單臂路由實驗
單臂路由是在沒有三層交換機的情況下實現VLAN間通信的最基本方法
如圖：R1和S1之間使用子接口，通過配置單臂路由完成VLAN間路由
S!:
Router>en
Router#conf t
Router(config)#host switch
switch(config)#no ip domai lookup
switch(config)#int f0/1
switch(config-if)#switchport trunk encapsulation dot1q
switch(config-if)#switchport mode trunk
switch(config-if)#no shutdown
switch(config-if)#end
switch#vlan database
switch(vlan)#vlan 10 name VLAN_A
VLAN 10 added:
Name: VLAN_A
switch(vlan)#vlan 20 name VLAN_B
VLAN 20 added:
Name: VLAN_B
switch(vlan)#exit
APPLY completed.
Exiting....
switch#conf t
switch(config)#int f0/2
switch(config-if)#switchport mode access
switch(config-if)#switchport access vlan 10
switch(config-if)#int f0/3
switch(config-if)#switchport mode access
switch(config-if)#switchport access vlan 20
switch(config-if)#^Z
switch#
-----------------------
R1:
Router>en
Router#conf t
Router(config)#host R1
R1(config)#no ip domain lookup
R1(config)#int f0/0
R1(config-if)#no shut
R1(config-if)#int f0/0.1 //配置子接口
R1(config-subif)#ip add 192.1.1.1 255.255.255.0
% 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.
R1(config-subif)#encapsulation dot1Q 10 //封裝VLAN類型爲802.1Q,標籤爲10
R1(config-subif)#ip add 192.1.1.1 255.255.255.0 //配置IP地址,實際上就是VLAN 10 計算機的網關
R1(config-subif)#no shut
R1(config-subif)#int f0/0.2
R1(config-subif)#encapsulation dot1Q 20
R1(config-subif)#ip add 193.1.1.1 255.255.255.0
R1(config-subif)#no shut
R1(config-subif)#end
R2:
Router>en
Router#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#host R2
R2(config)#int f0/0
R2(config-if)#ip add 192.1.1.2 255.255.255.0
R2(config-if)#no shut
R2(config-if)#ip route 0.0.0.0 0.0.0.0 192.1.1.1
R3：
Router>en
Router#conf t
Router(config)#host R3
R3(config)#int f0/0
R3(config-if)#ip add 193.1.1.2 255.255.255.0
R3(config-if)#no shut
R3(config-if)#ip route 0.0.0.0 0.0.0.0 193.1.1.1
*********
測試：
R2#ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/34/64 ms
R2#ping 193.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/60/128 ms
R2#ping 192.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/36/100 ms
R2#
*************
R3#ping 193.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 193.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 80/168/312 ms
R3#ping 192.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 84/188/424 ms
R3#ping 192.1.1.2
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.1.1.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 400/478/652 ms
R3#
R1#sh ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, 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 193.1.1.0/24 is directly connected, FastEthernet0/0.2
C 192.1.1.0/24 is directly connected, FastEthernet0/0.1
R2#sh ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, 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 192.1.1.1 to network 0.0.0.0
C 192.1.1.0/24 is directly connected, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 192.1.1.1
R3#sh ip route
Codes: C - connected, S - static, 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
i - IS-IS, su - IS-IS summary, 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 193.1.1.1 to network 0.0.0.0
C 193.1.1.0/24 is directly connected, FastEthernet0/0
S* 0.0.0.0/0 [1/0] via 193.1.1.1