Bgp speaker and bgp peer, Bgp message types, Configuring a large-scale bgp network – H3C Technologies H3C S12500-X Series Switches User Manual

Page 249: Configuring bgp community

Advertising
background image

235

76B

Configuring a large-scale BGP network

In a large network, the number of BGP connections is huge and BGP configuration and maintenance are
complicated. To simply BGP configuration, you can use the peer group, community, route reflector, and

confederation features as needed. For more information about configuring peer groups, see

"

1155H

Configuring a BGP peer group

."

336B

Configuring BGP community

By default, a router does not advertise the COMMUNITY or extended community attribute to its peers or

peer groups. When the router receives a route carrying the COMMUNITY or extended community
attribute, it removes the attribute before advertising the route to other peers or peer groups.
Perform this task to enable a router to advertise the COMMUNITY or extended community attribute to its

peers for route filtering and control. You can also reference a routing policy to add or modify the

COMMUNITY or extended community attribute for specific routes. For more information about routing
policy, see "

1156H

Configuring routing policies

."

To configure BGP community (IPv4):

Step Command

Remarks

1.

Enter system view.

system-view

N/A

2.

Enter BGP view or BGP-VPN
instance view.

Enter BGP view:

bgp as-number

Enter BGP-VPN instance view:

a.

bgp as-number

b.

ip vpn-instance

vpn-instance-name

N/A

3.

Enter BGP IPv4 unicast
address family view or

BGP-VPN IPv4 unicast

address family view.

address-family ipv4 [ unicast ]

N/A

4.

Advertise the COMMUNITY
or extended community

attribute to a peer or peer

group.

Advertise the COMMUNITY
attribute to a peer or peer

group:

peer { group-name |
ip-address
}

advertise-community

Advertise the extended

community attribute to a peer

or peer group:

peer { group-name |
ip-address
}

advertise-ext-community

By default, the COMMUNITY or
extended community attribute is

not advertised.

5.

(Optional.) Apply a routing
policy to routes advertised to

a peer or peer group.

peer { group-name | ip-address }
route-policy route-policy-name

export

By default, no routing policy is
applied.

To configure BGP community (IPv6):

Advertising
This manual is related to the following products: