OSPF综合
一、实验拓扑
二、实验需求
1、R4为ISP,其上只配置IP地址;R4与其他所直连设备间均使用公有IP;
2、R3-R5、R6、R7为MGRE环境,R3为中心站点;
3、整个OSPF环境IP基于172.16.0.0/16划分;除了R12有两个环回,其他路由器均有一个环回IP
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;
三、实验思路
1.基础网络搭建:
首先为所有设备配置IP地址,确保物理层面的连通性。
为R3、R5、R6、R7配置静态默认路由指向R4,实现公网通信基础。
配置MGRE隧道(GRE P2MP),以172.16.6.0/24为隧道网络,R3作为中心站点,通过NHRP协议实现分支站点(R5、R6、R7)的动态发现与注册。
2.OSPF多区域设计:
采用层次化设计,以MGRE隧道网络所在的区域为骨干区域 Area 0。
将其他网络划分为非骨干区域:172.16.33.0/24 网段为 Area 1,172.16.65.0/30 网段为 Area 2,172.16.97.0/30 网段为 Area 3,172.16.129.0/30 网段为 Area 4。
R3、R6、R7、R9作为ABR,连接多个区域,负责区域间路由的传递。
3.实现全网可达与外部路由引入:
在MGRE隧道接口上,将OSPF网络类型修改为broadcast,并配置DR优先级,确保邻居关系稳定。
在R12上运行RIP协议,并将其两个环回口的路由引入OSPF,使其成为ASBR(自治系统边界路由器),将外部路由通告到OSPF域内。
在R9上配置OSPF多进程(1和2),并通过import-route命令实现进程间的路由双向引入,打通Area 3与Area 4。
4.优化与安全策略:
减少LSA更新量:
在ABR(R3、R6、R7)上配置区域间路由聚合,将多个子网汇总为一条路由,减少Type-3 LSA的数量。
在ASBR(R12、R9)上配置外部路由聚合,减少Type-5 LSA的数量。
加快收敛:
修改OSPF接口的Hello和Dead计时器,使邻居状态变化能被更快地检测到,从而加速路由收敛。
保障更新安全:
在所有OSPF区域的接口上配置MD5认证,确保只有经过认证的设备才能交换路由信息,防止非法设备接入和路由欺骗。
5.实现公网访问:
在R3、R5、R6、R7上配置NAT,将内部私网地址转换为各自的公网接口地址,使得所有内网设备都能通过R4访问其环回口。
四、实验步骤
配置IP地址
R1]int g 0/0/0
[R1-GigabitEthernet0/0/0]ip a 172.16.33.1 24
[R1-GigabitEthernet0/0/0]int l0
[R1-LoopBack0]ip a 172.16.34.1 24
[R2]int g 0/0/0
[R2-GigabitEthernet0/0/0]ip a 172.16.33.2 24
[R2-GigabitEthernet0/0/0]int l0
[R2-LoopBack0]ip a 172.16.35.2 24
[R3]int g 0/0/0
[R3-GigabitEthernet0/0/0]ip a 172.16.33.3 24
[R3-GigabitEthernet0/0/0]int l0
[R3-LoopBack0]ip a 172.16.36.3 24
[R3-LoopBack0]int s 4/0/0
[R3-Serial4/0/0]ip a 34.0.0.3 24
[R4-ISP]int g 0/0/0
[R4-ISP-GigabitEthernet0/0/0]ip a 47.0.0.4 24
[R4-ISP-GigabitEthernet0/0/0]int l0
[R4-ISP-LoopBack0]ip a 172.16.2.4 24
[R4-ISP-LoopBack0]int s 3/0/0
[R4-ISP-Serial3/0/0]ip a 46.0.0.4 24
[R4-ISP-Serial3/0/0]int s 4/0/0
[R4-ISP-Serial4/0/0]ip a 34.0.0.4 24
[R4-ISP-Serial4/0/0]int s 4/0/1
[R4-ISP-Serial4/0/1]ip a 45.0.0.4 24
[R5]int l0
[R5-LoopBack0]ip a 172.16.3.5 24
[R5-LoopBack0]int s 4/0/0
[R5-Serial4/0/0]ip a 45.0.0.5 24
[R6]int g 0/0/0
[R6-GigabitEthernet0/0/0]ip a 172.16.65.1 30
[R6-GigabitEthernet0/0/0]int l0
[R6-LoopBack0]ip a 172.16.4.6 24
