Users Guide

7. Configure the BGP auto-unnumbered neighbor in ROUTER-BGP mode.
OS10-C(config-router-bgp-100)# neighbor unnumbered-auto
OS10-C(config-router-neighbor)# no shutdown
8. Configure the peer group template that the neighbors use to inherit peer-group configuration in ROUTER-NEIGHBOR mode.
This template is applied only to the auto-unnumbered interfaces configured with the ipv6 bgp unnumbered command.
OS10-C(config-router-neighbor)# inherit ibgp-template int-bgp
9. Enable IPv6 address family to advertise IPv6 routes in ROUTER-NEIGHBOR mode.
OS10-C(config-router-neighbor)# address-family ipv6 unicast
OS10-C(config-router-bgp-neighbor-af)# activate
10. Enables EVPN address family to advertise EVPN routes in ROUTER-NEIGHBOR mode.
OS10-C(config-router-neighbor)# address-family l2vpn evpn
OS10-C(config-router-bgp-neighbor-af)# activate
Configure Dual Stack
OS10 supports dual stack for BGPv4 and BGPv6. Dual stack BGP allows simultaneous exchange of the same IPv4 or IPv6
prefixes through different IPv4 and IPv6 peers. You can enable dual stack using the activate command in the corresponding
address-family mode. By default, activate command is enabled for the IPv4 address family for all the neighbors.
If a BGP-v4 neighbor wants to carry ipv6 prefix information, it activates the IPv6 address-family. For a BGP-v6 neighbor to
carry ipv4 prefix, it activates the IPv4 address-family.
1. Enable support for the IPv6 unicast family in CONFIG-ROUTER-BGP mode.
address family ipv6 unicast
2. Enable IPv6 unicast support on a BGP neighbor/template in CONFIG-ROUTER-BGP-AF mode.
activate
Configure administrative distance
Routers use administrative distance to determine the best path between two or more routes to reach the same destination.
Administrative distance indicates the reliability of the route; the lower the administrative distance, the more reliable the route. If
the routing table manager (RTM) receives route updates from one or more routing protocols for a single destination, it chooses
the best route based on the administrative distance.
You can assign an administrative distance for the following BGP routes using the distance bgp command:
● External BGP (eBGP) routes
●
Internal BGP (iBGP) routes
● Local routes
If you do not configure the administrative distance for BGP routes, the following default values are used:
● eBGP—20
● iBGP—200
● local routes—200
To change the administrative distance for BGP, use the following command:
distance bgp external-distance internal-distance local-distance
Configure administrative distance
1. Enable BGP and assign the AS number in CONFIGURATION mode, from 0.1 to 65535.65535 or 1 to 4294967295.
OS10# configure terminal
OS10(config)# router bgp 100
Layer 3
805