Configuring A Community List; Applying A Routing Policy To Import Routes - H3C S7500 Series Operation Manual

Operation Manual – Routing Protocol
H3C S7500 Series Ethernet Switches
By default, no AS path list is defined.

7.2.4 Configuring a Community List

In BGP, community attributes are optional transit attributes. Some community
attributes are globally recognized and they are called standard community attributes.
Some are for special purposes and they can be customized.
A route can have one or more community attributes. The speaker of multiple
community attributes of a route can act based on one, multiple or all attributes. A
router can decide whether to change community attributes before forwarding a route
to peers.
A community list is used to identify community information. It falls in to two types:
basic community list and advanced community list. The former ranges from 1 to 99,
and the latter ranges from 100 to 199.
Follow these steps to configure a community list:
To do...
Enter system view
Configure a basic
community list
Configure an
advanced
community list
By default, no BGP community list is defined.

7.2.5 Applying a Routing Policy to Import Routes

A routing protocol can import the routes discovered by other routing protocols to
enrich its route knowledge. During route import, you can adopt a route-policy to filter
routing information, so as to import only needed routes. If the destination routing
protocol cannot directly use the cost of the source routing protocol, you should specify
a cost for the imported routes.
Note:
The import-route command (used to import routes) is somewhat different in form in
different routing protocol views. Refer to the import-route command description
under routing protocols in the command manual.
Use the command...
system-view
ip community-list
basic-comm-list-number { permit | deny }
[ aa:nn | internet | no-export-subconfed |
no-advertise | no-export ]*
ip community-list adv-comm-list-number
{ permit | deny } comm-regular-expression
7-8
Chapter 7 IP Routing Policy Configuration
Remarks
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Optional
Optional