3Com Switch 8800 Family Configuration Guide

Configuring IP Routing Policy 399
Configuring a
Community Attribute
List
In BGP, community attribute is optional and transitive. Some community attributes
known globally are called standard community attributes. Some community
attributes are for special purpose. You can also define expanded community
attribute.
A route can have one more community attributes. The speakers of multiple
community attributes of a route can act according to one, several or all attributes.
A router can select community attribute modification before transmitting routes to
other peers.
Community lists, which identify community information, can be divided into
basic-community-lists and advanced-community-lists. Basic-community-lists range
from 1 to 99, while advanced-community-lists range from 100 to 199.
Perform the following configuration in system view.
By default, a BGP community attribute list is not configured.
Applying Route Policy
on Imported Routes
A routing protocol can import the routes discovered by other routing protocols to
enrich its route information. The route-policy can be used for route information
filtering to implement the purposeful redistribution. If the destination routing
protocol importing the routes cannot directly reference the route costs of the
source routing protocol, you should satisfy the requirement of the protocol by
specifying a route cost for the imported route.
Perform the following configuration in routing protocol view.
By default, the routes discovered by other protocols will not be advertised.
n
In different routing protocol views, the parameter options are different. For
details, respectively refer to the import-route command in different protocols.
Tab le 398 Configure a community attribute list
Operation Command
Configure a basic
community-list
ip community-list basic-comm-list-number { permit | deny } [
aa:nn ]* [ internet | no-export-subconfed | no-advertise |
no-export ]*
Configure an advanced
community-list
ip community-list adv-comm-list-number { permit | deny }
comm-regular-expression
Cancel a community-list
undo ip community-list { basic-comm-list-number |
adv-comm-list-number }
Tab le 399 Configure to import the routes of other protocols
Operation Command
Set to import routes of other
protocols
import-route protocol [ med med | cost cost ] [ tag value ] [
type 1 | 2 ] [ route-policy route-policy-name ]
Cancel the setting for
importing routes of other
protocols
undo import-route protocol