BGP

Border Gateway Protocol (BGP) is the de facto standard exterior gateway protocol used to exchange routing information between autonomous systems (AS) on the Internet and in large enterprise networks. It’s a path-vector protocol that makes routing decisions based on network policies, rules, and path attributes rather than just metrics, enabling fine-grained control over traffic flows and routing policies. BGP supports multiple address families including IPv4 unicast, IPv6 unicast, and L2VPN EVPN, making it essential for modern multi-service networks and MPLS VPN deployments.

Diagram

Classes

routing (iosxe.devices.configuration)

Name	Type	Constraint	Mandatory	Default Value
bgp	Class	`[bgp]`	No

bgp (iosxe.devices.configuration.routing)

Name	Type	Constraint	Mandatory
as_number	Integer		Yes
default_ipv4_unicast	Boolean	`true`, `false`	No
log_neighbor_changes	Boolean	`true`, `false`	No
router_id_loopback	Integer		No
address_family	Class	`[address_family]`	No
neighbors	List	`[neighbors]`	No

address_family (iosxe.devices.configuration.routing.bgp)

Name	Type	Constraint	Mandatory
ipv4_unicast	Class	`[ipv4_unicast]`	No
ipv6_unicast	Class	`[ipv6_unicast]`	No
l2vpn_evpn	Class	`[l2vpn_evpn]`	No

neighbors (iosxe.devices.configuration.routing.bgp)

Name	Type	Constraint	Mandatory
ip	IP		Yes
remote_as	Integer		Yes
description	String		No
shutdown	Boolean	`true`, `false`	No
cluster_id	IP		No
disable_connected_check	Boolean	`true`, `false`	No
fall_over_default_enable	Boolean	`true`, `false`	No
fall_over_default_route_map	String		No
fall_over_bfd	Boolean	`true`, `false`	No
fall_over_bfd_multi_hop	Boolean	`true`, `false`	No
fall_over_bfd_single_hop	Boolean	`true`, `false`	No
fall_over_bfd_check_control_plane_failure	Boolean	`true`, `false`	No
fall_over_bfd_strict_mode	Boolean	`true`, `false`	No
fall_over_maximum_metric_route_map	String		No
local_as	Integer		No
local_as_no_prepend	Boolean	`true`, `false`	No
local_as_replace_as	Boolean	`true`, `false`	No
local_as_dual_as	Boolean	`true`, `false`	No
log_neighbor_changes	Boolean	`true`, `false`	No
password_type	Integer	min: `0`, max: `7`	No
password	String		No
peer_group	String		No
timers_keepalive	Integer	min: `0`, max: `3600`	No
timers_holdtime	Integer	min: `0`, max: `3600`	No
timers_minimum_neighbor_holdtime	Integer	min: `0`, max: `3600`	No
ttl_security_hops	Integer	min: `0`, max: `254`	No
update_source_loopback	Integer		No
ebgp_multihop	Boolean	`true`, `false`	No
ebgp_multihop_max_hop	Integer	min: `1`, max: `255`	No

ipv4_unicast (iosxe.devices.configuration.routing.bgp.address_family)

Name	Type	Constraint	Mandatory
aggregate_addresses	List	`[aggregate_addresses]`	No
networks	List	`[networks]`	No
neighbors	List	`[neighbors]`	No
vrfs	List	`[vrfs]`	No
redistribute	Class	`[redistribute]`	No
admin_distances	List	`[admin_distances]`	No
distance_bgp_external	Integer	min: `1`, max: `255`	No
distance_bgp_internal	Integer	min: `1`, max: `255`	No
distance_bgp_local	Integer	min: `1`, max: `255`	No

ipv6_unicast (iosxe.devices.configuration.routing.bgp.address_family)

Name	Type	Constraint	Mandatory
networks	List	`[networks]`	No
vrfs	List	`[vrfs]`	No
neighbors	List	`[neighbors]`	No
redistribute	Class	`[redistribute]`	No

l2vpn_evpn (iosxe.devices.configuration.routing.bgp.address_family)

