所有私网可以通过ospf协议互相通信

第一步：配置路由器的环回和接口

[r1]int lo0
[r1-LoopBack0]ip add 192.168.1.1 24
[r1]int g0/0/1
[r1-GigabitEthernet0/0/1]ip add 16.1.1.1 24 
[r1-GigabitEthernet0/0/1]int g0/0/0
[r1-GigabitEthernet0/0/0]ip add 61.1.1.1 24
[r1-GigabitEthernet0/0/0]

[r2]int lo0
[r2-LoopBack0]ip add 192.168.2.1 24
[r2]int g0/0/0
[r2-GigabitEthernet0/0/0]ip add 26.1.1.1 24 
[r2-GigabitEthernet0/0/0]

[r3]int lo0
[r3-LoopBack0]ip add 192.168.3.1 24
[r3-LoopBack0]q
[r3]int g0/0/0
[r3-GigabitEthernet0/0/0]ip add 36.1.1.1 24

[r4]int  lo0
[r4-LoopBack0]ip add 192.168.4.1 24
[r4]int g0/0/0
[r4-GigabitEthernet0/0/0]ip add 46.1.1.1 24

[r5]int lo0
[r5-LoopBack0]ip add 192.168.5.1 24
[r5]int g0/0/0
[r5-GigabitEthernet0/0/0]ip add 56.1.1.1 24

[r6]int lo0
[r6-LoopBack0]ip add 6.6.6.6 24
[r6]int g0/0/1
[r6-GigabitEthernet0/0/1]ip add 16.1.1.2 24
[r6-GigabitEthernet0/0/1]int g0/0/0
[r6-GigabitEthernet0/0/0]ip add 61.1.1.2 24
[r6-GigabitEthernet0/0/0]int g0/0/2
[r6-GigabitEthernet0/0/2]ip add 26.1.1.2 24 
[r6-GigabitEthernet0/0/2]int g4/0/0
[r6-GigabitEthernet4/0/0]ip add 36.1.1.2 24
[r6-GigabitEthernet4/0/0]int g4/0/1
[r6-GigabitEthernet4/0/1]ip add 46.1.1.2 24
[r6-GigabitEthernet4/0/1]int g4/0/2
[r6-GigabitEthernet4/0/2]ip add 56.1.1.2 24

第二步：配置路由缺省，使得内网互通

[r1]ip route-static 0.0.0.0 0 16.1.1.2
[r1]ip route-static 0.0.0.0 0 61.1.1.2

[r2]ip route-static 0.0.0.0 0 26.1.1.2

[r3]ip route-static 0.0.0.0 0 36.1.1.2

[r4]ip route-static 0.0.0.0 0 46.1.1.2

[r5]ip route-static 0.0.0.0 0 56.1.1.2

第三步：建立r1/2/3MGRE结构

[r1]interface Tunnel 0/0/0
[r1-Tunnel0/0/0]ip add 10.1.1.1 24
[r1-Tunnel0/0/0]tunnel-protocol gre p2mp 
[r1-Tunnel0/0/0]source 61.1.1.1
[r1-Tunnel0/0/0]nhrp entry multicast dynamic 
[r1-Tunnel0/0/0]nhrp network-id 100

[r2]interface Tunnel 0/0/0
[r2-Tunnel0/0/0]ip add 10.1.1.2 24
[r2-Tunnel0/0/0]tunnel-protocol gre p2mp 
[r2-Tunnel0/0/0]source GigabitEthernet 0/0/0
[r2-Tunnel0/0/0]nhrp entry 10.1.1.1 61.1.1.1 register 
[r2-Tunnel0/0/0]nhrp network-id 100

[r3]interface Tunnel 0/0/0
[r3-Tunnel0/0/0]ip add 10.1.1.3 24
[r3-Tunnel0/0/0]tunnel-protocol gre p2mp 
[r3-Tunnel0/0/0]source GigabitEthernet 0/0/0
[r3-Tunnel0/0/0]nhrp entry 10.1.1.1 61.1.1.1 register 
[r3-Tunnel0/0/0]nhrp network-id 100

