BGP route reflector




Hi everyone,

I have been banging my head all day with what seems to be a very simple route reflector configuration.  I am obviously missing something, hope for some input.

I have principally the config below, with R3 being the FR hub and R1 - R2 the spokes. There is a redundant serial link between R3 - R1.
R4 is a 3550 running OSPF and BGP.

I have set up R3 as a route reflector with R1, R2 and R3 as clients, they are all in same BGP AS. They are all running OSPF with full reachability, all BGP neighbors are established /not active/.

I can't get R3 to send BGP routes coming from R2 to R1 and R4. To test stuff I put in a "network 1.1.1.1" under BGP on R3 to to inject the connected network, and that gets advertised fine through BGP to all routers. Routes that need to be reflected don't go through though...

Any ideas?



------                         --------
| R1 |                        | R2  |
------                         -------
                            /
    S1 FR         FR /
                          /
                        /
            ______/
               |   R3   |--|1.1.1.1
                 -------
                   |E0
                   |
                   |
                   |
                ------
                | R4 |
                ------

on R3:
---------------------------------------------
interface Serial0
 ip address 163.1.0.5 255.255.255.0
 encapsulation frame-relay
 frame-relay map ip 163.1.0.3 503 broadcast
 frame-relay map ip 163.1.0.4 504 broadcast
 no frame-relay inverse-arp
!
interface Serial1
 ip address 163.1.45.5 255.255.255.0
 encapsulation ppp
 ip ospf cost 10000
 ppp authentication chap
 ppp chap password 0 CISCO
!
router bgp 200
 bgp log-neighbor-changes
 network 163.1.5.0 mask 255.255.255.0
 neighbor 150.1.4.4 remote-as 200
 neighbor 150.1.4.4 update-source Loopback0
 neighbor 150.1.4.4 route-reflector-client
 neighbor 163.1.0.3 remote-as 200
 neighbor 163.1.0.3 route-reflector-client
 neighbor 163.1.57.7 remote-as 200
 neighbor 163.1.57.7 route-reflector-client
----------------------------------------------

on R2:
----------------------------------------------
interface Serial0
 ip address 163.1.0.3 255.255.255.0
 encapsulation frame-relay
 frame-relay map ip 163.1.0.4 305
 frame-relay map ip 163.1.0.5 305 broadcast
 no frame-relay inverse-arp
!
router bgp 200
 no synchronization
 bgp log-neighbor-changes
 neighbor 163.1.0.5 remote-as 200
 neighbor 163.1.13.1 remote-as 300
 no auto-summary
----------------------------------------------

on R1:
----------------------------------------------
interface Serial0
 ip address 163.1.0.4 255.255.255.0
 encapsulation frame-relay
 frame-relay map ip 163.1.0.3 405
 frame-relay map ip 163.1.0.5 405 broadcast
 no frame-relay inverse-arp
!
interface Serial1
 ip address 163.1.45.4 255.255.255.0
 encapsulation ppp
 clockrate 64000
 ppp authentication chap
 ppp chap password 0 CISCO
!
router bgp 200
 bgp log-neighbor-changes
 neighbor 150.1.5.5 remote-as 200
 neighbor 150.1.5.5 update-source Loopback0
 neighbor 192.10.1.254 remote-as 254
 neighbor 192.10.1.254 password CISCO
----------------------------------------------

on R4:
----------------------------------------------
router bgp 200
 no synchronization
 bgp log-neighbor-changes
 neighbor 163.1.57.5 remote-as 200
 no auto-summary
----------------------------------------------

Comments

  • Well you need to make sure that R3 sees those prefixes as best-paths in other words, it needs *> next to the prefix when you do a "show ip bgp" on R3. If not then you have a next-hop issue most likely.  There are several ways to resolve that, just see what you get.

    Hope that help.s

  • Thanks yandir,

    the problem turned out to be a missed "no synchronization" on R3 and R1.

    I could not put the whole diagram here, but the routes that failed to reflect were coming from a host running only BGP, so there was no way those routes were going to be confirmed by an IGP.

    Thanks for your reply.

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