Name	Type	Constraint	Mandatory	Default Value
neighbors	List	`[neighbors]`	No

aggregate_addresses (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
mask	IP		Yes

networks (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory
network	IP		Yes
mask	IP		No
route_map	String		No
backdoor	Boolean	`true`, `false`	No

neighbors (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory
ip	IP		Yes
activate	Boolean	`true`, `false`	No
send_community	Choice	`both`, `extended`, `standard`	No
route_reflector_client	Boolean	`true`, `false`	No
soft_reconfiguration	Choice	`inbound`	No
default_originate	Boolean	`true`, `false`	No
default_originate_route_map	String		No
route_maps	List	`[route_maps]`	No

vrfs (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory
vrf	String		Yes
advertise_l2vpn_evpn	Boolean	`true`, `false`	No
router_id_loopback	Integer		No
aggregate_addresses	List	`[aggregate_addresses]`	No
networks	List	`[networks]`	No
neighbors	List	`[neighbors]`	No
redistribute	Class	`[redistribute]`	No
admin_distances	List	`[admin_distances]`	No
distance_bgp_external	Integer	min: `1`, max: `255`	No
distance_bgp_internal	Integer	min: `1`, max: `255`	No
distance_bgp_local	Integer	min: `1`, max: `255`	No

redistribute (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory	Default Value
connected	Boolean	`true`, `false`	No
static	Boolean	`true`, `false`	No

admin_distances (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast)

Name	Type	Constraint	Mandatory
distance	Integer	min: `1`, max: `255`	Yes
source_ip	IP		Yes
wildcard	IP		Yes
acl	String		No

networks (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast)

Name	Type	Constraint	Mandatory
prefix	IP		Yes
route_map	String		No
backdoor	Boolean	`true`, `false`	No

vrfs (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast)

Name	Type	Constraint	Mandatory
vrf	String		Yes
advertise_l2vpn_evpn	Boolean	`true`, `false`	No
networks	List	`[networks]`	No
redistribute	Class	`[redistribute]`	No

neighbors (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast)

Name	Type	Constraint	Mandatory
ip	IP		Yes
activate	Boolean	`true`, `false`	No
send_community	Choice	`both`, `extended`, `standard`	No
route_reflector_client	Boolean	`true`, `false`	No
soft_reconfiguration	Choice	`inbound`	No
default_originate	Boolean	`true`, `false`	No
default_originate_route_map	String		No

redistribute (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast)

Name	Type	Constraint	Mandatory	Default Value
connected	Boolean	`true`, `false`	No
static	Boolean	`true`, `false`	No

neighbors (iosxe.devices.configuration.routing.bgp.address_family.l2vpn_evpn)

Name	Type	Constraint	Mandatory
ip	IP		Yes
activate	Boolean	`true`, `false`	No
send_community	Choice	`both`, `extended`, `standard`	No
route_reflector_client	Boolean	`true`, `false`	No
soft_reconfiguration	Choice	`inbound`	No

route_maps (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.neighbors)

Name	Type	Constraint	Mandatory	Default Value
direction	Choice	`in`, `out`	Yes
name	String		Yes

aggregate_addresses (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs)

Name	Type	Constraint	Mandatory	Default Value
address	IP		Yes
mask	IP		Yes

networks (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs)

Name	Type	Constraint	Mandatory
network	IP		Yes
mask	IP		No
route_map	String		No
backdoor	Boolean	`true`, `false`	No

neighbors (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs)

Name	Type	Constraint	Mandatory
ip	IP		Yes
remote_as	Integer		Yes
description	String		No
shutdown	Boolean	`true`, `false`	No
cluster_id	IP		No
log_neighbor_changes	Boolean	`true`, `false`	No
password_type	Integer	min: `0`, max: `7`	No
password	String		No
timers_keepalive	Integer	min: `0`, max: `3600`	No
timers_holdtime	Integer	min: `0`, max: `3600`	No
timers_minimum_holdtime	Integer	min: `0`, max: `3600`	No
fall_over_default_route_map	String		No
fall_over_bfd	Boolean	`true`, `false`	No
fall_over_bfd_multi_hop	Boolean	`true`, `false`	No
fall_over_bfd_single_hop	Boolean	`true`, `false`	No
fall_over_bfd_check_control_plane_failure	Boolean	`true`, `false`	No
fall_over_bfd_strict_mode	Boolean	`true`, `false`	No
fall_over_maximum_metric_route_map	String		No
disable_connected_check	Boolean	`true`, `false`	No
ttl_security_hops	Integer	min: `0`, max: `254`	No
local_as	Integer		No
local_as_no_prepend	Boolean	`true`, `false`	No
local_as_replace_as	Boolean	`true`, `false`	No
local_as_dual_as	Boolean	`true`, `false`	No
update_source_loopback	Integer		No
activate	Boolean	`true`, `false`	No
send_community	Choice	`both`, `extended`, `standard`	No
route_reflector_client	Boolean	`true`, `false`	No
soft_reconfiguration	Choice	`inbound`	No
default_originate	Boolean	`true`, `false`	No
default_originate_route_map	String		No
route_maps	List	`[route_maps]`	No
ebgp_multihop	Boolean	`true`, `false`	No
ebgp_multihop_max_hop	Integer	min: `1`, max: `255`	No
ha_mode_graceful_restart	Boolean	`true`, `false`	No
next_hop_self	Boolean	`true`, `false`	No
next_hop_self_all	Boolean	`true`, `false`	No
advertisement_interval	Integer	min: `0`, max: `600`	No

