一、R4为ISP,其上只能配置IP地址;R4与其他所有直连设备间均使用公有IP。
首先进行IP地址规划,一共六个区域,将172.16.0.0/16分为六个网段。
配置area 0公网
[r3-Serial4/0/0]ip address 34.0.0.1 24
[r5-Serial4/0/0]ip address 45.0.0.1 24
[r6-Serial4/0/0]ip address 46.0.0.1 24
[r7-GigabitEthernet0/0/0]ip address 47.0.0.1 24
[r4-LoopBack0]ip address 4.4.4.4 24
[r4-Serial4/0/0]ip address 34.0.0.2 24
[r4-Serial4/0/1]ip address 45.0.0.2 24
[r4-Serial3/0/0]ip address 46.0.0.2 24
[r4-GigabitEthernet0/0/0]ip address 47.0.0.2 24
二、R3、R5、R6、R7为MGRE环境,R3为中心站点。
[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
搭建MGRE环境
[r3-Tunnel0/0/0]ip address 172.16.0.129 29
[r3-Tunnel0/0/0]tunnel-protocol gre p2mp
[r3-Tunnel0/0/0]source 34.1.1.1
[r3-Tunnel0/0/0]nhrp entry multicast dynamic
[r3-Tunnel0/0/0]nhrp network-id 100
[r5-Tunnel0/0/0]ip address 172.16.0.130 29
[r5-Tunnel0/0/0]tunnel-protocol gre p2mp
[r5-Tunnel0/0/0]nhrp entry 172.16.0.129 34.1.1.1 register
[r5-Tunnel0/0/0]nhrp network-id 100
[r5-Tunnel0/0/0]source Serial 4/0/0
[r6-Tunnel0/0/0]ip address 172.16.0.131 29
[r6-Tunnel0/0/0]tunnel-protocol gre p2mp
[r6-Tunnel0/0/0]nhrp entry 172.16.0.129 34.1.1.1 register
[r6-Tunnel0/0/0]nhrp network-id 100
[r6-Tunnel0/0/0]source Serial 4/0/0
[r7-Tunnel0/0/0]ip address 172.16.0.132 29
[r7-Tunnel0/0/0]tunnel-protocol gre p2mp
[r7-Tunnel0/0/0]nhrp entry 172.16.0.129 34.1.1.1 register
[r7-Tunnel0/0/0]nhrp network-id 100
[r7-Tunnel0/0/0]source GigabitEthernet 0/0/0
三、整个OSPF环境IP地址基于172.16.0.0/16划分。
#区域0
[r5-LoopBack0]ip adress 172.16.1.1 25
[r6-LoopBack0]ip adress 172.16.1.129 25
[r7-LoopBack0]ip adress 172.16.2.1 25
#区域1
[r1-LoopBack0]ip adress 172.16.33.1 25
[r1-GigabitEthernet0/0/0]ip adress 172.16.32.129 29
[r2-LoopBack0]ip adress 172.16.33.129 25
[r2-GigabitEthernet0/0/0]ip ad 172.16.32.130 29
[r3-LoopBack0]ip adress 172.16.34.1 25
[r3-GigabitEthernet0/0/0]ip ad 172.16.32.131 29
#区域2
[r6-GigabitEthernet0/0/0]ip adress 172.16.64.1 30
[r11-LoopBack0]ip adress 172.16.65.1 25
[r11-GigabitEthernet0/0/0]ip adress 172.16.64.2 30
[r11-GigabitEthernet0/0/1]ip adress 172.16.64.5 30
[r12-LoopBack0]ip adress 172.16.160.1 20
[r12-LoopBack1]ip adress 172.16.176.1 20
[r12-GigabitEthernet0/0/0]ip adress 172.16.64.6 30
#区域3
[r7-GigabitEthernet0/0/1]ip adress 172.16.96.1 30
[r8-LoopBack0]ip address 172.16.97.1 25
[r8-GigabitEthernet0/0/0]ip adress 172.16.96.2 30
[r8-GigabitEthernet0/0/1]ip adress 172.16.96.5 30
[r9-LoopBack0]ip adress 172.16.129.1 25
[r9-GigabitEthernet0/0/0]ip adress 172.16.96.6 30
[r9-GigabitEthernet0/0/1]ip adress 172.16.128.1 30
#区域4
[r10-LoopBack0]ip adress 172.16.129.129 25
[r10-GigabitEthernet0/0/0]ip adress 172.16.128.2 30
配置ospf [r1]直[r12]按照各自的网段配置
[r1]ospf 1 router-id 1.1.1.1
[r1-ospf-1]area 1
[r1-ospf-1-area-0.0.0.1]network 172.16.0.0 0.0.255.255
[r2]
........
[r12]
四、所有设备均可访问R4的环回
查看邻居
[r3-Tunnel0/0/0]ospf network-type broadcast
[r5-Tunnel0/0/0]ospf network-type broadcast
[r5-Tunnel0/0/0]ospf dr-priority 0
[r6-Tunnel0/0/0]ospf network-type broadcast
[r6-Tunnel0/0/0]ospf dr-priority 0
[r7-Tunnel0/0/0]ospf network-type broadcast
[r7-Tunnel0/0/0]ospf dr-priority 0
设置特殊区域并配置空接口
[r1]ospf 1
[r1-ospf-1]area 1
[r1-ospf-1-area-0.0.0.1]stub
[r2]ospf 1
[r2-ospf-1]area 1
[r2-ospf-1-area-0.0.0.1]stub
[r3]ospf 1
[r3-ospf-1]area 1
[r3-ospf-1-area-0.0.0.1]stub-summary
[r3]ip route-static 172.16.32.0 19 NULL 0
[r6]ospf 1
[r6-ospf-1]area 2
[r6-ospf-1-area-0.0.0.2]nssa no-summary
[r6]ip route-static 172.16.64.0 19 NULL 0
[r7]ospf 1
[r7-ospf-1]area 3
[r7-ospf-1-area-0.0.0.3]nssa no-summary
[r7]ip route-static 172.16.96.0 19 NULL 0
[r9]ospf 1
[r9-ospf-1]area 3
[r9-ospf-1-area-0.0.0.3]nssa
[r9]ip route-static 172.16.128.0 19 NULL 0
[r11]ospf 1
[r11-ospf-1]area 2
[r11-ospf-1-area-0.0.0.2]nssa
[r12]ospf 1
[r12-ospf-1]area 2
[r12-ospf-1-area-0.0.0.2]nssa
[r12]ip route-static 172.16.160.0 19 NULL 0
五、减少LSA的更新量,加快收敛,保证更新安全。
[r3]ospf 1
[r3-ospf-1]area 1
[r3-ospf-1-area-0.0.0.1]abr-summary 172.16.32.0 255.255.224.0
[r6]ospf 1
[r6-ospf-1]area 2
[r6-ospf-1-area-0.0.0.2]abr-summary 172.16.64.0 255.255.224.0
[r7]ospf 1
[r7-ospf-1]area 3
[r7-ospf-1-area-0.0.0.3]abr-summary 172.16.96.0 255.255.224.0
[r9]ospf 1
[r9-ospf-1]asbr-summary 172.16.128.0 255.255.224.0
[r12]ospf 1
[r12-ospf-1]asbr-summary 172.16.160.0 255.255.224.0
设置NAT
[r3]acl 2000
[r3-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[r3]int g0/0/0
[r3-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]int g0/0/0
[r6-GigabitEthernet0/0/0]nat outbound 2000
[r7]acl 2000
[r7-acl-basic-2000]rule permit source 172.16.0.0 0.0.255.255
[r7]int g0/0/1
[r7-GigabitEthernet0/0/1]nat outbound 2000
加快收敛
AR3
[r3]int t0/0/0
[r3-Tunnel0/0/0]ospf timer hello 10
AR5
[r5]int t0/0/0
[r5-Tunnel0/0/0]ospf timer hello 10
AR6
[r6]int t0/0/0
[r6-Tunnel0/0/0]ospf timer hello 10
AR7
[r7]int t0/0/0
[r7-Tunnel0/0/0]ospf timer hello 10