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IOS-XE: EBGP peering with Double Advertisement Conditional
12.02 2024 | by massimilianoArchitettura di riferimento reale R1 configuration router bgp 65512 address-family ipv4 vrf EXTERNAL-NET neighbor 10.255.255.3 remote-as 65513 neighbor 10.255.255.3 activate […]
Architettura di riferimento reale
R1 configuration
router bgp 65512
address-family ipv4 vrf EXTERNAL-NET
neighbor 10.255.255.3 remote-as 65513
neighbor 10.255.255.3 activate
neighbor 10.255.255.3 timers 10 30
neighbor 10.255.255.3 default-originate route-map ADV-DEF-CONDITIONAL
neighbor 10.255.255.3 weight 200
neighbor 10.255.255.3 send-community both
neighbor 10.255.255.3 route-map ONLY-AGGREGATE-IN in
neighbor 10.255.255.4 remote-as 65513
neighbor 10.255.255.4 activate
neighbor 10.255.255.4 timers 10 30
neighbor 10.255.255.4 default-originate route-map ADV-DEF-CONDITIONAL
neighbor 10.255.255.4 semd-community both
neighbor 10.255.255.4 route-map ONLY-AGGREGATE-IN in
neighbor 10.255.255.2 remote-as 65512
neighbor 10.255.255.2 activate
neighbor 10.255.255.2 timers 10 30
neighbor 10.255.255.2 send-community both
neighbor 10.255.255.2 next-hop self
neighbor 172.16.1.1 remote-as 100
neighbor 172.16.1.1 activate
neighbor 172.16.1.1 timers 10 30
neighbor 172.16.1.1 ttl-security hops 1
neighbor 172.16.1.1 send-community both
neighbor 172.16.1.1 route-map EXT-NET in
neighbor 172.16.1.1 route-map ONLY-AGGREGATE-OUT out
neighbor 172.16.1.1 maximum-prefix 5000 80 warning-only
!
route-map ADV-DEF-CONDITIONAL permit 10
match ip address prefix-list external-network
route-map ONLY-AGGREGATE-IN permit 10
match ip address prefix-list only-aggregate
route-map EXT-NET permit 10
match ip address prefix-list external-network
route-map ONLY-AGGREGATE-OUT permit 10
match ip address prefix-list only-aggregate
!
ip prefix-list only-aggregate seq 1 permit 10.0.0.0/8
ip prefix-list external-network seq 1 permit 172.16.0.0/16
R2 same configuration to R1
R3 configuration
router bgp 65513
address family ipv4 vrf INTERNAL-NET
aggregate-address 10.0.0.0/8
neighbor 10.255.255.1 remote-as 65512
neighbor 10.255.255.1 activate
neighbor 10.255.255.1 timers 10 30
neighbor 10.255.255.1 send-community both
neighbor 10.255.255.1 route-map ONLY-DEFAULT in
neighbor 10.255.255.1 advertise-map ONLY-AGGREGATE exist-map DEFAULT-EXIST
!
route-map ONLY-DEFAULT permit 10
match ip address prefix-list only-default-route
route-map ONLY-AGGREGATE deny 10
match ip address prefix-list only-default-route
route-map ONLY-AGGREGATE permit 20
match ip address prefix-list only-aggregate
route-map DEFAULT-EXIST
match ip address prefix-list only-default-route
!
ip prefix-list only-default-route seq 1 permit 0.0.0.0/0
ip prefix-list only-aggregate seq 1 permit 10.0.0.0/8
!
R4 same configuration to R3