Motorola BSR 2000, Руководство по настройке и управлению

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Release 1.0 Configuring BGP
526360-001-00 Rev. B MGBI 12-49
Configuring the Community Attribute
A community is a group of destinations that share a common policy. You can define
the communities a destination belongs to. This determines how routes are advertised.
Use a route map to set the community attribute. BGP defines the following
well-known communities:
■
no-export
advertises a route to IBGP peers only (peers within the local AS).
■
no advertise
does not advertise a route to any peer.
■
local
advertises a route only to peers in the same subconfederation.
Examples
The following example sets the value of the community attribute:
MOT(config)#route map 20 permit 10
MOT(config-bgp)#match ip address 2
MOT(config-bgp)#set community no-advertise
MOT(config-bgp)#exit
MOT(config)#route-map 20 permit 20
MOT(config-bgp)#match as-path 2
MOT(config-bgp)#set community 300 additive
MOT(config-bgp)#exit
The following example uses the send community command to send the community
attribute to a neighbor:
MOT(config)#router bgp 100
MOT(config-bgp)#neighbor 5.5.5.5 remote-as 400
MOT(config-bgp)#neighbor 5.5.5.5 send-community
MOT(config-bgp)#neighbor 5.5.5.5 route-map 20 out
MOT(config-bgp)#exit
Configuring Routing Policy
Route maps define the conditions for redistributing routes from one routing protocol
to another (for example, between BGP and OSPF) and for advertising and learning
routes from one router to another. A route map consists of a set of
route-map
commands, match statements defining conditions that a route must meet and set
statements defining the conditions that apply to a route.
To define a route map, use the route-map command in Global Configuration mode:
MOT(config)#
route-map <
WORD
> [ permit | deny ] <
0-65535
>
where: