开头

OSPF是个链路状态路由协议

通过 交互链路状态 学习路由表
DR和BDR选举方法
自动选举DR和BDR
网段上routerID最大的路由器将被选举为DR,第二大的将被选举为BDR
实际上DR和BDR根据启动时间顺序选择
手工选择DR和BDR
优先级范围是0~255,数值越大,优先级越高,默认为1
如果优先级相同,则需要比较ROUTER ID
如果路由器的优先级被设置为0,它将不参与DR和DBR的选举
路由器的优先级可以影响一个选择过程,但是它不能强制更换已经存在的DR或DBDR路由器

实验拓扑:

OSPF实验(一)_链路

地址规划

IOU1

lo 0 1.1.1.1/32

e0/0 10.0.10.1/24

e0/1 10.0.13.1/24

IOU2

lo 0 2.2.2.2/32

e0/0 10.0.10.2/24

e0/1 10.0.11.1/24

IOU3

lo 0 3.3.3.3/32

e0/0 10.0.11.2/24

e0/1 10.0.12.1/24

IOU4

lo 0 4.4.4.4/32

e0/0 10.0.12.2/24

e0/1 10.0.13.2/24

IOU1的配置

Configure terminal

Interface loopback 0

Ip address 1.1.1.1 255.255.255.255

No shutdown

Exit

Interface Ethernet 0/0

Duplex full

Ip address 10.0.10.1 255.255.255.0

No shutdown

Exit

Interface Ethernet 0/1

Duplex full

Ip address 10.0.13.1 255.255.255.0

No shutdown

Exit

Router ospf 1

Router-id 1.1.1.1

Network 10.0.10.0 0.0.0.255 area 0

Network 10.0.13.0 0.0.0.255 area 0

Network 1.1.1.1 0.0.0.0 area 0

exit

IOU2的配置

Configure terminal

Interface loopback 0

Ip address 2.2.2.2 255.255.255.255

No shutdown

Exit

Interface Ethernet 0/0

Duplex full

Ip address 10.0.10.2 255.255.255.0

No shutdown

Exit

Interface Ethernet 0/1

Duplex full

Ip address 10.0.11.1 255.255.255.0

No shutdown

Exit

Router ospf 1

Router-id 2.2.2.2

Network 10.0.10.0 0.0.0.255 area 0

Network 10.0.11.0 0.0.0.255 area 0

Network 2.2.2.2 0.0.0.0 area 0

exit

IOU3的配置

Configure terminal

Interface loopback 0

Ip address 3.3.3.3 255.255.255.255

No shutdown

Exit

Interface Ethernet 0/0

Duplex full

Ip address 10.0.11.2 255.255.255.0

No shutdown

Exit

Interface Ethernet 0/1

Duplex full

Ip address 10.0.12.1 255.255.255.0

No shutdown

Exit

Router ospf 3

Router-id 3.3.3.3

Network 10.0.12.0 0.0.0.255 area 0

Network 10.0.11.0 0.0.0.255 area 0

Network 3.3.3.3 0.0.0.0 area 0

exit

IOU4的配置

Configure terminal

Interface loopback 0

Ip address 4.4.4.4 255.255.255.255

No shutdown

Exit

Interface Ethernet 0/0

Duplex full

Ip address 10.0.12.2 255.255.255.0

No shutdown

Exit

Interface Ethernet 0/1

Duplex full

Ip address 10.0.13.2 255.255.255.0

No shutdown

Exit

Router ospf 1

Router-id 4.4.4.4

Network 10.0.12.0 0.0.0.255 area 0

Network 10.0.13.0 0.0.0.255 area 0

Network 4.4.4.4 0.0.0.0 area 0

exit

使用show命令查看配置是否正确

show IP route

OSPF实验(一)_优先级_02

show IP ospf neighbor

OSPF实验(一)_链路_03