Setup Guide

be IPv4 unicast neighbor. To configure a neighbor for IPv4 multicast or IPv6 unicast, you have to explicity activate the neighbor
in the respective address family configuration, as shown the following example configuration.
Example of BGP configuration command levels
Following is an example configuration, which explains the neighbor configuration for all the address families.
DellEMC(conf)#router bgp 10
DellEMC(conf-router_bgp)#neighbor 20.20.20.1 remote-as 200
DellEMC(conf-router_bgp)#neighbor 20.20.20.1 no shutdown
DellEMC(conf-router_bgp)#neighbor 2001::1 remote-as 200
DellEMC(conf-router_bgp)#neighbor 2001::1 no shutdown
DellEMC(conf-router_bgp)#address-family ipv4 multicast
DellEMC(conf-router_bgp_af)#neighbor 20.20.20.1 activate
DellEMC(conf-router_bgp_af)#exit
DellEMC(conf-router_bgp)#address-family ipv6 unicast
DellEMC(conf-router_bgpv6_af)#neighbor 2001::1 activate
DellEMC(conf-router_bgpv6_af)#exit
BGP global configuration default values
By default, BGP is disabled. The following table displays the default values for BGP on Dell EMC Networking OS.
Table 9. BGP Default Values
Item Default
BGP Neighbor Adjacency changes All BGP neighbor changes are logged.
Fast External Fallover feature Disabled
Graceful Restart feature Disabled
Local preference 100
MED 0
Route Flap Damping Parameters
half-life = 15 minutes
reuse = 750
suppress = 2000
max-suppress-time = 60 minutes
Distance
external distance = 20
internal distance = 200
local distance = 200
Timers
keepalive = 60 seconds
holdtime = 180 seconds
Add-path Disabled
Implement BGP with Dell EMC Networking OS
The following sections describe how to implement BGP on Dell EMC Networking OS.
Additional Path (Add-Path) Support
The add-path feature reduces convergence times by advertising multiple paths to its peers for the same address prefix without
replacing existing paths with new ones. By default, a BGP speaker advertises only the best path to its peers for a given address
prefix. If the best path becomes unavailable, the BGP speaker withdraws its path from its local RIB and recalculates a new best
path. This situation requires both IGP and BGP convergence and can be a lengthy process. BGP add-path also helps switchover
to the next new best path when the current best path is unavailable.
Border Gateway Protocol (BGP)
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