Quick Notes - BGP Neighbors

* This network provides full reachability and uses one route-map to change the preference of 200 network.

[R1]
interface Loopback0
 ip address 1.1.1.1 255.255.255.255
!
interface Serial0/0
 ip address 200.0.0.1 255.255.255.0
 serial restart-delay 0
!
interface Serial0/1
 ip address 10.0.0.1 255.255.255.0
 serial restart-delay 0
!
interface Serial0/2
 ip address 189.0.0.1 255.255.255.0
 serial restart-delay 0
!
router bgp 1
 no synchronization
 bgp log-neighbor-changes
 network 10.0.0.0 mask 255.255.255.0
 network 189.0.0.0 mask 255.255.255.0
 network 200.0.0.0
 neighbor 2.2.2.2 remote-as 2
 neighbor 2.2.2.2 ebgp-multihop 2
 neighbor 2.2.2.2 update-source Loopback0
 neighbor 3.3.3.3 remote-as 3
 neighbor 3.3.3.3 ebgp-multihop 2
 neighbor 3.3.3.3 update-source Loopback0
 neighbor 10.0.0.2 remote-as 1
 neighbor 10.0.0.2 next-hop-self
 no auto-summary
!
ip route 2.2.2.2 255.255.255.255 200.0.0.2
ip route 3.3.3.3 255.255.255.255 189.0.0.3

[R2]
interface Serial0/1
 ip address 10.0.0.2 255.255.255.0
 serial restart-delay 0
!
router bgp 1
 no synchronization
 bgp log-neighbor-changes
 neighbor 10.0.0.1 remote-as 1
 no auto-summary
!
ip route 0.0.0.0 0.0.0.0 10.0.0.1

[R3]
interface Loopback0
 ip address 2.2.2.2 255.255.255.255
!
interface Serial0/0
 ip address 200.0.0.2 255.255.255.0
 serial restart-delay 0
!
interface Serial0/3
 ip address 100.0.0.2 255.255.255.0
 serial restart-delay 0
!
router bgp 2
 no synchronization
 bgp log-neighbor-changes
 network 100.0.0.0 mask 255.255.255.0
 network 200.0.0.0
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 ebgp-multihop 2
 neighbor 1.1.1.1 update-source Loopback0
 neighbor 3.3.3.3 remote-as 3
 neighbor 3.3.3.3 ebgp-multihop 2
 neighbor 3.3.3.3 update-source Loopback0
 neighbor 3.3.3.3 route-map metricToR4 out
 no auto-summary
!
ip route 1.1.1.1 255.255.255.255 200.0.0.1
ip route 3.3.3.3 255.255.255.255 100.0.0.3
!
ip prefix-list prefix200 seq 5 permit 200.0.0.0/24
!
route-map metricToR4 permit 10
 match ip address prefix-list prefix200
 set metric 100
!
route-map metricToR4 permit 20

[R4]
interface Loopback0
 ip address 3.3.3.3 255.255.255.255
!
interface Loopback1
 ip address 48.0.1.1 255.255.255.0
!
interface Serial0/2
 ip address 189.0.0.3 255.255.255.0
 serial restart-delay 0
!
interface Serial0/3
 ip address 100.0.0.3 255.255.255.0
 serial restart-delay 0
!
router bgp 3
 no synchronization
 bgp log-neighbor-changes
 network 48.0.1.0 mask 255.255.255.0
 network 100.0.0.0 mask 255.255.255.0
 network 189.0.0.0 mask 255.255.255.0
 neighbor 1.1.1.1 remote-as 1
 neighbor 1.1.1.1 ebgp-multihop 2
 neighbor 1.1.1.1 update-source Loopback0
 neighbor 2.2.2.2 remote-as 2
 neighbor 2.2.2.2 ebgp-multihop 2
 neighbor 2.2.2.2 update-source Loopback0
 no auto-summary
!
ip route 1.1.1.1 255.255.255.255 189.0.0.1
ip route 2.2.2.2 255.255.255.255 100.0.0.2


[*] BGP Resources


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