IBGP to EBGP unable to ping

lttlnnj · ‎06-08-2018

I'm trying to ping R4 from R1(and vice versa) but I am completely stuck and clueless what to do next.
R2---EBGP---R4

R3---EBGP---R4

R1 and R5 is acting like a Core from a LAN network using loopback. I can ping R1 from R5 and vice versa. Can anyone help me point on what I am doing wrong, please?

And also, what's the best way to make 172.16.17.4 the primary path when going to R1/R5 from R4?

R1

interface Loopback0
ip address 10.7.1.1 255.255.255.0
ip ospf network point-to-point
!
interface GigabitEthernet0/0
ip address 10.255.0.52 255.255.0.0
shutdown
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/1
ip address 10.7.5.1 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/2
ip address 10.7.6.1 255.255.255.252
duplex auto
speed auto
media-type rj45
!
router ospf 1
router-id 10.7.1.1
network 10.7.1.1 0.0.0.0 area 0
network 10.7.5.1 0.0.0.0 area 0
network 10.7.6.1 0.0.0.0 area 0

R2

interface GigabitEthernet0/1
ip address 10.7.5.2 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/2
ip address 10.7.7.2 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/3
description Head Office R1->Service Provider
ip address 172.16.17.5 255.255.255.252
duplex auto
speed auto
media-type rj45
!
router ospf 1
network 10.7.5.2 0.0.0.0 area 0
network 10.7.7.2 0.0.0.0 area 0
!
router bgp 65007
bgp log-neighbor-changes
network 10.7.1.0 mask 255.255.255.0
network 10.8.1.0 mask 255.255.255.0
neighbor 172.16.17.6 remote-as 4700
neighbor 172.16.17.6 route-map PRIMARYPATH in
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
ip route 172.16.17.0 255.255.255.0 Null0
!
!
route-map PRIMARYPATH permit 10
set local-preference 150

R3

interface GigabitEthernet0/2
description Head Office R2->Core
ip address 10.7.6.2 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/3
no ip address
shutdown
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/4
description Head Office R2->Service Provider
ip address 172.16.17.1 255.255.255.252
duplex auto
speed auto
media-type rj45
!
router ospf 1
network 10.7.6.2 0.0.0.0 area 0
!
router bgp 65007
bgp log-neighbor-changes
network 10.7.1.0
network 10.7.1.0 mask 255.255.255.0
neighbor 172.16.17.2 remote-as 4700
neighbor 172.16.17.2 route-map SECONDARYPATH in
!
ip forward-protocol nd
!
!
no ip http server
no ip http secure-server
ip route 172.16.17.0 255.255.255.0 Null0
!
!
route-map SECONDARYPATH permit 10
set local-preference 125

R4

interface GigabitEthernet0/3
description Service Provider -> Head Office R1
ip address 172.16.17.6 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/4
description Service Provider -> Head Office R2
ip address 172.16.17.2 255.255.255.252
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/5
no ip address
shutdown
duplex auto
speed auto
media-type rj45
!
interface GigabitEthernet0/6
no ip address
shutdown
duplex auto
speed auto
media-type rj45
!
router bgp 4700
bgp log-neighbor-changes
network 172.16.17.0 mask 255.255.255.252
network 172.16.17.4 mask 255.255.255.252
neighbor 172.16.17.1 remote-as 65007
neighbor 172.16.17.1 default-originate
neighbor 172.16.17.5 remote-as 65007
neighbor 172.16.17.5 default-originate
!

R5

interface Loopback0
ip address 10.8.1.1 255.255.255.0
ip ospf network point-to-point
!
interface GigabitEthernet0/2
ip address 10.7.7.1 255.255.255.252
duplex auto
speed auto
media-type rj45
!
router ospf 1
router-id 10.8.1.1
network 10.7.7.1 0.0.0.0 area 0
network 10.8.1.1 0.0.0.0 area 0
!

R4 show ip bgp

Network Next Hop Metric LocPrf Weight Path
0.0.0.0 0.0.0.0 0 i
* 10.7.1.0/24 172.16.17.5 2 0 65007 i
*> 172.16.17.1 2 0 65007 i
*> 10.8.1.0/24 172.16.17.5 2 0 65007 i
*> 172.16.17.0/30 0.0.0.0 0 32768 i
*> 172.16.17.4/30 0.0.0.0 0 32768 i

R4 show ip route

10.0.0.0/24 is subnetted, 2 subnets
B 10.7.1.0 [20/2] via 172.16.17.1, 00:44:05
B 10.8.1.0 [20/2] via 172.16.17.5, 00:44:04
172.16.0.0/16 is variably subnetted, 4 subnets, 2 masks
C 172.16.17.0/30 is directly connected, GigabitEthernet0/4
L 172.16.17.2/32 is directly connected, GigabitEthernet0/4
C 172.16.17.4/30 is directly connected, GigabitEthernet0/3
L 172.16.17.6/32 is directly connected, GigabitEthernet0/3

Georg Pauwen · ‎06-08-2018

You need to redistribute BGP into OSPF, otherwise R1 does not know how to get to R4...

paul driver · ‎06-10-2018

Hello

1- redistribute a default into ospf from bgp/ospf rtrs based on the default your bgp rtrs are receiving from R4

2) create an ibgp connection between r2 -r3 this will then allow you to use the local preference you have setup

3) In r4 set default weight preference to both ebgp links with a higher metric given to 172.16.17.4/30 link

Lasty FYI

R2-R5 10.7.7.0/30 shows it’s in area0 not area1 as your topology is showing

res

paul

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Kind Regards
Paul