汇总路由回馈问题：完美解决 route-map + prefix-list

单点双向重发布：考虑汇总路由回馈问题

R1--OSPF--R2--EIGRP--R3
----->
<-----

R2#sh run
!
router eigrp 90
redistribute ospf 110 metric 10000 255 100 1 1500
network 23.1.1.2 0.0.0.0
no auto-summary
!
router ospf 110
router-id 2.2.2.2
log-adjacency-changes
summary-address 172.16.0.0 255.255.252.0
redistribute eigrp 90 subnets
network 12.1.1.2 0.0.0.0 area 0
!

R2:

172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
D 172.16.0.0/24 [90/2297856] via 23.1.1.3, 00:04:00, Serial1/1
O 172.16.0.0/22 is a summary, 00:00:20, Null0
D 172.16.1.0/24 [90/2297856] via 23.1.1.3, 00:04:30, Serial1/1
D 172.16.2.0/24 [90/2297856] via 23.1.1.3, 00:04:21, Serial1/1
D 172.16.3.0/24 [90/2297856] via 23.1.1.3, 00:04:11, Serial1/1


R3:

172.16.0.0/16 is variably subnetted, 5 subnets, 2 masks
C 172.16.0.0/24 is directly connected, Loopback4
D EX 172.16.0.0/22 [170/3137280] via 23.1.1.2, 00:00:22, Serial1/0
C 172.16.1.0/24 is directly connected, Loopback1
C 172.16.2.0/24 is directly connected, Loopback2
C 172.16.3.0/24 is directly connected, Loopback3

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防止汇总路由回馈：完美解决 route-map + prefix-list


R2#sh run b r e
router eigrp 90
redistribute ospf 110 metric 1000 255 100 1 1500 route-map anti-sum
network 23.1.1.2 0.0.0.0
no auto-summary
!
!
ip prefix-list anti-sum seq 5 permit 172.16.0.0/22
!
route-map anti-sum deny 10
match ip address prefix-list anti-sum
!
route-map anti-sum permit 20
!


R3：

172.16.0.0/24 is subnetted, 4 subnets
C 172.16.0.0 is directly connected, Loopback4
C 172.16.1.0 is directly connected, Loopback1
C 172.16.2.0 is directly connected, Loopback2
C 172.16.3.0 is directly connected, Loopback3