Bgp Confederation: Example - Cisco NCS 6000 Series Configuration Manual

BGP Confederation: Example

BGP Confederation: Example
The following is a sample configuration that shows several peers in a confederation. The confederation consists
of three internal autonomous systems with autonomous system numbers 6001, 6002, and 6003. To the BGP
speakers outside the confederation, the confederation looks like a normal autonomous system with autonomous
system number 666 (specified using the bgp confederation identifier command).
In a BGP speaker in autonomous system 6001, the bgp confederation peers command marks the peers from
autonomous systems 6002 and 6003 as special eBGP peers. Hence, peers 171. 69.232.55 and 171. 69.232.56
get the local preference, next hop, and MED unmodified in the updates. The router at 160. 69.69.1 is a normal
eBGP speaker, and the updates received by it from this peer are just like a normal eBGP update from a peer
in autonomous system 666.
router bgp 6001
bgp confederation identifier 666
bgp confederation peers
address-family ipv4 unicast
address-family ipv4 unicast
address-family ipv4 unicast
In a BGP speaker in autonomous system 6002, the peers from autonomous systems 6001 and 6003 are
configured as special eBGP peers. Peer 170. 70.70.1 is a normal iBGP peer, and peer 199.99.99.2 is a normal
eBGP peer from autonomous system 700.
router bgp 6002
bgp confederation identifier 666
bgp confederation peers
address-family ipv4 unicast
address-family ipv4 unicast
address-family ipv4 unicast
Routing Configuration Guide for Cisco NCS 6000 Series Routers, IOS XR Release 6.4.x
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route-policy pass-all in
route-policy pass-all out
6002
6003
exit
neighbor 171.69.232.55
remote-as 6002
exit
neighbor 171.69.232.56
remote-as 6003
exit
neighbor 160.69.69.1
remote-as 777
6001
6003
exit
neighbor 170.70.70.1
remote-as 6002
exit
neighbor 171.69.232.57
remote-as 6001
exit
neighbor 171.69.232.56
remote-as 6003
exit
Implementing BGP