Debugging policy-based routing

Debugging policy-based routing
Below is the configuration and output from an exchange between the routers LAB1 and
LAB2, regarding LAB3:
LAB1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
LAB1(config)#access-list 100 permit ip any 192.168.100.0 0.0.0.255
LAB1(config)#route-map Sendtot1 permit 10
LAB1(config-route-map)#match ip address 100
LAB1(config-route-map)#set interface s0
LAB1(config-route-map)#exit
LAB1(config)#interface s2
LAB1(config-if)#ip policy route-map Sendtot1
LAB1(config-if)#^Z
LAB1#debug ip policy
Policy routing debugging is on
192.168.100.0
192.168.31.0
192.168.12.0
Lab3
Lab1
Lab2
E0
.1
.1 .1
.1
192.168.13.0
S0
S0
S0
S2
S1
S1
.2
.2
T1 .2
336 Chapter 10  Route Optimization
LAB2#ping 192.168.100.1
LAB1#
8w4d: IP: s=192.168.12.2 (Serial2), d=192.168.100.1, len 100, policy match
8w4d: IP: route map SENDTOT1, item 10, permit
8w4d: IP: s=192.168.12.2 (Serial2), d=192.168.100.1 (Serial0), len 100,
➥policy routed
8w4d: IP: Serial2 to Serial0 192.168.100.1
LAB1#
LAB2#ping 10.0.0.1
LAB1#
8w4d: IP: s=192.168.12.2 (Serial2), d=10.0.0.1 (Serial0), len 100,
➥policy rejected -- normal forwarding
LAB1#
Notice how the 56K link on LAB1’s interface S1 is not used in this exchange. This policy may
have been necessary because a protocol such as RIP was load-balancing across the two links, as
if they were equal. The result of the PBR configuration is that traffic coming in LAB1’s S2 interface,
bound for the 192.168.100.0 network, is forced over the T1, making traffic flow much
faster overall.