Chapter 7 Ip Routing Policy Configuration; Ip Routing Policy Overview - H3C S7500 Series Operation Manual

Operation Manual – Routing Protocol
H3C S7500 Series Ethernet Switches

Chapter 7 IP Routing Policy Configuration

When configuring IP routing policies, go to these sections for information you are
interested in:

IP Routing Policy Overview

IP Routing Policy Configuration
Displaying and Maintaining IP Routing Policy Configuration
IP Routing Policy Configuration Example
Troubleshooting IP Routing Policy
7.1 IP Routing Policy Overview
When a router advertises or receives routing information, it may need to implement
some policies to filter routing information in order to advertise or distribute only the
routing information meeting the given conditions. A routing protocol (RIP, for example)
may need to import the routing information discovered by other protocols like OSPF to
enrich its routing knowledge. While importing routing information from other protocols,
the router possibly only needs to import the routes meeting the given conditions and
set some attributes of the imported routes to make them meet the requirements of this
protocol.
To implement a routing policy, you need to define a set of matching rules by specifying
the characteristics of the routing information to be filtered. You can set the rules based
on such attributes as destination address and source address. The matching rules
can be set in advance and then used in routing policies to advertise, receive, or import
routes.
7.1.1 Filters
The S7500 series provide five kinds of filters (route-policy, ACL, AS-path,
community-list and ip-prefix) for routing protocols reference. The following sections
describe these filters.
I. Route-policy
A route-policy is used to match some attributes of route information and the attributes
of route information will be set if the conditions are satisfied.
A route policy comprises multiple nodes. Each node is a unit for matching test. Nodes
are matched by their node numbers. Each node comprises a set of if-match and
apply clauses. The if-match clauses define matching rules. Matching objects are
some attributes of routing information. The relationship among the if-match clauses
for a node is "AND". As a result, a matching test against a node is successful only
Chapter 7 IP Routing Policy Configuration
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