redistribute (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs)

Name	Type	Constraint	Mandatory	Default Value
connected	Boolean	`true`, `false`	No
static	Boolean	`true`, `false`	No

admin_distances (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs)

Name	Type	Constraint	Mandatory
distance	Integer	min: `1`, max: `255`	Yes
source_ip	IP		Yes
wildcard	IP		Yes
acl	String		No

networks (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast.vrfs)

Name	Type	Constraint	Mandatory
prefix	IP		Yes
route_map	String		No
backdoor	Boolean	`true`, `false`	No
evpn	Boolean	`true`, `false`	No

redistribute (iosxe.devices.configuration.routing.bgp.address_family.ipv6_unicast.vrfs)

Name	Type	Constraint	Mandatory	Default Value
connected	Boolean	`true`, `false`	No
static	Boolean	`true`, `false`	No

route_maps (iosxe.devices.configuration.routing.bgp.address_family.ipv4_unicast.vrfs.neighbors)

Name	Type	Constraint	Mandatory	Default Value
direction	Choice	`in`, `out`	Yes
name	String		Yes

Examples

Example 1: The example below shows basic BGP configuration to bring up an IPv4 Unicast Neighbor and includes basic attributes such as Password protected session, aggregate adderesses, redistribution, network advertisement and applying a route-map to the neighbor.

iosxe:
  devices:
    - name: device1
      configuration:
        routing:
          bgp:
            as_number: 65000
            default_ipv4_unicast: true
            log_neighbor_changes: true
            router_id_loopback: 0
            neighbors:
              - ip: 192.168.1.1
                remote_as: 65001
                password: 045802150C2E1D1C5A
                password_type: 7
            address_family:
              ipv4_unicast:
                redistribute_connected: true
                redistribute_static: true
                aggregate_addresses:
                  - address: 192.168.0.0
                    mask: 255.255.0.0
                  - address: 10.0.0.0
                    mask: 255.255.255.0
                networks:
                  - network: 10.0.0.0
                    mask: 255.255.255.0
                    route_map: RM1
                    backdoor: false
                  - network: 172.16.12.0
                    mask: 255.255.255.0
                  - network: 192.168.12.0
                    route_map: RM2
                    backdoor: true
                  - network: 172.16.19.0
                neighbors:
                  - ip: 192.168.1.1
                    route_maps:
                      - direction: in
                        name: RM3

Example 2: The example below shows basic BGP configuration to bring up an VRF aware IPv4 Unicast Neighbor and includes basic attributes such as Password protected session, aggregate adderesses, redistribution, network advertisement and applying a route-map to the neighbor.

iosxe:
  devices:
    - name: device1
      configuration:
        routing:
          bgp:
            as_number: 65000
            log_neighbor_changes: true
            address_family:
              ipv4_unicast:
                vrfs:
                  - vrf: MY_VRF
                    redistribute_connected: true
                    redistribute_static: false
                    aggregate_addresses:
                      - address: 192.168.17.0
                        mask: 255.255.255.0
                      - address: 192.168.18.0
                        mask: 255.255.255.0
                    networks:
                      - network: 10.0.0.0
                        mask: 255.255.255.0
                        route_map: RM1
                        backdoor: false
                      - network: 172.16.12.0
                        mask: 255.255.255.0
                      - network: 192.168.12.0
                        route_map: RM2
                        backdoor: true
                      - network: 172.16.19.0
                    neighbors:
                      - ip: 192.168.1.1
                        remote_as: 65001
                        description: "REMOTE_ROUTER"
                        shutdown: false
                        log_neighbor_changes: true
                        password_type: 7
                        password: 045802150C2E1D1C5A
                        activate: true
                        send_community: both
                        soft_reconfiguration: inbound
                        route_maps:
                          - direction: in
                            name: RM2

