Using Peering Manager for Automated Configuration on VyOS

Wieger Bontekoe

Sep 26, 2024 • 5 min read

Peering Manager is an open-source BGP session management solution including Peeringdb synchronization for automating session management. Peering Manager is able to automatically generate the BGP configuration for various vendors, however VyOS was not yet documented.

I created the template below as an example to automatically generate the sessions for VyOS, with some additions when it comes to the route maps. Based on Tags I determine where a peer is located (at least where their equipment is located) compared to our own equipment. It happens when you are active on multiple internet exchanges that your peer (for example Cloudflare) is present at one internet exchange in the same city, while at the other exchange they are 'remote'. In order to maintain the lowest latency I want to influence the local preference based on this information.

To use cloudflare as an example I created the peer (enabled) and added a tag to it (Peer source: Amsterdam, slug: peer-source-amsterdam). The slug is important for the template so pay attention to it.

With the second session, which is physically at a different location, I do the same (tag: peer source Frankfurt, slug peer-source-frankfurt).

In the template I defined multiple locations where the peers can be found and I link a local-pref to this. Based on the tags I match these and a route-map comes out with the various peers that match on IP and that are then assigned a correct local-pref.

{%- set local_pref_map = {
'frankfurt': 200,
'amsterdam': 125,
'prague': 125,
'berlin': 125,
'default': 100
} -%}
{%- set cities = ['frankfurt', 'amsterdam', 'prague', 'berlin'] -%}
{%- set tags = ['peer-source-frankfurt', 'peer-source-amsterdam', 'peer-source-prague', 'peer-source-berlin'] -%}
{%- set asns = { 'frankfurt': [], 'amsterdam': [], 'prague': [], 'berlin': [] } -%}
{%- set sessions = { 'frankfurt': [], 'amsterdam': [], 'prague': [], 'berlin': [] } -%}
{%- for as in autonomous_systems -%}
{%- for tag in as.tags.all() -%}
{%- if tag.slug in tags and as.prefixes -%}
{%- set city = tag.slug.split('-')[-1] -%}
{%- if city in asns -%}
{%- set _ = asns[city].append(as) -%}
{%- endif -%}
{%- endif -%}
{%- endfor -%}
{%- endfor -%}

{%- for city in cities -%}
{%- set rule_start = 10 -%}
{%- for as in asns[city] -%}
set policy as-path-list PEERS-{{ city | upper }} rule {{ rule_start + loop.index0 }} action permit
set policy as-path-list PEERS-{{ city | upper }} rule {{ rule_start + loop.index0 }} description "Peer {{ as.name }} |{{ city | capitalize }}"
set policy as-path-list PEERS-{{ city | upper }} rule {{ rule_start + loop.index0 }} regex "200249 {{ as.asn }}"
{% endfor %}
{%- endfor -%}
{%- for internet_exchange in internet_exchange_points -%}
{%- for session in internet_exchange | sessions -%}
{%- for tag in session.tags.all() -%}
{%- set city = tag.slug.split('-')[-1] -%}
{%- if city in sessions -%}
{%- set _ = sessions[city].append(session) -%}
{%- endif -%}
{%- endfor -%}
{%- endfor -%}
{%- endfor -%}


{%- for city in cities -%}
{%- set slug_value = 'peers-' ~ city -%}
{%- set community = communities.filter(slug=slug_value).first() -%}
{%- if community is not none -%}
{%- set community_values = community.value.split(',') -%}
{%- endif -%}
{%- set rule_start = 10 -%}
set policy route-map PEERS-{{ city | upper }}-v6 rule {{ rule_start + loop.index0 }} action permit
set policy route-map PEERS-{{ city | upper }}-v6 rule {{ rule_start + loop.index0 }} set local-preference {{ local_pref_map.get(location, local_pref_map[city]) }}
{%- set rule_counter = rule_start + loop.index0 -%}
{% for community in community_values %}
set policy route-map PEERS-{{ city | upper }}-v6 rule {{ rule_counter }} set large-community add {{ community }}
{%- endfor %}
set policy route-map PEERS-{{ city | upper }}-v6 rule {{ rule_start + loop.index0 }} set large-community add 200249:100:{{ local_pref_map.get(location, local_pref_map[city]) }}
{% endfor -%}

