configure L3 information on the sub-interface 0/0.1.

c2600(config-subif)#ip address 10.10.10.1 255.255.255.0
c2600(config-subif)#exit


!-- Enable trunking on the sub-interface FastEthernet 0/0.2. 
!-- The actual trunks are configured on the sub-interfaces.
!-- Enter the trunking encapsulation as dot1q: 

c2600(config)#int fastEthernet 0/0.2 
c2600(config-subif)#encapsulation dot1Q 2 

!-- Configure L3 information on the sub-interface 0/0.2.  

c2600(config-subif)#ip address 10.10.11.1 255.255.255.0 
c2600(config-subif)#exit 
c2600(config)#^Z 

!-- Remember to save the configuration.  

c2600#write memory 
Building configuration... 
[OK] 
c2600#

注：要使此设置正常运行，并且要在workstation1和workstation2之间成功ping，您需要确保工作站上的默认网关设置正确。对于workstation1，默认网关必须为10.10.11.1；对于workstation2，默认网关必须为10.10.10.1。

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

c2600#show running-config
Building configuration...

Current configuration:
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname c2600
!
no logging console
enable password mysecret
!
!
!
!
!
ip subnet-zero
!
!
!
!
!
!
!
!
!
!
interface FastEthernet0/0
no ip address
duplex auto
speed auto
!
interface FastEthernet0/0.1
encapsulation dot1q 1 native
ip address 10.10.10.1 255.255.255.0
no ip redirects
!
interface FastEthernet0/0.2
encapsulation dot1q 2
ip address 10.10.11.1 255.255.255.0
no ip redirects
!
!
interface FastEthernet0/1
no ip address
shutdown
duplex auto
speed auto
!
ip classless
no ip http server
!
!
!
line con 0
transport input none
line aux 0
line vty 0 4
password mysecret
login
!
no scheduler allocate
end