一、实验拓扑图

二、实验需求

1.如图搭建网络拓扑，所有路由器各自创建一个环回接口，合理规划IP地址

2.R1-R2-R3-R4-R6之间使用OSPF协议，R4-R5-R6之间使用RIP协议

3.R1环回重发布方式引入OSPF网络

4.R4/R6上进行双点双向重发布

5.分析网络中出现路由环路的原因

6.路由优化

三、实验步骤

1.配置接口IP地址及各个环回

AR1

[Huawei]sysname AR1
[AR1-GigabitEthernet0/0/0]ip add 12.1.1.1 24
[AR1-LoopBack0]ip add 1.1.1.1 32

AR2

[Huawei]sysname AR2
[AR2-GigabitEthernet0/0/1]ip add 12.1.1.1 24
[AR2-GigabitEthernet0/0/0]ip add 23.1.1.1 24
[AR2-LoopBack0]ip add 2.2.2.2 32

AR3

[Huawei]sysname AR3
[AR3-GigabitEthernet0/0/1]ip add 23.1.1.2 24
[AR3-GigabitEthernet0/0/0]ip add 34.1.1.1 24 
[AR3-LoopBack0]ip add 3.3.3.3 32
[AR3-GigabitEthernet0/0/2]ip add 36.1.1.2 24

AR4

[Huawei]sysname AR4
[AR4-GigabitEthernet0/0/0]ip add 45.1.1.1 24
[AR4-GigabitEthernet0/0/1]ip add 34.1.1.2 24
[AR4-LoopBack0]ip add 4.4.4.4 32

AR5

[Huawei]sysname AR5
[AR5-GigabitEthernet0/0/0]ip add 56.1.1.1 24
[AR5-GigabitEthernet0/0/1]ip add 45.1.1.2 24
[AR5-LoopBack0]ip add 5.5.5.5 32

AR6

[Huawei]sysname AR6
[AR6-GigabitEthernet0/0/1]ip add 56.1.1.2 24
[AR6-GigabitEthernet0/0/0]ip add 36.1.1.1 24
[AR6-LoopBack0]ip add 6.6.6.6 32

 2.R1-R2-R3-R4-R6之间启用OSPF协议，R4-R5-R6之间使用RIP协议

R1-R2-R3-R4-R6

[AR1]ospf 100 router-id 91.1.1.1
[AR1-ospf-100]area 0	
[AR1-ospf-100-area-0.0.0.0]network 12.1.1.1 0.0.0.0

[AR2]ospf 100 router-id 92.2.2.2
[AR2-ospf-100]area 0	
[AR2-ospf-100-area-0.0.0.0]network 2.2.2.2 0.0.0.0	
[AR2-ospf-100-area-0.0.0.0]network 12.1.1.2 0.0.0.0
[AR2-ospf-100-area-0.0.0.0]network 23.1.1.1 0.0.0.0

[AR3]ospf 100 router-id 93.3.3.3
[AR3-ospf-100]area 0	
[AR3-ospf-100-area-0.0.0.0]network 23.1.1.2 0.0.0.0	
[AR3-ospf-100-area-0.0.0.0]network 34.1.1.1 0.0.0.0	
[AR3-ospf-100-area-0.0.0.0]network 36.1.1.2 0.0.0.0	
[AR3-ospf-100-area-0.0.0.0]network 3.3.3.3 0.0.0.0

[AR4]ospf 100 router-id 94.4.4.4
[AR4-ospf-100]area 0	
[AR4-ospf-100-area-0.0.0.0]network 34.1.1.2 0.0.0.0
[AR4-ospf-100-area-0.0.0.0]network 4.4.4.4 0.0.0.0

[AR6]ospf 100 router-id 96.6.6.6
[AR6-ospf-100]area 0
[AR6-ospf-100-area-0.0.0.0]network 36.1.1.1 0.0.0.0
[AR6-ospf-100-area-0.0.0.0]network 6.6.6.6 0.0.0.0