{%- for city in cities -%}
{%- set slug_value = 'peers-' ~ city -%}
{%- set community = communities.filter(slug=slug_value).first() -%}
{%- if community is not none -%}
{%- set community_values = community.value.split(',') -%}
{%- endif -%}
{%- set rule_start = 10 -%}
set policy route-map PEERS-{{ city | upper }}-v4 rule {{ rule_start + loop.index0 }} action permit
set policy route-map PEERS-{{ city | upper }}-v4 rule {{ rule_start + loop.index0 }} set local-preference {{ local_pref_map.get(location, local_pref_map[city]) }}
{%- set rule_counter = rule_start + loop.index0 -%}
{% for community in community_values %}
set policy route-map PEERS-{{ city | upper }}-v4 rule {{ rule_counter }} set large-community add {{ community }}
{%- endfor %}
set policy route-map PEERS-{{ city | upper }}-v4 rule {{ rule_start + loop.index0 }} set large-community add 200249:100:{{local_pref_map.get(location, local_pref_map[city]) }}
{% endfor %}
{%- set rule_start = namespace(c = 10) -%}
{%- set v4_count = namespace(c = 0) -%}
{%- set v6_count = namespace(c = 0) -%}
{%- for city in cities -%}
{%- for session in sessions[city] -%}
{%- if session | ip_version == 4 -%}
set policy route-map eBGP-import-v4 rule {{ rule_start.c + v4_count.c }} action permit
set policy route-map eBGP-import-v4 rule {{ rule_start.c + v4_count.c }} description '{{ session.autonomous_system.name |
safe_string }} | {{ city | capitalize }}'
set policy route-map eBGP-import-v4 rule {{ rule_start.c + v4_count.c }} match peer {{ session | ip }}
set policy route-map eBGP-import-v4 rule {{ rule_start.c + v4_count.c }} call PEERS-{{ city | upper }}-v4
{% set v4_count.c = v4_count.c + 1 %}
{%- endif -%}
{%- endfor -%}
{%- endfor -%}
set policy route-map eBGP-import-v4 rule 999 action permit
set policy route-map eBGP-import-v4 rule 999 description 'Set default local-pref'
set policy route-map eBGP-import-v4 rule 999 set local-preference 100
{% set rule_start = namespace(c = 10) -%}
{%- set v4_count = namespace(c = 0) -%}
{%- set v6_count = namespace(c = 0) -%}
{%- for city in cities -%}
{%- for session in sessions[city] -%}
{%- if session | ip_version == 6 -%}
set policy route-map eBGP-import-v6 rule {{ rule_start.c + v6_count.c }} action permit
set policy route-map eBGP-import-v6 rule {{ rule_start.c + v6_count.c }} description '{{ session.autonomous_system.name
|
safe_string }} | {{ city | capitalize }}'
set policy route-map eBGP-import-v6 rule {{ rule_start.c + v6_count.c }} match peer {{ session | ip }}
set policy route-map eBGP-import-v6 rule {{ rule_start.c + v6_count.c }} call PEERS-{{ city | upper }}-v6
{% set v6_count.c = v6_count.c + 1 %}
{%- endif -%}
{%- endfor -%}
{%- endfor -%}
set policy route-map eBGP-import-v6 rule 999 action permit
set policy route-map eBGP-import-v6 rule 999 description 'Set default local-pref'
set policy route-map eBGP-import-v6 rule 999 set local-preference 100


{% for internet_exchange in internet_exchange_points -%}
{%- for family in (6, 4) -%}
set protocols bgp peer-group ixp-{{ internet_exchange.slug }}-v{{ family }} local-as 200249
set protocols bgp peer-group ixp-{{ internet_exchange.slug }}-v{{ family }} description "IXP {{ internet_exchange.name }}"
set protocols bgp peer-group ixp-{{ internet_exchange.slug }}-v{{ family }} address-family ipv{{ family }}-unicast remove-private-as
{%- if internet_exchange | merge_import_policies %}
set protocols bgp peer-group ixp-{{ internet_exchange.slug }}-v{{ family }} address-family ipv{{ family }}-unicast route-map import {{ internet_exchange | iter_import_policies(family=family, field='slug') | join(' ') }}
{%- endif %}
{%- if internet_exchange | merge_export_policies %}
set protocols bgp peer-group ixp-{{ internet_exchange.slug }}-v{{ family }} address-family ipv{{ family }}-unicast route-map export {{ internet_exchange | iter_export_policies(family=family, field='slug') | join(' ') }}
{% endif -%}
{%-  endfor -%}
{%- for session in internet_exchange | sessions -%}
{%- if session.enabled or session.provisioning and not session.is_route_server %}
set protocols bgp neighbor {{ session | ip }} peer-group ixp-{{ internet_exchange.slug }}-v{{ session | ip_version}}
set protocols bgp neighbor {{ session | ip }} remote-as {{ session.autonomous_system.asn }}
set protocols bgp neighbor {{ session | ip }} description "AS{{ session.autonomous_system.asn }}:{{ session.autonomous_system.name | safe_string }}"
{%- if session | max_prefix %}
set protocols bgp neighbor {{ session | ip }} address-family ipv{{ session | ip_version }}-unicast maximum-prefix {{session | max_prefix }}
{%- endif %}
{%- endif -%}
{%- endfor -%}
{% endfor %}
{%- for group in bgp_groups %}
    {%- for family in (6, 4) %}
set protocols bgp peer-group {{ group.name }}-v{{ family }} local-as 200249

{%- if group | iter_import_policies %}
set protocols bgp peer-group {{ group.name }}-v{{ family }} address-family ipv{{ family }}-unicast route-map import {{
group | iter_import_policies(family=family, field='slug') | join(' ') }}
{%- endif %}
{%- if group | iter_export_policies %}
set protocols bgp peer-group {{ group.name }}-v{{ family }} address-family ipv{{ family }}-unicast route-map export {{
group | iter_export_policies(family=family, field='slug') | join(' ') }}
{%- endif %}
set protocols bgp peer-group {{ group.name }}-v{{ family }} address-family ipv{{ family }}-unicast soft-reconfiguration inbound
set protocols bgp peer-group {{ group.name }}-v{{ family }} address-family ipv{{ family }}-unicast remove-private-as

{%- for session in router | direct_sessions(family=family, group=group) -%}
set protocols bgp neighbor {{ session | ip }} peer-group {{ group.name }}-v{{ family }}
set protocols bgp neighbor {{ session | ip }} description "Transit: AS{{ session.autonomous_system.asn }} - {{ session.autonomous_system.name }}"
{%- endfor %}
    {%- endfor %}
{%- endfor %}

After generating the config we have:

Route maps based on the cities (PEERS-FRANKFURT, PEERS-Amsterdam
An import route map that matches on peer address and links to the respective route map of the city
All BGP sessions configured in a peer group
Any direct BGP sessions configured in a peer group

Small note;
The napalm module for Vyos is outdated and does not work out of the box. You can use my fork for this, with this pinging and polling of the router and sessions does work.