3Com Switch 8800 Configuration Guide
Chapter 22 IP Routing Policy Configuration
22-8
22.2.4 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.
Table 22-6
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
}
By default, a BGP community attribute list is not configured.
22.2.5 Importing Routing Information Discovered by Other Routing
Protocols
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.
Table 22-7
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
]
