Connectivity Guide

(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 congure 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
Congure 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
2 Enter ADDRESS-FAMILY mode.
IPv4:
OS10(config-router-bgp-100)# address-family ipv4 unicast
OS10(configure-router-bgpv4-af)#
IPv6:
OS10(config-router-bgp-100)# address-family ipv6 unicast
OS10(configure-router-bgpv6-af)#
3 Change the administrative distance for BGP.
IPv4:
OS10(configure-router-bgpv4-af)# distance bgp 21 200 200
IPv6:
OS10(configure-router-bgpv6-af)# distance bgp 21 201 250
The example below provides the conguration for non-default VRF.
OS10(config-router-bgp-100)# vrf blue
OS10(config-router-bgp-100-vrf)# address-family ipv4 unicast
OS10(configure-router-bgpv4-vrf-af)# distance bgp 21 200 200
OS10(config-router-bgp-100-vrf)# address-family ipv6 unicast
OS10(configure-router-bgpv6-vrf-af)# distance bgp 21 201 250
Peer templates
To congure multiple BGP neighbors at one time, create and populate a BGP peer template. An advantage of conguring peer templates is
that members of a peer template inherit the conguration properties of the template and share update policy. Always create a peer
template and assign a name to it before adding members to the peer template. Create a peer template before conguring any route policies
for the template.
Layer 3
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