BGP Route Reflectors

If you have Dairy setup as the RR and Cherry and Berry setup as the clients, Cherry is going to know about the 22 address. You can prevent this from happening by setting up Dairy as a client on Berry, then let Cherry know about the 22 address by making Cherry a client on Dairy (not sure if this goes against best practices by having more than 1 RR, but I think this is more along the lines of what you were trying to accomplish). Or you could change the lab description to where Berry is the only RR initially and to fix it you make Dairy the RR for both Cherry and Berry.

Below is my final config for all devices.
(Note: I didn't use the pre-built lab since I don't have that IOS, so I built it from scratch with all serial ints. Also, I know the peer-group wasn't completely necessary, but they're fun to work with )

----
!dairy

en
conf t
host Dairy
int lo0
ip add 3.3.3.3 255.255.255.0
int s0/0
desc TO CHERRY
ip add 192.168.13.1 255.255.255.0
no shut
int s0/1
desc TO BERRY
ip add 192.168.23.1 255.255.255.0
no shut
exit
router ospf 1
net 192.168.13.0 0.0.0.255 area 0
net 192.168.23.0 0.0.0.255 area 0
net 3.3.3.0 0.0.0.255 area 0
no auto
exit
router bgp 100
no auto
nei reflector-clients peer-group
nei reflector clients remote-as 100
nei reflector-clients route-reflector-client
nei 192.168.13.2 peer-group reflector-clients
nei 192.168.23.3 peer-group reflector-clients
net 3.3.3.0 mask 255.255.255.0

end

!--------

!cherry

en
conf t
host Cherry
int lo0
ip add 1.1.1.1 255.255.255.0
int s0/1
desc TO DAIRY
ip add 192.168.13.2 255.255.255.0
no shut
int s0/0
desc TO BERRY
ip add 192.168.12.2 255.255.255.0
shut
!^ after establishing connectivity
exit
router ospf 1
net 192.168.13.0 0.0.0.255 area 0
net 192.168.12.0 0.0.0.255 area 0
net 1.1.1.0 0.0.0.255 area 0
no auto
exit
router bgp 100
no auto
nei 192.168.13.1 remote-as 100
net 1.1.1.1 mask 255.255.255.0
end

!--------

!berry

en
conf t
host Berry
int lo0
ip add 2.2.2.2 255.255.255.0
int lo1
ip add 22.22.22.22 255.255.255.0
int s0/1
desc TO DAIRY
ip add 192.168.23.3 255.255.255.0
no shut
int s0/0
desc TO CHERRY
ip add 192.168.12.3 255.255.255.0
shut
!^ after establishing connectivity
exit
router ospf 1
net 2.2.2.0 0.0.0.255 area 0
net 192.168.23.0 0.0.0.255 area 0
net 192.168.12.0 0.0.0.255 area 0
exit
router bgp 100
no auto
nei 192.168.23.1 remote-as 100
net 22.22.22.0 mask 255.255.255.0
net 2.2.2.0 mask 255.255.255.0
end

Hi Jon,

Seems you have some fun with this ;D

The idea of the lab is to learn IBGP Split Horizon. You need IBGP full mesh in order to learn all prefixes, so in this scenario when router Berry advertises something in BGP, router Dairy will learn it because they are IBGP neighbors.

Router Cherry will not learn this prefix since there's no IBGP neighbor adjancency between router Cherry and Berry.

To fix this, router Diary will have to "reflect" the prefix to router Cherry, that's all there is to it

Making berry or cherry a RR doesn't help since they both have only a single BGP neighbor adjacency.

Rene

Right, thats what I was getting at
Making Dairy a RR before checking to see if the 22 route was in Cherry's table kinda defeats the purpose of asking, because after you make it a RR at step 5, it's going to be there. Other than that, cool lab

Glad that it's working, these small labs are nice to do...doesn't take very long.

It Worked.

Thnx ;D