Example 3: The Example below is a full blank data model for IPv4 address-family of BGP - VRF and non-VRF aware.

iosxe:
  devices:
    - name: router1
      configuration:
        routing:
          bgp:
            as_number: 65001
            default_ipv4_unicast: true
            log_neighbor_changes: true
            router_id_loopback: 100
            neighbors:
              - ip: 10.0.0.1
                remote_as: 65000
                description: "router2"
                shutdown: false
                cluster_id: 2.2.2.2
                version: 4
                disable_connected_check: false
                fall_over_default_enable: false
                fall_over_default_route_map: RM1
                fall_over_bfd_multi_hop: false
                fall_over_bfd_single_hop: false
                fall_over_bfd_check_control_plane_failure: false
                fall_over_bfd_strict_mode: false
                fall_over_maximum_metric_route_map: RM2
                local_as: 65003
                local_as_no_prepend: false
                local_as_replace_as: false
                local_as_dual_as: false
                log_neighbor_changes: true
                password_type: 7
                password: 045802150C2E1D1C5A
                peer_group: PEER1
                timers_keepalive: 60
                timers_holdtime: 180
                timers_minimum_neighbor_holdtime: 30
                ttl_security_hops: 1
                update_source_loopback: 100
                ebgp_multihop: false
                ebgp_multihop_max_hop: 5
            address_family:
              ipv4_unicast:
                redistribute_connected: true
                redistribute_static: false
                aggregate_addresses:
                  - address: 192.168.0.0
                    mask: 255.255.0.0
                networks:
                  - network: 10.10.10.0
                    mask: 255.255.255.0
                    route_map: RM3
                    backdoor: false
                  - network: 192.168.0.0
                    route_map: RM4
                    backdoor: false
                neighbors:
                  - ip: 10.0.01
                    activate: true
                    send_community: both
                    route_reflector_client: false
                    soft_reconfiguration: inbound
                    default_originate: false
                    default_originate_route_map:
                    route_maps:
                      - direction: in
                        name: RM5
                vrfs:
                  - vrf:
                    redistribute_connected: true
                    redistribute_static: true
                    router_id_loopback: 200
                    aggregate_addresses:
                      - address: 172.16.0.0
                        mask: 255.255.0.0
                    networks:
                      - network: 10.10.20.0
                        mask: 255.255.0.0
                        route_map: RM6
                        backdoor: false
                      - network: 192.168.32.0
                        route_map: RM7
                        backdoor: false
                    neighbors:
                      - ip: 20.20.20.1
                        remote_as: 65003
                        description: "router3"
                        shutdown: false
                        cluster_id: 2.2.2.2
                        log_neighbor_changes: true
                        password_type: 7
                        password: 045802150C2E1D1C5A
                        timers_keepalive: 60
                        timers_holdtime: 180
                        timers_minimum_holdtime: 30
                        fall_over_default_route_map: RM8
                        fall_over_bfd_multi_hop: false
                        fall_over_bfd_single_hop: false
                        fall_over_bfd_check_control_plane_failure: false
                        fall_over_bfd_strict_mode: false
                        fall_over_maximum_metric_route_map: RM9
                        disable_connected_check: false
                        ttl_security_hops: 1
                        local_as: 65000
                        local_as_no_prepend: false
                        local_as_replace_as: false
                        local_as_dual_as: false
                        update_source_loopback: 200
                        activate: true
                        send_community: both
                        route_reflector_client: false
                        soft_reconfiguration: inbound
                        default_originate: false
                        default_originate_route_map: RM10
                        route_maps:
                          - direction: out
                            name: RM11
                        ebgp_multihop: false
                        ebgp_multihop_max_hop: 5
                        ha_mode_graceful_restart: false
                        next_hop_self: false
                        next_hop_self_all: false
                        advertisement_interval: 60