1、特殊区域totally stub解析区域类型作用默认路由备注命令stub过滤LSA4、LSA5ABR默认下发3类默认路由，seed cost值为1本区域所有路由器都必须配置成stub，否则邻居起不
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1、特殊区域totally stub解析
| 区域类型 | 作用 | 默认路由 | 备注 | 命令 |
| stub | 过滤LSA4、LSA5 | ABR默认下发3类默认路由，seed cost值为1 | 本区域所有路由器都必须配置成stub，否则邻居起不来，且不能包含ASBR | area 2 stub area 2 default-cost x |
| totally stub | 过滤LSA3、LSA4、LSA5 | ABR默认下发3类默认路由，seed cost值为1 | 本区域所有路由器都必须配置成stub，否则邻居起不来，且不能包含ASBR | area 2 stub no-summary |
2、实验拓扑
3、实验配置
R1配置
interface Loopback0
ip address 1.1.1.1 255.255.255.0
interface Serial0/0
ip address 12.1.1.1 255.255.255.0
router ospf 110
router-id 1.1.1.1
network 12.1.1.0 0.0.0.255 area 2
R2配置
interface Loopback0
ip address 2.2.2.2 255.255.255.0
interface Serial0/0
ip address 12.1.1.2 255.255.255.0
interface Serial0/1
ip address 23.1.1.2 255.255.255.0router ospf 110
router-id 2.2.2.2
network 12.1.1.0 0.0.0.255 area 2
network 23.1.1.0 0.0.0.255 area 0
R3配置
interface Loopback0
ip address 3.3.3.3 255.255.255.0
interface Serial0/0
ip address 34.1.1.3 255.255.255.0
interface Serial0/1
ip address 23.1.1.3 255.255.255.0router ospf 110
router-id 3.3.3.3
network 23.1.1.0 0.0.0.255 area 0
network 34.1.1.0 0.0.0.255 area 1
R4配置
interface Loopback0
ip address 4.4.4.4 255.255.255.0
interface Serial0/0
ip address 34.1.1.4 255.255.255.0
interface Serial0/1
ip address 45.1.1.4 255.255.255.0
router ospf 110
router-id 4.4.4.4
redistribute rip subnets
network 34.1.1.0 0.0.0.255 area 1
R5配置
interface Loopback0
ip address 5.5.5.5 255.255.255.0
interface Serial0/1
ip address 45.1.1.5 255.255.255.0
serial restart-delay 0
router rip
version 2
network 5.0.0.0
network 45.0.0.0
no auto-summary
4、实验验证
过滤LSA3、LSA4、LSA4
配置totally stub前
配置totally stub后
ABR下放3类默认路由
配置totally stub前
配置totally stub后
