Concept Guide
Figure 26. Congure IPv6 NH to advertise IPv6 prex over IPv4 neighbor
To enable BGP to pick the next hop IPv6 address automatically for IPv6 prex advertised over an IPv4 neighbor, use the following
commands.
• Enable the system to pick the next hop IPv6 address dynamically for IPv6 prex advertised over an IPv4 neighbor.
ROUTER-BGP mode mode
neighbor {ip–address | peer-group-name} auto-local-address
Enter either the neighbor IP address or the name of the peer group.
NOTE: If outbound policy is applied along with auto-local-address enabled, then policy takes precedence.
Example conguration of BGP to automatically pick IPv6 address automatically for IPv6 prex advertised over an IPv4 neighbor
The following example conguration demonstrates how to congure BGP to automatically pick IPv6 address for IPv6 prex advertised over
an IPv4 neighbor.
Example conguration performed in R1
DellEMC# configure terminal
DellEMC(conf)# router bgp 655
DellEMC(conf-router_bgp)# neighbor 10.1.1.2 remote-as 20
DellEMC(conf-router_bgp)# neighbor 10.1.1.2 auto-local-address
DellEMC(conf-router_bgp)# neighbor 10.1.1.2 no shutdown
DellEMC(conf-router_bgp)# bgp router-id 1.1.1.1
DellEMC(conf-router_bgp)# address-family ipv6 unicast
DellEMC(conf-router_bgpv6_af)# neighbor 10.1.1.2 activate
DellECM(conf-router_bgpv6_af)# exit
Conguring the auto-local-address for a neighbor will dynamically pick the local BGP interface IPv6 address (2001::1/64) as a the next hop
for all the updates over IPv4 neighbor congured under IPv6 address family. If the auto-local-address is not congured, the IPv4 mapped
IPv6 address (10.1.1.1) as a next hop.
Following is the show running-config command output for the above conguration.
DellEMC# show running-config bgp
!
router bgp 655
bgp router-id 1.1.1.1
neighbor 10.1.1.2 remote-as 20
neighbor 10.1.1.2 auto-local-address
neighbor 10.1.1.2 no shutdown
!
address-family ipv6 unicast
neighbor 10.1.1.2 activate
exit-address-family
!
Example conguration performed in R2
DellEMC# configure terminal
DellEMC(conf)# router bgp 20
254
Border Gateway Protocol (BGP)