第四步：建立r1/4/5的MGRE结构

[r1]interface Tunnel 0/0/1
[r1-Tunnel0/0/1]ip add 10.1.2.1 24
[r1-Tunnel0/0/1]tunnel-protocol gre p2mp 
[r1-Tunnel0/0/1]source 16.1.1.1
[r1-Tunnel0/0/1]nhrp entry multicast dynamic 
[r1-Tunnel0/0/1]nhrp network-id 100

[r4]interface Tunnel 0/0/0
[r4-Tunnel0/0/0]ip add 10.1.2.2 24
[r4-Tunnel0/0/0]tunnel-protocol gre p2mp 
[r4-Tunnel0/0/0]source GigabitEthernet 0/0/0
[r4-Tunnel0/0/0]nhrp entry 10.1.2.1 16.1.1.1 register 
[r4-Tunnel0/0/0]nhrp entry 10.1.2.3 56.1.1.1 register 
[r4-Tunnel0/0/0]nhrp network-id 100

[r5]interface Tunnel 0/0/0
[r5-Tunnel0/0/0]ip address 10.1.2.3 24
[r5-Tunnel0/0/0]tunnel-protocol gre p2mp 
[r5-Tunnel0/0/0]source 56.1.1.1
[r5-Tunnel0/0/0]nhrp entry 10.1.2.1 16.1.1.1 register 
[r5-Tunnel0/0/0]nhrp entry 10.1.2.2 46.1.1.1 register
[r5-Tunnel0/0/0]nhrp network-id 100
[r5-Tunnel0/0/0]nhrp entry multicast dynamic 

第五步：ospf宣告

[r1]ospf 1 router-id 1.1.1.1
[r1-ospf-1]area 0
[r1-ospf-1-area-0.0.0.0]network 10.1.1.1 0.0.0.0
[r1-ospf-1-area-0.0.0.0]network 10.1.2.1 0.0.0.0
[r1-ospf-1-area-0.0.0.0]network 192.168.1.1 0.0.0.0

[r2]ospf 1 router-id 2.2.2.2
[r2-ospf-1]area 0
[r2-ospf-1-area-0.0.0.0]network 10.1.1.2 0.0.0.0
[r2-ospf-1-area-0.0.0.0]network 192.168.2.1 0.0.0.0

[r3]ospf 1 router-id 3.3.3.3
[r3-ospf-1]area 0
[r3-ospf-1-area-0.0.0.0]network 10.1.1.3 0.0.0.0
[r3-ospf-1-area-0.0.0.0]network 192.168.3.1 0.0.0.0

[r4]ospf 1 router-id 4.4.4.4
[r4-ospf-1]area 0
[r4-ospf-1-area-0.0.0.0]network 192.168.4.1 0.0.0.0
[r4-ospf-1-area-0.0.0.0]network 10.1.2.2 0.0.0.0

[r5]ospf 1 router-id 5.5.5.5
[r5-ospf-1]area 0
[r5-ospf-1-area-0.0.0.0]network 192.168.5.1 0.0.0.0
[r5-ospf-1-area-0.0.0.0]network 10.1.2.3 0.0.0.0

第六步：修改ospf工作方式

[r1]interface Tunnel 0/0/0
[r1-Tunnel0/0/0]ospf network-type broadcast
[r1]interface Tunnel 0/0/1
[r1-Tunnel0/0/1]ospf network-type broadcast 

[r2]int t0/0/0
[r2-Tunnel0/0/0]ospf network-type broadcast
[r2-Tunnel0/0/0]ospf dr-priority 0	修改dr选举为0

[r3]int t0/0/0
[r3-Tunnel0/0/0]ospf network-type broadcast 
[r3-Tunnel0/0/0]ospf dr-priority 0	修改dr选举为0

[r4]int t0/0/0
[r4-Tunnel0/0/0]ospf network-type broadcast

[r5]int t0/0/0
[r5-Tunnel0/0/0]ospf network-type broadcast