一，拓扑
二，要求
1，R6为ISP只能配置IP地址，R1-R5的环回为私有网段
2，R1/4/5为全连的MGRE结构，R1/2/3为星型的拓扑结构，
3，R1为中心站点所有私有网段可以互相通讯，私有网段使用osPF完成
三，配置
r1
IP配置：
r1interface GigabitEthernet 0/0/0
r1-GigabitEthernet0/0/0ip address 16.0.0.1 24
r1interface GigabitEthernet 0/0/1
r1-GigabitEthernet0/0/1ip address 17.0.0.1 24
r1interface LoopBack 0
r1-LoopBack0ip address 192.168.1.1 24
缺省路由：
r1ip route-static 0.0.0.0 0 16.0.0.2
r1ip route-static 0.0.0.0 0 17.0.0.2
隧道接口配置：
r1interface Tunnel 0/0/0
r1-Tunnel0/0/0ip address 10.1.1.1 24
r1-Tunnel0/0/0tunnel-protocol gre p2mp
r1-Tunnel0/0/0source 16.0.0.1
r1-Tunnel0/0/0ospf network-type broadcast //修改接口类型
r1-Tunnel0/0/0nhrp entry multicast dynamic//开启伪广播来实现OSPF的组播功能
隧道接口配置：
r1interface Tunnel 0/0/1
r1-Tunnel0/0/1shutdown //关闭接口，方便配置实现
r1-Tunnel0/0/1ip address 10.1.2.1 24
r1-Tunnel0/0/1tunnel-protocol gre p2mp
r1-Tunnel0/0/1source GigabitEthernet 0/0/1
r1-Tunnel0/0/1nhrp entry 10.1.2.2 46.0.0.1 register
r1-Tunnel0/0/1nhrp entry 10.1.2.3 56.0.0.1 register
r1-Tunnel0/0/1ospf network-type broadcast
OSPF配置：
r1ospf 1 router-id 1.1.1.1
r1-ospf-1are
r1-ospf-1area 0
r1-ospf-1-area-0.0.0.0net
r1-ospf-1-area-0.0.0.0network 10.1.1.0 0.0.0.255
r1-ospf-1-area-0.0.0.0network 10.1.2.0 0.0.0.255
r1-ospf-1-area-0.0.0.0network 192.168.1.0 0.0.0.255
r1interface Tunnel 0/0/1 //开启接口
r1-Tunnel0/0/1undo shutdown
r2
IP配置：
r2interface GigabitEthernet 0/0/0
r2-GigabitEthernet0/0/0ip address 26.0.0.1 24
r2interface LoopBack 0
r2-LoopBack0ip address 192.168.2.1 24
缺省路由：
r2ip route-static 0.0.0.0 0 26.0.0.2
隧道接口配置：
r2interface Tunnel 0/0/0
r2-Tunnel0/0/0ip address 10.1.1.2 24
r2-Tunnel0/0/0tunnel-protocol gre p2mp
r2-Tunnel0/0/0source GigabitEthernet 0/0/0
r2-Tunnel0/0/0nhrp entry 10.1.1.1 16.0.0.1 register
r2-Tunnel0/0/0ospf network-type broadcast
r2-Tunnel0/0/0ospf dr-priority 0
OSPF配置：
r2ospf 1 router-id 2.2.2.2
r2-ospf-1area 0
r2-ospf-1-area-0.0.0.0network 10.1.1.0 0.0.0.255
r2-ospf-1-area-0.0.0.0network 192.168.2.0 0.0.0.255
r3
IP配置：
r3interface GigabitEthernet 0/0/0
r3-GigabitEthernet0/0/0ip address 36.0.0.1 24
r3interface LoopBack 0
r3-LoopBack0ip address 192.168.3.1 24
缺省路由：
r3ip route-static 0.0.0.0 0 36.0.0.2
隧道接口配置：
r3interface Tunnel 0/0/0
r3-Tunnel0/0/0ip address 10.1.1.3 24
r3-Tunnel0/0/0tunnel-protocol gre p2mp
