要求:但是从源IP:5.5.5.5/32出来的数据包必须走R4:并且保证链路的畅通性:
interface Loopback0
ip address
interface FastEthernet1/0
ip address 1.1.56.5 255.255.255.0
interface FastEthernet1/1
ip address 1.1.45.5 255.255.255.0
ip policy route-map AAA
ip local policy route-map AAA
ip route 0.0.0.0 0.0.0.0 1.1.56.6
route-map AAA permit 10
match interface Loopback0
set ip next-hop 1.1.45.4
R5#debug ip policy
R5#ping 4.4.4.4 sou lo0 :这里注意:如果是本地产生的流量,route-map默认是不匹配的,需要启用:[ip local policy route-map AAA]:才能让本地流量匹配AAA:
*Dec 3 18:48:32.823: IP: route map AAA, item 10, permit
*Dec 3 18:48:32.827: IP: s=5.5.5.5 (local), d=4.4.4.4 (FastEthernet1/1), len 100, policy routed
*Dec 3 18:48:32.827: IP: local to FastEthernet1/1 1.1.45.4
【不通】:解释:route-map无法区分下一跳是否可达。但是可以结合SLA来实现:
type echo protocol ipIcmpEcho
frequency 10
ip sla monitor schedule 1 life forever start-time now
track 2 rtr 1
route-map AAA permit 10
match interface Loopback0
set ip next-hop verify-availability 1.1.45.4 1 track 2
Wan30#debug ip policy
*Dec 3 18:49:42.115: IP: s=5.5.5.5 (local), d=4.4.4.4, len 100, policy match
*Dec 3 18:49:42.115: IP: route map AAA, item 10, permit
*Dec 3 18:49:42.115: IP: s=5.5.5.5 (local), d=4.4.4.4, len 100, policy rejected -- normal forwarding