实验要求：
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，全网可达
实验配置
AR1
interface GigabitEthernet0/0/0
ip address 12.1.1.1 255.255.255.0
interface LoopBack0
ip address 1.1.1.1 255.255.255.0
ospf 1
import-route direct
area 0.0.0.0
network 12.1.1.1 0.0.0.0
AR2
interface GigabitEthernet0/0/0
ip address 12.1.1.2 255.255.255.0
interface GigabitEthernet0/0/1
ip address 23.1.1.1 255.255.255.0
interface LoopBack0
ip address 2.2.2.2 255.255.255.0
ospf 1
area 0.0.0.0
network 2.2.2.2 0.0.0.0
network 12.1.1.2 0.0.0.0
network 23.1.1.1 0.0.0.0
AR3
interface GigabitEthernet0/0/0
ip address 34.1.1.1 255.255.255.0
interface GigabitEthernet0/0/1
ip address 23.1.1.2 255.255.255.0
interface GigabitEthernet0/0/2
ip address 36.1.1.1 255.255.255.0
interface LoopBack0
ip address 3.3.3.3 255.255.255.0
ospf 1
area 0.0.0.0
network 3.3.3.3 0.0.0.0
network 23.1.1.2 0.0.0.0
network 34.1.1.1 0.0.0.0
network 36.1.1.1 0.0.0.0
AR4
interface GigabitEthernet0/0/0
ip address 34.1.1.2 255.255.255.0
interface GigabitEthernet0/0/1
ip address 45.1.1.1 255.255.255.0
interface LoopBack0
ip address 4.4.4.4 255.255.255.0
ip ip-prefix r-o index 10 permit 6.6.6.6 32
ip ip-prefix r-o index 20 permit 65.1.1.0 24
route-policy r-o permit node 10
if-match ip-prefix r-o
apply cost 10
route-policy r-o permit node 20
ospf 1
import-route rip 100 route-policy r-o
area 0.0.0.0
network 4.4.4.4 0.0.0.0
network 34.1.1.2 0.0.0.0
rip 100
undo summary
version 2
network 45.0.0.0
import-route ospf 1
AR5
interface GigabitEthernet0/0/0
ip address 65.1.1.2 255.255.255.0
rip metricin 2001 5
interface GigabitEthernet0/0/1
ip address 45.1.1.2 255.255.255.0
interface LoopBack0
ip address 5.5.5.5 255.255.255.0
rip 1
rip 100
undo summary
version 2
network 45.0.0.0
network 65.0.0.0
network 5.0.0.0
acl number 2000
rule 5 deny source 45.1.1.0 0
rule 10 permit
acl number 2001
rule 5 permit source 36.1.1.0 0
AR6
interface GigabitEthernet0/0/0
ip address 65.1.1.1 255.255.255.0
rip metricout 2000 5
interface GigabitEthernet0/0/1
interface GigabitEthernet0/0/2
ip address 36.1.1.2 255.255.255.0
interface NULL0
interface LoopBack0
ip address 6.6.6.6 255.255.255.0
ospf 1
import-route rip 100 route-policy 1.1.1.1
area 0.0.0.0
network 6.6.6.6 0.0.0.0
network 36.1.1.2 0.0.0.0
rip 100
undo summary
version 2
network 65.0.0.0
import-route ospf 1
route-policy 1.1.1.1 permit node 10
if-match ip-prefix 1.1.1.1
apply cost 5
route-policy 1.1.1.1 permit node 20
ip ip-prefix 1.1.1.1 index 10 permit 1.1.1.1 32
acl number 2000
rule 5 permit source 34.1.1.0 0
测试
R1-R2-R3-R4-R6之间使用OSPF协议
R4-R5-R6之间使用RIP协议
R1环回重发布方式引入OSPF网络
R4/R6上进行双点双向重发布
分析网络中出现路由环路的原因
路由回馈导致路由环路
R3
R4 
R5 
R6
R3通过R6学习R1环回1.1.1.1
R4通过R3学习R1环回1.1.1.1
R5通过R4学习R1环回1.1.1.1
R6通过R5学习R1环回1.1.1.1
此时已出现路由环路
路由优化
全网可达
