BGP4 and Address-Family IPv4 Unicast Mode

You can configure BGP4 unicast routes from the address-family IPv4 unicast configuration level.

You can access the address-family IPv4 unicast configuration level from BGP configuration mode.
device(config)# router bgp
device(config-bgp-router)# address-family ipv4 unicast 
device(config-bgp-ipv4u)#
Note

Note

The commands that are available from the address-family IPv4 unicast configuration level are also available from the address-family IPv6 unicast configuration level. Each configuration level allows you to access commands that apply only to that particular address family.

Several configuration options are available from IPv4 address family unicast configuration mode.
device(config-bgp-router)# address-family ipv4 unicast
 
device(config-bgp-ipv4u)# ?
Possible completions:
  aggregate-address               Configure BGP aggregate entries
  always-propagate                Allow readvertisement of best BGP routes not
                                  in IP Forwarding table
  bgp-redistribute-internal       Allow redistribution of iBGP routes into IGPs
  client-to-client-reflection     Configure client to client route reflection
  dampening                       Enable route-flap dampening
  default-information-originate   Originate Default Information
  default-metric                  Set metric of redistributed routes
  graceful-restart                Enables the BGP graceful restart capability
  maximum-paths                   Forward packets over multiple paths
  multipath                       Enable multipath for ibgp or ebgp neighbors
                                  only
  neighbor                        Specify a neighbor router
  network                         Specify a network to announce via BGP
  next-hop-enable-default         Enable default route for BGP next-hop lookup
  next-hop-mpls                   Changes for IPoMPLS route download, pkt path.
  next-hop-recursion              Perform next-hop recursive lookup for BGP
                                  route
  redistribute                    Redistribute information from another
                                  routing protocol
  rib-route-limit                 Limit BGP rib count in routing table
  static-network                  Special network that do not depends on IGP
                                  and always treat as best route in BGP
  table-map                       Map external entry attributes into routing
                                  table
  update-time                     Configure igp route update interval