一：实验要求
1、R4为ISP，其上只能配置IP地址，R4与其所有直连设备间均使用公有IP
2、R3-R5/6/7为MGRE环境，R3为中心站点
3、整个OSPF环境IP基于R4的环回
4、所有设备均可访问R4的环回
5、减少LSA的更新量，加快收敛，保障更新安全
6、全网可达
二：实验分析
1：子网划分
基于172.16.0.0/16划分网段
172.16.0.0/16
172.16.0.0/19 area 0
172.16.0.0/24 p2p骨干 172.16.1.0/24 MA骨干
172.16.1.0/29 T通道
172.16.2.0/24 R5环回
172.16.3.0/24 R6环回
172.16.4.0/24 R7环回
172.16.5.0/24 R4环回
172.16.32.0/19 area 1
172.16.32.0/24 p2p
172.16.33.0/24 MA
172.16.33.0/29
172.16.34.0/24 R1环回
172.16.35.0/24 R2环回
172.16.36.0/24 R3环回
172.16.64.0/19 area 2 172.16.65.0/24 p2p****172.16.64.0/24 MA
172.16.64.0/30
172.16.64.4/30
172.16.66.0/24 R11环回
172.16.96.0/19 area 3
172.16.96.0/24 MA
172.16.96.0/30
172.16.96.4/30
172.16.97.0/24 p2p
172.16.98.0/24 R8环回
172.16.128.0/19 area 4
172.16.128.0/24 MA
172.16.128.0/30
172.16.129.0/24 p2p
172.16.130.0/24 R9环回
172.16.131.0/24 R10环回
172.16.160.0/19 rip
172.16.160.0/24 MA
172.16.161.0/24 P2P
172.16.162.0/24 R12环回
172.16.163.0/24 R12环回
2、实验拓扑
三：实验配置
配置IP地址
[r1-GigabitEthernet0/0/0]ip address 172.16.33.1 29
[r1-LoopBack0]ip addres9999s 172.16.34.1 24
[r2-GigabitEthernet0/0/0]ip address 172.16.33.2 29
[r2-LoopBack0]ip address 172.16.35.1 24
[r3-GigabitEthernet0/0/0]ip address 172.16.33.3 29
[r3-Serial4/0/0]ip address 34.1.1.1 24
[r3-LoopBack0]ip address 172.16.36.1 24
[r4-Serial4/0/0]ip address 34.1.1.2 24
[r4-Serial4/0/1]ip address 45.1.1.2 24
[r4-Serial3/0/0]ip address 46.1.1.2 24
[r4-GigabitEthernet0/0/0]ip address 47.1.1.2 24
[r4-LoopBack0]ip address 172.16.5.1 24
[r5-Serial4/0/0]ip address 45.1.1.1 24
[r5-LoopBack0]ip address 172.16.2.1 24
[r6-Serial4/0/0]ip address 46.1.1.1 24
[r6-GigabitEthernet0/0/0]ip address 172.16.64.1 30
[r6-LoopBack0]ip address 172.16.3.1 24
[r7-GigabitEthernet0/0/0]ip address 47.1.1.1 24
[r7-GigabitEthernet0/0/1]ip address 172.16.96.1 30
[r7-LoopBack0]ip address 172.16.4.1 24
[r8-GigabitEthernet0/0/0]ip address 172.16.96.2 30
[r8-GigabitEthernet0/0/1]ip address 172.16.96.5 30
[r8-LoopBack0]ip address 172.16.98.1 24
[r9-GigabitEthernet0/0/0]ip address 172.16.96.6 30
[r9-GigabitEthernet0/0/1]ip address 172.16.128.1 30
[r9-LoopBack0]ip address 172.16.130.1 24
[r10-GigabitEthernet0/0/0]ip address 172.16.128.2 30
[r10-LoopBack0]ip address 172.16.131.1 24
[r11-GigabitEthernet0/0/0]ip address 172.16.64.2 30
[r11-GigabitEthernet0/0/1]ip address 172.16.64.5 30
[r11-LoopBack0]ip address 172.16.66.1 24
[r12-GigabitEthernet0/0/0]ip address 172.16.64.6 30
[r12-LoopBack0]ip address 172.16.162.1 24
