步骤:
1.给路由器配置IP,环回,给边界路由器写缺省
[R1]ip route-static 0.0.0.0 0 14.1.1.2
[R2]ip route-static 0.0.0.0 0 24.1.1.2
[R3]ip route-static 0.0.0.0 0 34.1.1.2
2.R1,R2,R3建立MGRE环境
R1为中心站点
[R1]interface Tunnel 0/0/0
[R1-Tunnel0/0/0]tunnel-protocol gre p2mp
[R1-Tunnel0/0/0]source 14.1.1.1
[R1-Tunnel0/0/0]nhrp entry multicast dynamic
[R1-Tunnel0/0/0]nhrp network-id 100
[R1-Tunnel0/0/0]ip address 10.1.1.1 24
R2:
[R2]interface Tunnel 0/0/0
[R2-Tunnel0/0/0]ip address 10.1.1.2 24
[R2-Tunnel0/0/0]tunnel-protocol gre p2mp
[R2-Tunnel0/0/0]source s4/0/0
[R2-Tunnel0/0/0]nhrp n
[R2-Tunnel0/0/0]nhrp network-id 100
[R2-Tunnel0/0/0]nhrp entry 10.1.1.1 14.1.1.1 register
R3:
3.R1,R2,R3启ospf协议
[R1]ospf 1 router-id 1.1.1.1
[R1-ospf-1]area 0
[R1-ospf-1-area-0.0.0.0]network 192.168.1.0 0.0.0.255
[R1-ospf-1-area-0.0.0.0]network 10.1.1.0 0.0.0.255
[R2]ospf 1 router-id 2.2.2.2
[R2-ospf-1]area 0
[R2-ospf-1-area-0.0.0.0]network 192.168.2.0 0.0.0.255
[R2-ospf-1-area-0.0.0.0]network 10.1.1.0 0.0.0.255
[R3]ospf 1 router-id 3.3.3.3
[R3-ospf-1]area 0
[R3-ospf-1-area-0.0.0.0]network 192.168.3.0 0.0.0.255
[R3-ospf-1-area-0.0.0.0]network 10.1.1.0 0.0.0.255
4.修改tunnel接口方式为broadcast
[R1]int Tunnel 0/0/0
[R1-Tunnel0/0/0]ospf network-type broadcast
[R2]int Tunnel 0/0/0
[R2-Tunnel0/0/0]ospf network-type broadcast
[R3]int Tunnel 0/0/0
[R3-Tunnel0/0/0]ospf network-type broadcast
此时R1为BDR,因此要修改R1的优先级
5.修改R1的优先级
[R1]int s4/0/0
[R1-Serial4/0/0]ospf dr-priority 200
6.实验结果