I'm very confused by the way you have this setup. It looks to me that you are setting R2 up to be a route reflector for R3 and you are setting up R3 to be a route reflector for R2. My question is why? If you are setting up two route reflectors in the same AS and they are going to speak to each other you must set each route reflector up in the same cluster. This allows for each router reflector to ignore reflected routes from the other route reflector, thus avoiding potential routing loops. I'll show you a couple of examples below and explain them.
In the first scenarion we will have three devices: R1, R2, and R3. R2 will be the route reflector for route reflector clients R1 and R3. We will use the loopback addresses of each device for connectivity. The loopback addresses must be known to each device by the IGP you are running. AS# - 100 R1 Lo0 - 1.1.1.1 R2 Lo0 - 2.2.2.2 R3 Lo0 - 3.3.3.3 Note: The route reflector client command is placed on the route reflecting device not the route reflector client device. We will first setup the route reflector: R2#conf t R2(config)#router bgp 100 R2(config-router)#neighbor 1.1.1.1 remote-as 100 R2(config-router)#neighbor 1.1.1.1 update-source lo0 R2(config-router)#neighbor 1.1.1.1 route-reflector-client R2(config-router)#neighbor 3.3.3.3 remote-as 100 R2(config-router)#neighbor 3.3.3.3 update-source lo0 R2(config-router)#neighbor 3.3.3.3 route-reflector-client R2(config-router)#exit R2(config)#exit R2# We will now setup the route reflector clients: R1#conf t R1(config)#router bgp 100 R1(config-router)#neighbor 2.2.2.2 remote-as 100 R1(config-router)#neighbor 2.2.2.2 update-source lo0 R1(config-router)#exit R1(config)#exit R1# R3#conf t R3(config)#router bgp 100 R3(config-router)#neighbor 2.2.2.2 remote-as 100 R3(config-router)#neighbor 2.2.2.2 update-source lo0 R3(config-router)#exit R3(config)#exit R3# Explination: Route reflector clients are only configured in the way a normal IBGP connection would be configured. The reason we used the update-source command on the connection is to tell the local device what source address to use when sending the BGP packets. If we had not used the update-source command, the router would have used the address of the interface the packet was going out. This would have caused problems because the remote device was expecting packets from the loopback address, since we used the loopback address in the neighbor statement on the remote device. The route reflecting device is the only device configured with the route-reflector client command. The reason is that the command tells the route reflecting device which devices to reflect routes too. In the next scenario we will have four devices: R1, R2, R3, and R4. We will use two route reflectors in the same AS so we don't have a single point of failure. We will configure R2 and R3 as the route reflectors and R1 and R4 as the clients to both route reflectors. Once again we will use loopback addresses on each device. Make sure the IGP is advertising these loopback addresses to the other devices. AS# - 100 Cluster ID - 1 R1 Lo0 - 1.1.1.1 R2 Lo0 - 2.2.2.2 R3 Lo0 - 3.3.3.3 R4 Lo0 - 4.4.4.4 We will first setup the route reflector: R2#conf t R2(config)#router bgp 100 R2(config-router)#bgp cluster-id 1 R2(config-router)#neighbor 1.1.1.1 remote-as 100 R2(config-router)#neighbor 1.1.1.1 update-source lo0 R2(config-router)#neighbor 1.1.1.1 route-reflector-client R2(config-router)#neighbor 4.4.4.4 remote-as 100 R2(config-router)#neighbor 4.4.4.4 update-source lo0 R2(config-router)#neighbor 4.4.4.4 route-reflector-client R2(config-router)#neighbor 3.3.3.3 remote-as 100 R2(config-router)#neighbor 3.3.3.3 update-source lo0 R2(config-router)#exit R2(config)#exit R2# R3(config)#router bgp 100 R3(config-router)#bgp cluster-id 1 R3(config-router)#neighbor 1.1.1.1 remote-as 100 R3(config-router)#neighbor 1.1.1.1 update-source lo0 R3(config-router)#neighbor 1.1.1.1 route-reflector-client R3(config-router)#neighbor 4.4.4.4 remote-as 100 R3(config-router)#neighbor 4.4.4.4 update-source lo0 R3(config-router)#neighbor 4.4.4.4 route-reflector-client R3(config-router)#neighbor 2.2.2.2 remote-as 100 R3(config-router)#neighbor 2.2.2.2 update-source lo0 R3(config-router)#exit R3(config)#exit R3# We will now setup the route reflector clients: R1#conf t R1(config)#router bgp 100 R1(config-router)#neighbor 2.2.2.2 remote-as 100 R1(config-router)#neighbor 2.2.2.2 update-source lo0 R1(config-router)#neighbor 3.3.3.3 remote-as 100 R1(config-router)#neighbor 3.3.3.3 update-source lo0 R1(config-router)#exit R1(config)#exit R1# R4#conf t R4(config)#router bgp 100 R4(config-router)#neighbor 2.2.2.2 remote-as 100 R4(config-router)#neighbor 2.2.2.2 update-source lo0 R4(config-router)#neighbor 3.3.3.3 remote-as 100 R4(config-router)#neighbor 3.3.3.3 update-source lo0 R4(config-router)#exit R4(config)#exit R4# Explination: The route reflector client devices are configure with an IBGP connection to each of the route reflecting devices. The route reflecting devices are configured with IBGP connections to all devices, but only have the route-reflector-client command on connections to the clients. The reason for the bgp cluster id is to inform the route reflecting devices if they receive a reflected route from another route reflector in the same cluster to ignore it. This helps in preventing routing loops. I hope this explination helps. Carl Timm, CCIE #7149 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=54240&t=54194 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