R4-R5-R6

[AR4]rip 100
[AR4-rip-100]version 2	
[AR4-rip-100]network 45.0.0.0

[AR5]rip 100
[AR5-rip-100]version 2	
[AR5-rip-100]network 5.0.0.0	
[AR5-rip-100]network 45.0.0.0	
[AR5-rip-100]network 56.0.0.0

[AR6]rip 100
[AR6-rip-100]version 2	
[AR6-rip-100]network 56.0.0.0

 3.R1环回重发布方式引入OSPF网络

[AR1]ospf 100	
[AR1-ospf-100]import-route direct

 4.R4/R6上进行双点双向重发布

[AR6]ospf 100	
[AR6-ospf-100]import-route rip 100
[AR6]rip 100
[AR6-rip-100]import-route ospf 100

[AR4]rip 100	
[AR4-rip-100]import-route ospf 100
[AR4]ospf 100
[AR4-ospf-100]import-route rip 100

 5.分析网络中出现路由环路的原因

产生环路的原因是因为 RIP和OSPF的优先级不同，RIP的优先级为100，OSPF的优先级为10和150，通过重分布进来产生的五类LSA的优先级为150，通过R4和R5的重发布后优先级会变为RIP的优先级，R5学习到后会把1.1.1.1 32这条路由发给R6，R6又会发给R3，但是此时R3中有关于1.1.1.1 32这条路由，就会导致环路，我们需要做的就是在重发布时修改1.1.1.1 32这条路由的优先级，使得R3不会学习重发布里面的路由

[AR4]ip ip-prefix B4 permit 1.1.1.1 32	
[AR4]route-policy wy permit node 12	
[AR4-route-policy]if-match ip-prefix B4
[AR4-route-policy]apply preference 160
	
[AR6]ip ip-prefix A4 permit 1.1.1.0 24	
[AR6]route-policy wjk permit node 12	
[AR6-route-policy]if-match ip-prefix A4	
[AR6-route-policy]apply preference 160

6.路由优化

修改种子度量值

[AR4]ip ip-prefix B1 permit 36.1.1.0 24	
[AR4]ip ip-prefix B2 permit 6.6.6.6 32	
[AR4]ip ip-prefix B3 permit 56.1.1.0 24	
[AR4]route-policy wy permit node 10
Info: New Sequence of this List.	
[AR4-route-policy]if-match ip-prefix B1	
[AR4-route-policy]apply cost 99
[AR4-route-policy]q	
[AR4]route-policy wy permit node 20	
[AR4-route-policy]if-match ip-prefix B2	
[AR4-route-policy]apply cost 99
[AR4-route-policy]q	
[AR4]route-policy wy permit node 30
Info: New Sequence of this List.	
[AR4-route-policy]if-match ip-prefix B3	
[AR4-route-policy]apply cost 99
[AR4-route-policy]q	
[AR4]route-policy wy permit node 40
Info: New Sequence of this List.
[AR4-route-policy]q
[AR4]rip 100	
[AR4-rip-100]import-route ospf 100 route-policy wy

[AR6]ip ip-prefix A1 permit 45.1.1.0 24
[AR6]ip ip-prefix A2 permit 4.4.4.4 32	
[AR6]ip ip-prefix A3 permit 34.1.1.0 24	
[AR6]route-policy wjk permit node 10
Info: New Sequence of this List.	
[AR6-route-policy]if-match ip-prefix A1	
[AR6-route-policy]apply cost 99
[AR6-route-policy]q
[AR6]route-policy wjk permit node 20
Info: New Sequence of this List.	
[AR6-route-policy]if-match ip-prefix A2	
[AR6-route-policy]apply cost 99
[AR6-route-policy]q	
[AR6]route-policy wjk permit node 30
Info: New Sequence of this List.	
[AR6-route-policy]if-match ip-prefix A3	
[AR6-route-policy]apply cost 99
[AR6-route-policy]q	
[AR6]route-policy wjk permit node 40
Info: New Sequence of this List.

7.全网通