配置地址
【R1】
[r1-GigabitEthernet0/0/0]ip address 116.0.0.1 24
[r1-GigabitEthernet0/0/1]ip address 16.0.0.1 24
[r1-LoopBack0]ip address 192.168.1.1 24
【R2】
[r2-GigabitEthernet0/0/0]ip address 26.0.0.1 24
[r2-LoopBack0]ip address 192.168.2.1 24
【R3】
[r3-GigabitEthernet0/0/0]ip address 36.0.0.1 24
[r3-LoopBack0]ip address 192.168.3.1 24
【R4】
[r4-GigabitEthernet0/0/0]ip address 46.0.0.1 24
[r4-LoopBack0]ip address 192.168.4.1 24
【R5】
[r5-GigabitEthernet0/0/0]ip address 56.0.0.1 24
[r5-LoopBack0]ip address 192.168.5.1 24
【R6】
[ISP-GigabitEthernet2/0/0]ip address 46.0.0.2 24
[ISP-GigabitEthernet0/0/0]ip address 116.0.0.2 24
[ISP-GigabitEthernet0/0/1]ip address 116.0.0.2 24
[ISP-GigabitEthernet0/0/2]ip address 56.0.0.2 24
[ISP-GigabitEthernet3/0/0]ip address 26.0.0.2 24
[ISP-GigabitEthernet4/0/0]ip address 36.0.0.2 24
配缺省
[r1]ip route-static 0.0.0.0 0 116.0.0.2
[r1]ip route-static 0.0.0.0 0 16.0.0.2
[r2]ip route-static 0.0.0.0 0 26.0.0.2
[r3]ip route-static 0.0.0.0 0 36.0.0.2
[r4]ip route-static 0.0.0.0 0 46.0.0.2
[r5]ip route-static 0.0.0.0 0 56.0.0.2
验证
R1/R4/R5为全连的MGRE结构
[r1]interface t0/0/0
[r1-Tunnel0/0/0]ip address 192.168.6.1 24
[r1-Tunnel0/0/0]tunnel-protocol gre p2mp
[r1-Tunnel0/0/0]source 16.0.0.1
[r1-Tunnel0/0/0]nhrp network-id 100
[r1-Tunnel0/0/0]nhrp entry multicast dynamic
[r4]interface t0/0/0
[r4-Tunnel0/0/0]ip address 192.168.6.2 24
[r4-Tunnel0/0/0]tunnel-protocol gre p2mp
[r4-Tunnel0/0/0]source 46.0.0.1
[r4-Tunnel0/0/0]nhrp network-id 100
[r4-Tunnel0/0/0]nhrp entry multicast dynamic
[r5]interface t0/0/0
[r5-Tunnel0/0/0]ip address 192.168.6.3 24
[r5-Tunnel0/0/0]tunnel-protocol gre p2mp
[r5-Tunnel0/0/0]source 56.0.0.1
[r5-Tunnel0/0/0]nhrp network-id 100
[r5-Tunnel0/0/0]nhrp entry multicast dynamic
上报信息到中心
[r1-Tunnel0/0/0]nhrp entry 192.168.6.2 46.0.0.1 register
[r1-Tunnel0/0/0]nhrp entry 192.168.6.3 56.0.0.1 register
[r4-Tunnel0/0/0]nhrp entry 192.168.6.3 56.0.0.1 register
([r4-Tunnel0/0/0]nhrp entry 192.168.6.1 16.0.0.1 registe)可敲可不敲,R1认证后R4不敲也可以
([r5-Tunnel0/0/0]nhrp entry 192.168.6.1 16.0.0.1 register
[r5-Tunnel0/0/0]nhrp entry 192.168.6.2 46.0.0.1 register)
R1/R2/R3为星型拓扑,R1为中心站点
[r1]interface t0/0/1
[r1-Tunnel0/0/1]ip address 192.168.7.1 24
[r1-Tunnel0/0/1]tunnel-protocol gre p2mp
[r1-Tunnel0/0/1]source 116.0.0.1
[r1-Tunnel0/0/1]nhrp network-id 110
[r1-Tunnel0/0/1]nhrp entry multicast dynamic
[r2]interface t0/0/1
[r2-Tunnel0/0/1]ip address 192.168.7.2 24
[r2-Tunnel0/0/1]tunnel-protocol gre p2mp
[r2-Tunnel0/0/2]source GigabitEthernet 0/0/0(出接口)
[r2-Tunnel0/0/1]nhrp network-id 110
[r2-Tunnel0/0/1]nhrp entry 192.168.7.1 116.0.0.1 register (中心站点)
[r3]interface t0/0/1
[r3-Tunnel0/0/1]ip address 192.168.7.3 24
[r3-Tunnel0/0/1]tunnel-protocol gre p2mp
[r3-Tunnel0/0/2]source GigabitEthernet 0/0/0(出接口)
[r3-Tunnel0/0/1]nhrp network-id 110
[r3-Tunnel0/0/1]nhrp entry 192.168.7.1 116.0.0.1 register (中心站点)
使用OSPF完成所有私有网段相互通讯
[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 192.168.6.0 0.0.0.255
[r1-ospf-1-area-0.0.0.0]network 192.168.7.0 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 192.168.7.0 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 192.168.7.0 0.0.0.255
[r4]ospf 1 router-id 4.4.4.4
[r4-ospf-1]area 0
[r4-ospf-1-area-0.0.0.0]network 192.168.4.0 0.0.0.255
[r4-ospf-1-area-0.0.0.0]network 192.168.6.0 0.0.0.255
[r5]ospf 1 router-id 5.5.5.5
[r5-ospf-1]area 0
[r5-ospf-1-area-0.0.0.0]network 192.168.5.0 0.0.0.255
[r5-ospf-1-area-0.0.0.0]network 192.168.6.0 0.0.0.255
问题一:在R1/R4/R5中,R1只和R4或R5建立了邻居关系,我们要建立全连MGRE,并且因为MGRE构建的网络类似于一个NBMA的网络,所以不支持广播和组播,因此要开启伪广播
解决:
(1)R1/R4/R5的全连MGRE的修改
[r1]interface t0/0/0
[r1-Tunnel0/0/0]ospf network-type broadcast 将接口类型改为broadcast
[r1-Tunnel0/0/0]nhrp entry multicast dynamic 开启伪广播
[r4]interface t00/0/0
[r4-Tunnel0/0/0]ospf network-type broadcast
[r1-Tunnel0/0/0]nhrp entry multicast dynamic
[r5]interface t00/0/0
[r5-Tunnel0/0/0]ospf network-type broadcast
[r1-Tunnel0/0/0]nhrp entry multicast dynamic
问题二: 在R1/R2/R3中,R1只和R2或R3建立了邻居关系,R1/R2/R3为星型拓扑结构,我们可以将接口类型改为P2MP。假设R1为中心,R2,D3要放弃DR/BDR的选举。
解决:
[r1]interface t00/0/1
[r1-Tunnel0/0/1]ospf network-type P2MP
[r2]interface t00/0/1
[r2-Tunnel0/0/1]ospf network-type P2MP
[r2-Tunnel0/0/1]ospf dr-priority 0
[r3]interface t00/0/1
[r3-Tunnel0/0/1]ospf network-type P2MP
[r3-Tunnel0/0/1]ospf dr-priority 0