221
SwitchB(config#router bgp 100
SwitchB(config-router-bgp)#aggregate 193.0.0.0/24
At the same time, the aggregation command above can be modified as following, then this
switch only announce aggregation route 193.0.0.0 and forbid to announce more specified route
to all the neighbors.
SwitchB(config-router-bgp)#aggregate 193.0.0.0/24 summary-only
1.8.4.3 Examples 3: configure BGP community attributes
In the following sample, “route map set-community” is used for the outgoing update to
neighbor 16.1.1.6. By accessing to route in table 1 to configure special community value to
“1111”, other can be announced normally.
Switch(config)#router bgp 100
Switch(config-router-bgp)#neighbor 16.1.1.6 remote-as 200
Switch(config-router-bgp)#neighbor 16.1.1.6 route-map set-community out
Switch(config-router-bgp)#exit
Switch(config)#route-map set-community permit 10
Switch(config-route-map)#match address 1
Switch(config-route-map)#set community 1111
Switch(config-route-map)#exit
Switch(config)#route-map set-community permit 20
Switch(config-route-map)#match address 2
Switch(config-route-map)#exit
Switch(config)#access-list 1 permit 11.1.0.0 0.0.255.255
Switch(config)#access-list 2 permit 0.0.0.0 255.255.255.255
Switch(config)#exit
Switch#clear ip bgp 16.1.1.6 soft out
In the following sample, configure the MED local preference of the routes from neighbor
16.1.1.6 selectively according to the route community value. All the routes that match the
community list will set MED as 2000, community list com1 permits the route with community
value “100 200 300”or”900 901” to pass. This route may have other community attributes. All the
routes that pass community list com2 will set the local preference as 500. But the route that can’t
pass both com1 and com2 will be rejected.
Switch(config)#router bgp 100
Switch(config-router-bgp)#neighbor 16.1.1.6 remote-as 200
Switch(config-router-bgp)#neighbor 16.1.1.6 route-map match-community in
Switch(config-router-bgp)#exit
Switch(config)#route-map match-community permit 10
Switch(config-route-map)#match community com1