不同vlan间的通信简单配置
1．单臂路由(图)
环境：一台路由器，一台二层交换机，两台pc机
二层交换机的配置
一般模式：
Switch>
输入enable进入特权模式：
Switch>enable
输入configure terminal进入全局配置模式：
Switch#configure terminal
Enter configuration commands, one per line. End with CNTL/Z. 创建vlan 10 和vlan 20：
Switch(config)#vlan 10
Switch(config-vlan)#vlan 20
Switch(config-vlan)# exit
进入接口配置模式：
Switch(config)#interface fastEthernet 0/1
把0/1变成trunk口（默认是access口）
Switch(config-if)#switchport mode trunk
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up
Switch(config-if)#exit
进入接口配置模式分别把对应的接口，加入对应的vlan：
Switch(config)#interface fastEthernet 1/1
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 10
Switch(config-if)#interface fastEthernet 2/1
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 20
到此二层交换机配置完毕！
路由器的配置：
Router>
Router>enable
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#inter fas 0/0
Router(config-if)#no ip address
Router(config-if)#no shutdown
注意：单臂路由的配置父接口一定要no shutdown
%LINK-5-CHANGED: Interface FastEthernet0/0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0, changed state to up
Router(config-if)#exit
Router(config)#int fas 0/0.10
%LINK-5-CHANGED: Interface FastEthernet0/0.10, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0.10, changed state to up
Router(config-subif)#encapsulation dot1Q 10
注意：在配置ip时一定要先封装802.1q协议
Router(config-subif)#ip address 192.168.10.1 255.255.255.0
Router(config-subif)#no shutdown
Router(config-subif)#int fas 0/0.20
%LINK-5-CHANGED: Interface FastEthernet0/0.20, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/0.20, changed state to up
Router(config-subif)#ip address 192.168.20.1 255.255.255.0
% Configuring IP routing on a LAN subinterface is only allowed if that subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q,
or ISL vLAN.
Router(config-subif)#encapsulation dot1Q 20
Router(config-subif)#ip address 192.168.20.1 255.255.255.0
Router(config-subif)#no shutdown
Router(config-subif)#
查看路由表：
Router#show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2 E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
* - candidate default, U - per-user static route, o - ODR
P - periodic downloaded static route
Gateway of last resort is not set
C 192.168.10.0/24 is directly connected, FastEthernet0/0.10
C 192.168.20.0/24 is directly connected, FastEthernet0/0.20 Router#
PC0的配置：
ip 192.168.10.10
netmask 255.255.255.0
gateway 192.168.10.1
PC1的配置：
ip 192.168.20.20