[R6-LoopBack0]int s 4/0/0
[R6-Serial4/0/0]ip a 46.0.0.6 24
[R7]int g 0/0/0
[R7-GigabitEthernet0/0/0]ip a 47.0.0.7 24
[R7-GigabitEthernet0/0/0]int g 0/0/1
[R7-GigabitEthernet0/0/1]ip a 172.16.97.1 30
[R7-GigabitEthernet0/0/1]int l0
[R7-LoopBack0]ip a 172.16.5.7 24
[R8]int g 0/0/0
[R8-GigabitEthernet0/0/0]ip a 172.16.97.2 30
[R8-GigabitEthernet0/0/0]int g 0/0/1
[R8-GigabitEthernet0/0/1]ip a 172.16.97.5 30
[R8-GigabitEthernet0/0/1]int l0
[R8-LoopBack0]ip a 172.16.98.8 24
[R9]int g0/0/0
[R9-GigabitEthernet0/0/0]ip a 172.16.97.6 30
[R9-GigabitEthernet0/0/0]int g 0/0/1
[R9-GigabitEthernet0/0/1]ip a 172.16.129.1 30
[R9-GigabitEthernet0/0/1]int l0
[R9-LoopBack0]ip a 172.16.130.9 24
[R10]int g 0/0/0
[R10-GigabitEthernet0/0/0]ip a 172.16.129.2 30
[R10-GigabitEthernet0/0/2]int l0
[R10-LoopBack0]ip a 172.16.131.10 24
[R11]int g 0/0/0
[R11-GigabitEthernet0/0/0]ip a 172.16.65.2 30
[R11-GigabitEthernet0/0/0]int g 0/0/1
[R11-GigabitEthernet0/0/1]ip a 172.16.65.5 30
[R11-GigabitEthernet0/0/1]int l0
[R11-LoopBack0]ip a 172.16.66.11 24
[R12]int g 0/0/0
[R12-GigabitEthernet0/0/0]ip a 172.16.65.6 30
[R12-GigabitEthernet0/0/0]int l0
[R12-LoopBack0]ip a 172.16.160.12 24
[R12-LoopBack0]int l1
[R12-LoopBack1]ip a 172.16.161.12 24
配置静态,是公网通
[R3]ip route-static 0.0.0.0 0 34.0.0.4
[R5]ip route-static 0.0.0.0 0 45.0.0.4
[R6]ip route-static 0.0.0.0 0 46.0.0.4
[R7]ip route-static 0.0.0.0 0 47.0.0.4
测试:
配置各个内网通
[R1]ospf 1 router-id 1.1.1.1
[R1-ospf-1]a 1
[R1-ospf-1-area-0.0.0.1]undo network 172.16.33.1 0.0.0.0
[R1-ospf-1-area-0.0.0.1]undo network 172.16.34.1 0.0.0.0
[R1-ospf-1-area-0.0.0.1]network 172.16.33.0 0.0.0.255
[R1-ospf-1-area-0.0.0.1]network 172.16.34.0 0.0.0.255
[R2]ospf 1 router-id 2.2.2.2
[R2-ospf-1]a 1
[R2-ospf-1-area-0.0.0.1]net 172.16.33.0 0.0.0.255
[R2-ospf-1-area-0.0.0.1]net 172.16.35.0 0.0.0.255
[R3]ospf 1 router-id 3.3.3.3
[R3-ospf-1]a 1
[R3-ospf-1-area-0.0.0.1]net 172.16.33.0 0.0.0.255
[R3-ospf-1-area-0.0.0.1]net 172.16.36.0 0.0.0.255
[R3-ospf-1]a 0
[R3-ospf-1-area-0.0.0.0]net 172.16.6.0 0.0.0.255
[R5]ospf 1 router-id 5.5.5.5
[R5-ospf-1]a 0
[R5-ospf-1-area-0.0.0.0]net 172.16.3.0 0.0.0.255
