IBGP LAB ROUTING – REDUNDANT LINK
Here is a Lab scenerio providing 3 router within an IBGP. Creating a primary and secondary redundant
link using local precedence value with route-map statement.
R0 router is to be the primary link and R2 is the redundant link.
R1 is to tag routes going to neighbor R0 with a preference value of 200, thus making it a primary link
since the defaulf preference value is 100 and the highest pref set than 100 will become the main link.
RO
interface Loopback0
ip address 100.0.0.1 255.255.255.255
!
interface FastEthernet0/0
ip address 192.168.0.1 255.255.255.252
!
interface FastEthernet0/1
ip address 192.168.0.5 255.255.255.252
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 ebgp-multihop 2
neighbor 1.1.1.1 update-source Loopback0
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 ebgp-multihop 2
neighbor 2.2.2.2 update-source Loopback0
neighbor 192.168.0.2 remote-as 100
neighbor 192.168.0.6 remote-as 100
no auto-summary
!
ip route 1.1.1.1 255.255.255.255 192.168.0.2
ip route 2.2.2.2 255.255.255.255 192.168.0.6
!
!
R1
interface Loopback1
ip address 1.1.1.1 255.255.255.255
!
interface FastEthernet0/0
ip address 192.168.0.2 255.255.255.252
!
interface FastEthernet0/1
ip address 192.168.0.9 255.255.255.252
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 2.2.2.2 remote-as 100
neighbor 2.2.2.2 ebgp-multihop 2
neighbor 2.2.2.2 update-source Loopback1
neighbor 100.0.0.1 remote-as 100
neighbor 100.0.0.1 ebgp-multihop 2
neighbor 100.0.0.1 update-source Loopback1
neighbor 192.168.0.1 remote-as 100
neighbor 192.168.0.1 route-map PREFERENCE in
neighbor 192.168.0.10 remote-as 100
no auto-summary
!
route-map PREFERENCE permit 10
set local-preference 200
!
ip route 2.2.2.2 255.255.255.255 192.168.0.10
ip route 100.0.0.1 255.255.255.255 192.168.0.1
R2
interface Loopback2
ip address 2.2.2.2 255.255.255.0
!
interface FastEthernet0/0
ip address 192.168.0.6 255.255.255.252
!
interface FastEthernet0/1
ip address 192.168.0.10 255.255.255.252
!
router bgp 100
no synchronization
bgp log-neighbor-changes
neighbor 1.1.1.1 remote-as 100
neighbor 1.1.1.1 ebgp-multihop 2
neighbor 1.1.1.1 update-source Loopback2
neighbor 100.0.0.1 remote-as 100
neighbor 100.0.0.1 ebgp-multihop 2
neighbor 100.0.0.1 update-source Loopback2
neighbor 192.168.0.5 remote-as 100
neighbor 192.168.0.9 remote-as 100
no auto-summary
!
ip route 1.1.1.1 255.255.255.255 192.168.0.9
ip route 100.0.0.1 255.255.255.255 192.168.0.5