580
SwitchB(config-router-bgp)#network 12.0.0.0
SwitchB(config-router-bgp)#network 13.0.0.0
SwitchB(config-router-bgp)#neighbor 11.1.1.1 remote-as 100
SwitchB(config-router-bgp)#neighbor 12.1.1.3 remote-as 200
SwitchB(config-router-bgp)#neighbor 13.1.1.4 remote-as 200
SwitchB(config-router-bgp)#exit
The configurations of SwitchC are as following:
SwitchC(config)#router bgp 200
SwitchC(config-router-bgp)#network 12.0.0.0
SwitchC(config-router-bgp)#network 13.0.0.0
SwitchC(config-router-bgp)#neighbor 12.1.1.2 remote-as 200
SwitchC(config-router-bgp)#neighbor 13.1.1.4 remote-as 200
SwitchC(config-router-bgp)#exit
The configurations of SwitchD are as following:
SwitchD(config)#router bgp 200
SwitchD(config-router-bgp)#network 13.0.0.0
SwitchD(config-router-bgp)#neighbor 12.1.1.2 remote-as 200
SwitchD(config-router-bgp)#neighbor 13.1.1.3 remote-as 200
SwitchD(config-router-bgp)#exit
Presently, the connection between SwitchB and SwitchA is EBGP, and other
connections with SwitchC and SwitchD are IBGP. SwitchB and SwitchD may have BGP
connection without physical connection. But there is a precondition that these two
switches must have reachable route to each other. This route can be attained through
static route or IGP.
14.8.4.2 Examples 2: configure BGP aggregation
In this sample, configure route aggregation. Firstly, enable command redistribute to
redistribute static route to BGP route table:
SwitchB(config)#ip route 193.0.0.0/24 11.1.12
SwitchB(config)#router bgp 100
SwitchB(config-router-bgp)#redistribute static
When there is at least one route affiliated to the specified range, the following
configuration will create an aggregation route in the BGP route table. The aggregation
route will be regarded as the AS from itself. More detailed route information about
193.0.0.0 will be announced.
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