[R5-ospf-1-area-0.0.0.0]net 172.16.6.0 0.0.0.255
[R6]ospf 1 router-id 6.6.6.6
[R6]ospf 1
[R6-ospf-1]a 0
[R6-ospf-1-area-0.0.0.0]undo network 172.16.6.0 0.0.0.0
[R6-ospf-1-area-0.0.0.0]network 172.16.6.0 0.0.0.255
[R6-ospf-1]a 2
[R6-ospf-1-area-0.0.0.2]undo network 172.16.65.1 0.0.0.0
[R6-ospf-1-area-0.0.0.2]network 172.16.65.0 0.0.0.3
[R7]ospf 1 router-id 7.7.7.7
[R7-ospf-1]a 0
[R7-ospf-1-area-0.0.0.0]net 172.16.5.0 0.0.0.255
[R7-ospf-1-area-0.0.0.0]net 172.16.6.0 0.0.0.255
[R7-ospf-1]a 3
[R7-ospf-1-area-0.0.0.3]net 172.16.97.1 0.0.0.0
[R8]ospf 1 router-id 8.8.8.8
[R8-ospf-1]a 3
[R8-ospf-1-area-0.0.0.3]net 0.0.0.0 255.255.255.255
[R9]ospf 1 router-id 9.9.9.9
[R9-ospf-1]a 3
[R9-ospf-1-area-0.0.0.3]net 172.16.97.6 0.0.0.0
[R9]ospf 2
[R9-ospf-2]a 4
[R9-ospf-2-area-0.0.0.4]net 172.16.130.0 0.0.0.255
[R9-ospf-2-area-0.0.0.4]net 172.16.129.1 0.0.0.0
[R9]ospf 1
[R9-ospf-1]import-route ospf 2
[R9-ospf-1]q
[R9]ospf 2
[R9-ospf-2]import-route ospf 1
[R10]ospf 1 router-id 10.10.10.10
[R10-ospf-1]a 4
[R10-ospf-1-area-0.0.0.4]net 0.0.0.0 255.255.255.255
[R11]ospf 1 router-id 11.11.11.11
[R11]ospf 1
[R11-ospf-1]a 2
[R11-ospf-1-area-0.0.0.2]undo network 172.16.65.2 0.0.0.0
[R11-ospf-1-area-0.0.0.2]undo network 172.16.65.5 0.0.0.0
[R11-ospf-1-area-0.0.0.2]network 172.16.65.0 0.0.0.3
[R11-ospf-1-area-0.0.0.2]network 172.16.66.11 0.0.0.0
[R12]ospf 1 router-id 12.12.12.12
[R12-ospf-1]a 2
[R12-ospf-1-area-0.0.0.2]net 172.16.65.6 0.0.0.0
[R12]rip 1
[R12-rip-1]v 2
[R12-rip-1]undo s
[R12-rip-1]undo silent-interface
[R12-rip-1]undo summary
[R12-rip-1]net 172.16.0.0
[R12-ospf-1]import-route rip 1
配置MGRE VPN
[R3]int t 0/0/0
[R3-Tunnel0/0/0]ip a 172.16.6.3 24
[R3-Tunnel0/0/0]tunnel-protocol gre p2mp
[R3-Tunnel0/0/0]source 34.0.0.3
[R3-Tunnel0/0/0]nhrp network-id 1000
[R3-Tunnel0/0/0]nhrp entry multicast dynamic
[R3-Tunnel0/0/0]ospf network-type broadcast
[R5]int t 0/0/0
[R5-Tunnel0/0/0]ip a 172.16.6.5 24
[R5-Tunnel0/0/0]tunnel-protocol gre p2mp
[R5-Tunnel0/0/0]source Serial s4/0/0
Aug 2 2025 18:52:59-08:00 R5 %%01IFNET/4/LINK_STATE(l)[0]:The line protocol IP
on the interface Tunnel0/0/0 has entered the UP state.
[R5-Tunnel0/0/0]nhrp network-id 1000
[R5-Tunnel0/0/0]nhrp entry 172.16.6.3 34.0.0.3 register
[R5-Tunnel0/0/0]ospf network-type broadcast
[R5-Tunnel0/0/0]ospf dr-priority 0
[R6]int t 0/0/0
[R6-Tunnel0/0/0]ip a 172.16.6.6 24
[R6-Tunnel0/0/0]tunnel-protocol gre p2mp
[R6-Tunnel0/0/0]source s4/0/0
Aug 2 2025 18:54:14-08:00 R6 %%01IFNET/4/LINK_STATE(l)[0]:The line protocol IP
on the interface Tunnel0/0/0 has entered the UP state.
[R6-Tunnel0/0/0]nhrp network-id 1000
[R6-Tunnel0/0/0]nhrp entry 172.16.6.3 34.0.0.3 register
[R6-Tunnel0/0/0]ospf network-type broadcast
[R6-Tunnel0/0/0]ospf dr-priority 0
[R7]int t 0/0/0
[R7-Tunnel0/0/0]ip a 172.16.6.7 24
[R7-Tunnel0/0/0]tunnel-protocol gre p2mp
[R7-Tunnel0/0/0]source g0/0/0
Aug 2 2025 18:57:27-08:00 R7 %%01IFNET/4/LINK_STATE(l)[0]:The line protocol IP
on the interface Tunnel0/0/0 has entered the UP state.
[R7-Tunnel0/0/0]nhrp network-id 1000
[R7-Tunnel0/0/0][R6-Tunnel0/0/0]nhrp entry 172.16.6.3 34.0.0.3 register
[R7-Tunnel0/0/0]nhrp entry 172.16.6.3 34.0.0.3 register
[R7-Tunnel0/0/0]ospf network-type broadcast
[R7-Tunnel0/0/0]ospf dr-priority 0
测试:
配置NAT
[R3]acl 2000
[R3-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[R3]int s 4/0/0
[R3-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]int s 4/0/0
[R5-Serial4/0/0]nat outbound 2000
[R6]acl 2000
[R6-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[R6]int s 4/0/0
[R6-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]int g 0/0/0
[R7-GigabitEthernet0/0/0]nat outbound 2000
区域间的路由聚合,防环--精简area 0的LSDB、路由表
[R3]osp
[R3]ospf 1
[R3-ospf-1]a 1
[R3-ospf-1-area-0.0.0.1]ab
[R3-ospf-1-area-0.0.0.1]abr-summary 172.16.32.0 255.255.224.0
[R3]ip route-static 172.16.32.0 19 NULL 0
[R6]ospf 1
[R6-ospf-1]a 2
[R6-ospf-1-area-0.0.0.2]abr-summary 172.16.64.0 255.255.224.0
[R6]ip route-static 172.16.64.0 19 NULL 0
[R7]ospf 1
[R7-ospf-1]a 3
[R7-ospf-1-area-0.0.0.3]abr-summary 172.16.96.0 255.255.224.0
[R7]ip route-static 172.16.96.0 19 NULL 0
域外路由聚合,防环--精简area 0的LSDB、路由表
[R12]ospf 1
[R12-ospf-1]asbr-summary 172.16.160.0 255.255.224.0
[R12]ip route-static 172.16.160.0 19 NULL 0
[R9]ospf 1
[R9-ospf-1]asbr-summary 172.16.128.0 255.255.224.0
[R9]ip route-static 172.16.128.0 19 NULL 0
做特殊区域,精简除了AREA 0外的其他ospf区域的LSDB\路由表
[R1]ospf 1
[R1-ospf-1]a 1
[R1-ospf-1-area-0.0.0.1]stub no-summary
[R2]ospf 1
[R2-ospf-1]a 1
[R2-ospf-1-area-0.0.0.1]stub no-summary
[R6]ospf 1
[R6-ospf-1]a 2
[R6-ospf-1-area-0.0.0.2]nssa no-summary
[R7]ospf 1
[R7-ospf-1]a 3
[R7-ospf-1-area-0.0.0.3]nssa no-summary
[R8]ospf 1
[R8-ospf-1]a 3
[R8-ospf-1-area-0.0.0.3]nssa no-summary
[R9]ospf 1
[R9-ospf-1]a 3
[R9-ospf-1-area-0.0.0.3]nssa no-summary
[R10] ip route-static 0.0.0.0 0 172.16.129.1
测试:
加快收敛---更改HELLO时间
其他四个区域同理
区域认证、接口
测试