[r12-LoopBack1]ip address 172.16.163.1 24
配置MGRE
写缺省让公网以及通道连接，修改通道ospf优先级以及MGRE修改为BMA网络，或者修改成p2mp
网络就不用选举来修改ospf优先级
[r3]ip route-static 0.0.0.0 0 34.1.1.2
[r5]ip route-static 0.0.0.0 0 45.1.1.2
[r6]ip route-static 0.0.0.0 0 46.1.1.2
[r7]ip route-static 0.0.0.0 0 47.1.1.2
[r3-Tunnel0/0/0]ospf dr-priority 100
[r3-Tunnel0/0/0]ospf network-type broadcast
[r5-Tunnel0/0/0]ospf dr-priority 0
[r5-Tunnel0/0/0]ospf network-type broadcast
[r6-Tunnel0/0/0]ospf dr-priority 0
[r6-Tunnel0/0/0]ospf network-type broadcast
[r7-Tunnel0/0/0]ospf dr-priority 0
[r7-Tunnel0/0/0]ospf network-type broadcast
宣告ospf和rip
r12路由器用单点单向重发布。r9路由器做一个单点单向重发布，r10路由器写一条缺省指向R9接
口，或者在R9进程2下放一个缺省
[r9-ospf-1]import-route ospf 2
[r12-ospf-1]import-route rip 1
[r10]ip route-static 0.0.0.0 0 172.16.128.1
r3/5/6/7路由器上做一个easy ip 使得其他路由器能访问r4的环回
[r3]acl 2000
[r3-acl-basic-2000]rule permit source 172.16.0.0 0.0.0.255
[r3-Serial4/0/0]nat outbound 2000
[r7]acl 2000
[r7-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[r7-GigabitEthernet0/0/0]nat outbound 2000
[r6]acl 2000
[r6-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[r6-Serial4/0/0]nat outbound 2000
[r5]acl 2000
[r5-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[r5-Serial4/0/0]nat outbound 2000
路由汇总以及空接口
[r3-ospf-1-area-0.0.0.1]abr-summary 172.16.32.0 255.255.224.0
[r6-ospf-1-area-0.0.0.2]abr-summary 172.16.64.0 255.255.224.0
[r7-ospf-1-area-0.0.0.3]abr-summary 172.16.96.0 255.255.224.0
[r9-ospf-1]asbr-summary 172.16.128.0 255.255.224.0
[r12-ospf-1]asbr-summary 172.16.160.0 255.255.224.0
[r3]ip route-static 172.16.32.0 19 NULL 0
[r6]ip route-static 172.16.64.0 19 NULL 0
[r7]ip route-static 172.16.96.0 19 NULL 0
[r9]ip route-static 172.16.128.0 19 NULL 0
[r12]ip route-static 172.16.160.0 19 NULL 0
做特殊区域减少LSA
[r1-ospf-1-area-0.0.0.1]stub
[r2-ospf-1-area-0.0.0.1]stub
[r3-ospf-1-area-0.0.0.1]stub no-summary
[r6-ospf-1-area-0.0.0.2]nssa no-summary
[r11-ospf-1-area-0.0.0.2]nssa
[r12-ospf-1-area-0.0.0.2]nssa
[r7-ospf-1-area-0.0.0.3]nssa no-summary
[r8-ospf-1-area-0.0.0.3]nssa
[r9-ospf-1-area-0.0.0.3]nssa
加快收敛
[r1-GigabitEthernet0/0/0]ospf timer hello 5
[r2-GigabitEthernet0/0/0]ospf timer hello 5
[r3-GigabitEthernet0/0/0]ospf timer hello 5
区域认证
[r1-ospf-1-area-0.0.0.1]authentication-mode simple plain 123456
[r2-ospf-1-area-0.0.0.1]authentication-mode simple plain 123456
[r3-ospf-1-area-0.0.0.1]authentication-mode simple plain 123456
四、测试
所以用户可以r4 环回
全网可达
