Operation Manual – Routing ProtocolH3C S7500 Series Ethernet Switches Chapter 7 IP Routing Policy Configuration7-1Chapter 7 IP Routing Policy ConfigurationWhen configuring IP routing policies, go to these sections for information you areinterested in:z IP Routing Policy Overviewz IP Routing Policy Configurationz Displaying and Maintaining IP Routing Policy Configurationz IP Routing Policy Configuration Examplez Troubleshooting IP Routing Policy7.1 IP Routing Policy OverviewWhen a router advertises or receives routing information, it may need to implementsome policies to filter routing information in order to advertise or distribute only therouting information meeting the given conditions. A routing protocol (RIP, for example)may need to import the routing information discovered by other protocols like OSPF toenrich its routing knowledge. While importing routing information from other protocols,the router possibly only needs to import the routes meeting the given conditions andset some attributes of the imported routes to make them meet the requirements of thisprotocol.To implement a routing policy, you need to define a set of matching rules by specifyingthe characteristics of the routing information to be filtered. You can set the rules basedon such attributes as destination address and source address. The matching rulescan be set in advance and then used in routing policies to advertise, receive, or importroutes.7.1.1 FiltersThe S7500 series provide five kinds of filters (route-policy, ACL, AS-path,community-list and ip-prefix) for routing protocols reference. The following sectionsdescribe these filters.I. Route-policyA route-policy is used to match some attributes of route information and the attributesof route information will be set if the conditions are satisfied.A route policy comprises multiple nodes. Each node is a unit for matching test. Nodesare matched by their node numbers. Each node comprises a set of if-match andapply clauses. The if-match clauses define matching rules. Matching objects aresome attributes of routing information. The relationship among the if-match clausesfor a node is “AND”. As a result, a matching test against a node is successful only