r3-Tunnel0/0/0source GigabitEthernet 0/0/0
r3-Tunnel0/0/0nhrp entry 10.1.1.1 16.0.0.1 register
r3-Tunnel0/0/0ospf network-type broadcast
OSPF配置：
r3ospf 1 router-id 3.3.3.3
r3-ospf-1area 0
r3-ospf-1-area-0.0.0.0network 192.168.3.0 0.0.0.255
r3-ospf-1-area-0.0.0.0network 10.1.1.0 0.0.0.255
r4
IP配置：
r4interface GigabitEthernet 0/0/0
r4-GigabitEthernet0/0/0ip address 46.0.0.1 24
r4interface LoopBack 0
r4-LoopBack0ip address 192.168.4.1 24
缺省路由：
r4ip route-static 0.0.0.0 0 46.0.0.2
隧道接口配置：
r4interface Tunnel 0/0/0
r4-Tunnel0/0/0shutdown
r4-Tunnel0/0/0ip address 10.1.2.2 24
r4-Tunnel0/0/0tunnel-protocol gre p2mp
r4-Tunnel0/0/0source GigabitEthernet 0/0/0
r4-Tunnel0/0/0nhrp entry 10.1.2.1 17.0.0.1 register
r4-Tunnel0/0/0nhrp entry 10.1.2.3 56.0.0.1 register
r4-Tunnel0/0/0ospf network-type broadcast
OSPF配置：
r4ospf 1 router-id 4.4.4.4
r4-ospf-1area 0
r4-ospf-1-area-0.0.0.0network 192.168.4.0 0.0.0.255
r4-ospf-1-area-0.0.0.0network 10.1.2.0 0.0.0.255
开启接口
r4interface Tunnel 0/0/0
r4-Tunnel0/0/0undo shutdown
r5IP配置：
r5interface GigabitEthernet 0/0/0
r5-GigabitEthernet0/0/0ip address 56.0.0.1 24
r5interface LoopBack 0
r5-LoopBack0ip address 192.168.5.1 24
缺省路由：
r5ip route-static 0.0.0.0 0 56.0.0.2
隧道接口配置：
r5interface Tunnel 0/0/0
r5-Tunnel0/0/0shutdown
r5-Tunnel0/0/0ip address 10.1.2.3 24
r5-Tunnel0/0/0tunnel-protocol gre p2mp
r5-Tunnel0/0/0source GigabitEthernet 0/0/0
r5-Tunnel0/0/0nhrp entry 10.1.2.1 17.0.0.1 register
r5-Tunnel0/0/0nhrp entry 10.1.2.2 46.0.0.1 register
r5-Tunnel0/0/0ospf network-type broadcast
OSPF配置：
r5ospf 1 router-id 5.5.5.5
r5-ospf-1area 0
r5-ospf-1-area-0.0.0.0network 192.168.5.0 0.0.0.255
r5-ospf-1-area-0.0.0.0network 10.1.2.0 0.0.0.255
r5interface Tunnel 0/0/0
r5-Tunnel0/0/0undo shutdown
r6
IP配置：
r6interface GigabitEthernet 4/0/0
r6-GigabitEthernet4/0/0ip address 17.0.0.2 24
r6interface GigabitEthernet 0/0/0
r6-GigabitEthernet0/0/0ip address 16.0.0.2 24
r6interface GigabitEthernet 0/0/1
r6-GigabitEthernet0/0/1ip address 26.0.0.2 24
r6interface GigabitEthernet 0/0/2
r6-GigabitEthernet0/0/2ip address 36.0.0.2 24
r6interface GigabitEthernet 2/0/0
r6-GigabitEthernet2/0/0ip address 46.0.0.2 24
r6interface GigabitEthernet 3/0/0
r6-GigabitEthernet3/0/0ip address 56.0.0.2 24
四，测试
