beautypg.com

2 ip routing policy, 1 introduction to routing policy, Outing – Accton Technology ES4626 User Manual

Page 361: Olicy

background image

361

Static route

1

RIP 120

OSPF ASE

150

IBGP 200

EBGP 20

Unknown route

255

13.2 IP Routing Policy

13.2.1 Introduction To Routing Policy

Some policies have to be applied when the router publishing and receiving routing

messages so to filter routing messages, such as only receiving or publishing routing

messages meets the specified conditions. A routing protocol maybe need redistribute

other routing messages found by other protocols such as OSPF so to increase its own

routing knowledge; when the router redistributing routing messages from other routing

protocols there may be only part of the qualified routing messages is needed, and some

properties may have to be configured to suit this protocol.

To achieve routing policy, first we have to define the characteristics of the routing

messages to be applied with routing policies, namely define a group matching rules. We

can configure by different properties in the routing messages such as destination address,

the router address publishing the routing messages. The matching rules can be

previously configured to be applied in the routing publishing, receiving and distributing

policies.

Five filters are provided in ES4624-SFP/ES4626-SFP switch: route-map, acl,

as-path, community-list and ip-prefix for use. We will introduce each filter in following

sections:

1. route-map

For matching certain properties of the specified routing information and setting some

routing propertities when the conditions are fulfilled.

Route-map is for controlling and changing the routing messages while also

controlling the redistribution among routes. A route-map consists of a series of match and

set commands in which the match command specifies the conditions required matching,

and the set command specifies the actions to be taken when matches. The route-map is

also for controlling route publishing among different route process. It can also used on

policy routing which select different routes for the messages other than the shortest

route.

A group matches and set clauses make up a node. A route-map may consist of

This manual is related to the following products: