sonic-buildimage/dockers/docker-fpm-frr/frr/bgpd/bgpd.spine_chassis_frontend_router.conf.j2

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{# VNET BGP Instance #}
! Vnet BGP instance
{% set interfaces_in_vnets = [] %}
{% block vnet_bgp_instance %}
{%  for vnet_name, vnet_metadata in VNET.items() %}
router bgp {{ DEVICE_METADATA['localhost']['bgp_asn'] }} vrf {{ vnet_name }}
  no bgp default ipv4-unicast
  bgp log-neighbor-changes
  bgp bestpath as-path multipath-relax
  no bgp default ipv4-unicast
  bgp graceful-restart restart-time 240
  bgp graceful-restart
{# Router ID #}
{%   for (name, prefix) in LOOPBACK_INTERFACE | pfx_filter %}
{%    if prefix | ipv4 and name == 'Loopback0' %}
  bgp router-id {{ prefix | ip }}
{%    endif %}
{%   endfor %}
{# Got interfaces that belong this vnet #}
{%   set interfaces_in_vnet = [] %}
{%   for (key, metadata) in INTERFACE.items() %}
{%    if "vnet_name" in metadata and metadata["vnet_name"] == vnet_name %}
{%     for (name_prefix_pair, metadata) in INTERFACE.items() %}
{%      if key == name_prefix_pair[0] %}
{%       if interfaces_in_vnet.append( name_prefix_pair[1] | ip ) %}
{%       endif %}
{%       if interfaces_in_vnets.append( name_prefix_pair[1] | ip ) %}
{%       endif %}
{%      endif %}
{%     endfor %}
{%    endif %}
{%   endfor %}
{# Each bgp neighbors #}
{%   for neighbor_addr, bgp_session in BGP_NEIGHBOR.items() %}
{%    if "local_addr" in bgp_session and bgp_session["local_addr"] in interfaces_in_vnet %}
{%     if bgp_session['asn'] | int != 0 %}
  neighbor {{ neighbor_addr }} remote-as {{ bgp_session['asn'] }}
  neighbor {{ neighbor_addr }} description {{ bgp_session['name'] }}
{# set the bgp neighbor timers if they have not default values #}
{%      if (bgp_session['keepalive'] is defined and bgp_session['keepalive'] | int != 60)
        or (bgp_session['holdtime'] is defined  and bgp_session['holdtime']  | int != 180) %}
  neighbor {{ neighbor_addr }} timers {{ bgp_session['keepalive'] }} {{ bgp_session['holdtime'] }}
{%      endif %}
{%      if 'admin_status' in bgp_session and bgp_session['admin_status'] == 'down' or 'admin_status' not in bgp_session and 'default_bgp_status' in DEVICE_METADATA['localhost'] and DEVICE_METADATA['localhost']['default_bgp_status'] == 'down' %}
  neighbor {{ neighbor_addr }} shutdown
{%      endif %}
{%      if neighbor_addr | ipv4 %}
  address-family ipv4 unicast
    neighbor {{ neighbor_addr }} activate
    neighbor {{ neighbor_addr }} soft-reconfiguration inbound
    maximum-paths 64
  exit-address-family
{%      endif %}
  address-family l2vpn evpn
    advertise ipv4 unicast
  exit-address-family
{%     endif %}
{%    endif %}
{%   endfor %}
{%  endfor %}
{% endblock vnet_bgp_instance %}
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