一、思路；

1.增加不优选路开销解决选路不佳问题

2.用增加开销的方式使R1 不将ASBR传的R7传给另一台ASBR解决R1、R2、R3、R4pingR7环回环路

二、操作

------IP地址配置如图

1.ospf及rip的宣告

rip：

[r1]rip 1
[r1-rip-1]version 2
[r1-rip-1]network 1.0.0.0
[r1-rip-1]network 12.0.0.0
[r1-rip-1]network 13.0.0.0

[r2]rip 1
[r2-rip-1]version 2
[r2-rip-1]network 12.0.0.0
[r2-rip-1]network 2.0.0.0

[r3]rip 1
[r3-rip-1]vers
[r3-rip-1]version 2
[r3-rip-1]net
[r3-rip-1]network 13.0.0.0

OSPF：

[r3]ospf 1
[r3-ospf-1]a 0
[r3-ospf-1-area-0.0.0.0]network 34.1.1.2 0.0.0.0
[r3-ospf-1-area-0.0.0.0]network 3.3.3.3 0.0.0.0

[r4]ospf 1
[r4-ospf-1]a 0
[r4-ospf-1-area-0.0.0.0]network 24.1.1.2 0.0.0.0
[r4-ospf-1-area-0.0.0.0]network 34.1.1.1 0.0.0.0
[r4-ospf-1-area-0.0.0.0]network 4.4.4.4 0.0.0.0
[r4-ospf-1-area-0.0.0.0]network 45.1.1.1 0.0.0.0

[r5]ospf 1
[r5-ospf-1]a 0
[r5-ospf-1-area-0.0.0.0]network 45.1.1.2 0.0.0.0
[r5-ospf-1-area-0.0.0.0]network 56.1.1.1 0.0.0.0
[r5-ospf-1-area-0.0.0.0]network 5.5.5.5 0.0.0.0

[r6]ospf 1
[r6-ospf-1]a 0
[r6-ospf-1-area-0.0.0.0]network 56.1.1.2 0.0.0.0
[r6-ospf-1-area-0.0.0.0]network 67.1.1.1 0.0.0.0
[r6-ospf-1-area-0.0.0.0]network 6.6.6.6 0.0.0.0

[r7]ospf 1
[r7-ospf-1]a 0
[r7-ospf-1-area-0.0.0.0]network 7.7.7.7 0.0.0.0
[r7-ospf-1-area-0.0.0.0]network 67.1.1.2 0.0.0.0

2.重发布

R7：

[r7]ospf 1
[r7-ospf-1]import-route direct

R2、R3双向重发布：

[r2-ospf-1]import-route rip 1
[r2-ospf-1]rip 1
[r2-rip-1]import-route ospf 1
[r2-rip-1]

[r3]ospf 1
[r3-ospf-1]import-route rip 1
[r3-ospf-1]rip 1
[r3-rip-1]import-route ospf 1

3.解决环路

[r2] ip ip-prefix a permit 7.7.7.0 24

[r2]route-policy huawei permit node 10
[r2-route-policy]if-match ip-prefix a
[r2-route-policy]apply cost 14
[r2-route-policy]q

[r3] ip ip-prefix a permit 7.7.7.0 24

[r3]route-policy huawei permit node 10
[r3-route-policy]if-match ip-prefix a
[r3-route-policy]apply cost 14
[r3-route-policy]q

[r2]ospf 1
[r2-ospf-1]import-route rip 1 route-policy huawei

[r3]ospf 1
[r3-ospf-1]import-route rip 1 route-policy huawei

4.解决选路不佳

R1

[r1]ip ip-prefix aa permit 24.1.1.0 24
[r1]ip ip-prefix bb permit 34.1.1.0 24
[r1]ip ip-prefix bb permit 3.3.3.3 32
[r1]int g0/0/0
[r1-GigabitEthernet0/0/0]rip metricin ip-prefix aa 2
[r1-GigabitEthernet0/0/0]int g0/0/1
[r1-GigabitEthernet0/0/1]rip metricin ip-prefix bb 2
[r1-GigabitEthernet0/0/1]