Concept Guide
BGP global and address family conguration
Implementing BGP is divided into global and address family conguration.
BGP conguration command levels are grouped as high level and address family conguration. All independent commands are grouped at
the beginning of the conguration and followed by separate sub commands specic to each address family.
Following is the order of BGP conguration:
• Global conguration — General conguration that is applied to BGP. For example, conguring BGP timer, Adding additional BGP paths,
etc.
• Address family conguration — Congurations that are applied to a specic address family.
The BGP address family model consists of three address families such as IPv4 unicast, IPv4 multicast, and IPv6 unicast. The default
address family is IPv4 unicast. The neighbors congured under CONFIGURATION-ROUTER-BGP mode is considered to be IPv4 unicast
neighbor. The IPv4 routes are advertised or received irrespective of the address family conguration. To congure a neighbor for IPv4
multicast or IPv6 unicast, you have to create an appropriate address family and explicity activate the neighbor in the respective address
family conguration, as shown the following example conguration.
Example of BGP conguration command levels
Following is an example conguration, which explains the neighbor conguration for all the address families. Also, the conguration shows
how to create address families (IPv4 and IPv6) and activate the neighbors in the address family.
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 conguration 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
Border Gateway Protocol (BGP) 187