ipv6 MBGP troubleshooting

[B@B@r]

hello,

every one. i am doing lab of MBGP my configuration are as follow.

i want to change the best path of bgp to external routes how could i do this.

This is my topology.

configuration of R1

ipv6 unicast-routing
ipv6 cef
!
! interface Loopback0
no ip address
ipv6 address 2001:DB8::1/128
!
interface FastEthernet0/0
ip address 192.168.12.1 255.255.255.0
speed auto
duplex auto
ipv6 address 2001:DB8:0:12::1/64

!
router bgp 1
bgp log-neighbor-changes
neighbor 192.168.12.2 remote-as 2
!
address-family ipv4
neighbor 192.168.12.2 activate
exit-address-family
!
address-family ipv6
network 2001:DB8::1/128 route-map clear
neighbor 192.168.12.2 activate
neighbor 192.168.12.2 route-map ipv6_next_hop in
exit-address-family
!
ip forward-protocol nd

!
route-map ipv6_next_hop permit 10
set ipv6 next-hop 2001:DB8:0:12::2
!

Similarly ,

configuration of R2.

ipv6 unicast-routing
ipv6 cef
!
interface Loopback0
no ip address
ipv6 address 2001:DB8::2/128
!
interface FastEthernet0/0
ip address 192.168.12.2 255.255.255.0
speed auto
duplex auto
ipv6 address 2001:DB8:0:12::2/64

!
router bgp 2
bgp router-id 2.2.2.2
bgp log-neighbor-changes
neighbor 192.168.12.1 remote-as 1
!
address-family ipv4
neighbor 192.168.12.1 activate
exit-address-family
!
address-family ipv6
network 2001:DB8::2/128
neighbor 192.168.12.1 activate
neighbor 192.168.12.1 route-map ipv6_next_hop in
exit-address-family
!
ip forward-protocol nd
!
!
route-map ipv6_next_hop permit 10
set ipv6 next-hop 2001:DB8:0:12::1
!
!

Result:

R2

similarly R1

Question:

how to change the attributes of bgp so that the best path will appear in Rib which is not directly connected route as mention in both screenshots.

*> 2001:DB8::2/128  for R1

and

*> 2001:DB8::1/128 for R2

???????????

[Harold Ritter]

By default, eBGP requires the next hop to be directly connected. In your case you have an IPv4 transport to carry IPv6 prefixes. In this case, in addition to changing the next hop to an IPv6 next hop like you do, you also need to configure the disable-connected-check knob on the IPv4 neighbor as follow:

router bgp 1
 neighbor 192.168.12.2 disable-connected-check

router bgp 2
 neighbor 192.168.12.1 disable-connected-check

Note: Best practice would be to use an IPv6 transport instead of an IPv4 transport to carry IPv6 prefixes

Regards,

[Harold Ritter]

Hi B@b@r,

Could you please let me know if that solution worked for you?

Thanks,