3Com Router User Manual

Configuring IP Routing Policy487
Ta b l e 567   Display and Debug of IP Routing Policy
Configuring IP 
Routing PolicyThis example explains how an OSPF protocol selectively imports an RIP route.
As shown in the following figure, the router connects a campus network which 
uses RIP as its internal routing protocol and an external area network which uses 
OSPF routing protocol. The router advertises some routing information of the 
campus network around the external area network. To implement this, the OSPF...

488CHAPTER 31: CONFIGURING IP ROUTING POLICY
Figure 158   Networking diagram of configuring OSPF route filtering
1Configure Router A:
aConfigure static routes:
[RouterA]ip route-static 20.0.0.1 32 ethernet 0 
[RouterA]ip route-static 30.0.0.1 32 ethernet 0 
[RouterA]ip route-static 40.0.0.1 32 ethernet 0 
bStart OSPF protocol.
[RouterA]router id 1.1.1.1 
[RouterA]ospf enable 
cImport static route
[RouterA-ospf]import-route static 
dConfigure Serial 0, and specify id of area including the interface....

Troubleshooting IP Routing Policy489
Figure 159   Networking diagram of filtering the distributed routing information
1Configure ip-prefix
[Router]ip ip-prefix p1 permit 192.1.1.0/24 
2Configure RIP protocol 
[Router]rip 
[Router-rip]network 192.1.0.0 
[Router-rip]network 202.1.1.0 
[Router-rip]filter-policy ip-prefix p1 export 
Troubleshooting IP 
Routing PolicyRouting information cannot be filtered when the routing protocol is in 
normal operation
Check the following:
■At least one node in the routing...

490CHAPTER 31: CONFIGURING IP ROUTING POLICY 

32
CONFIGURING IP POLICY ROUTING
This chapter covers the following topics:
■IP Policy Routing Overview
■Configuring IP Policy Routing
■Displaying and Debugging IP Policy Routing
■IP Policy Routing Configuration Example
IP Policy Routing 
OverviewIP policy routing is a mechanism in which messages are transmitted and forwarded 
by strategy without going through the routing table. When a router is forwarding 
a packet by policy routing, it is first filtered by a route policy which decides the 
packets to be...

492CHAPTER 32: CONFIGURING IP POLICY ROUTING
Creating a Routing 
PolicyThe strategy specified with the strategy name may have several strategy points 
and each strategy point is specified with sequence-num. The smaller the 
sequence-num, the higher the preference and the defined strategy will be 
executed first. This strategy can be used to import routes and perform policy 
routing when IP messages are forwarded. When a routing policy is recreated, the 
configuration information of the new routing policy...

Displaying and Debugging IP Policy Routing493
You can specify multiple next-hops or send the message to multiple interfaces. 
Generally, only the first parameter works. If the first parameter is mismatched, the 
second parameter will take effect, and so on.
By default, no apply clause is defined.
Enabling and Disabling 
Local Policy RoutingPerform the following configurations in system view.
Ta b l e 571   Enable/Disable the Local Policy Routing
By default, local policy routing is disabled. Only one...

494CHAPTER 32: CONFIGURING IP POLICY ROUTING
IP Policy Routing 
Configuration 
ExampleThis section describes two different configurations for IP policy routing with a 
suggested procedure for each configuration.
Configure Policy Routing 
Based on Source AddressDefine a policy named “aaa” that includes two nodes, through which all TCP 
messages are transferred from serial interface 0 and the others are transferred 
from serial interface 1.
■Node 10 indicates that messages matched with access list 102 will...

IP Policy Routing Configuration Example495
4Adopt policy aaa in Ethernet interface 
[Router-route-policy]interface ethernet 0 
[Router-Ethernet0]ip policy route-policy aaa 
Configure Policy Routing 
Based on Message SizeRouter A sends the messages of 64-100 bytes through S0, messages of 101-1000 
bytes through S1 and those of other sizes must be routed normally.
Apply IP policy routing lab1 on E0 of Router A. This strategy sets message of 
64-100 bytes to 150.1.1.2 as the IP address of next forwarding...

496CHAPTER 32: CONFIGURING IP POLICY ROUTING
[RouterA]debugging ip policy-routing
IP:  s=151.1.1.1(local),d=152.1.1.1, len  64, policy match
IP:  route map lab1, item 10, permit
IP:  s=151.1.1.1(local),d=152.1.1.1, len  64, policy routed
IP:  local to serial 150.1.1.2
On Router A, change the message size to 101 bytes and monitor policy routing 
with debug ip policy command. Note: the messages of 101 bytes match the entry 
item whose serial number 20 as shown in the routing diagram lab1. They are sent 
to...