First fully working proof-of-concept, only works on arch for now

bird-config.j2

@@ -0,0 +1,24 @@
+protocol device {
+    scan time 10;
+};
+
+protocol direct {
+    ipv4;
+    ipv6;
+    interface "dn42dummy0";
+};
+
+protocol babel int_babel {
+    randomize router id on;
+    ipv4 {
+        import all;
+        export all;
+    };
+    ipv6 {
+        import all;
+        export all;
+    };
+    interface "{% if vlan is defined %}host0.{{ vlan }}{% else %}host0{% endif %}" {
+        type wired;
+    };
+};

deploy.yml

@@ -0,0 +1,68 @@
+- hosts: all
+  remote_user: root
+  tasks:
+    - name: install debian dependencies
+      package:
+        name: nginx,bird2
+        state: present
+      when: ansible_distribution == 'Debian'
+    - name: install arch dependencies
+      pacman:
+        name: nginx,bird
+        state: present
+      when: ansible_distribution == 'Archlinux'
+    - name: see if host0 exists / if this is a systemd-nspawn container
+      stat:
+        path: /sys/class/net/host0
+      register: host0
+    - name: configure host0
+      template:
+        src: host0-network.j2
+        dest: /etc/systemd/network/10-host0.network
+    - name: configure host0 vlan .netdev
+      template:
+        src: host0-vlan-netdev.j2
+        dest: /etc/systemd/network/host0-vlan.netdev
+      when: vlan is defined
+    - name: configure host0 vlan .network
+      template:
+        src: host0-vlan-network.j2
+        dest: /etc/systemd/network/host0-vlan.network
+      when: vlan is defined
+    - name: configure dummy interface .netdev
+      template:
+        src: dn42dummy0-netdev.j2
+        dest: /etc/systemd/network/dn42dummy0.netdev
+    - name: configure dummy interface .network
+      template:
+        src: dn42dummy0-network.j2
+        dest: /etc/systemd/network/dn42dummy0.network
+    - name: add nginx config
+      template:
+        src: nginx-global.j2
+        dest: /etc/nginx/nginx.conf
+    - name: add bird config on arch
+      template:
+        src: bird-config.j2
+        dest: /etc/bird.conf
+      when: ansible_distribution == 'Archlinux'
+    - name: add bird config on debian
+      template:
+        src: bird-config.j2
+        dest: /etc/bird/bird.conf
+      when: ansible_distribution == 'Debian'
+    - name: enable and reload/start systemd-networkd
+      systemd:
+        state: reloaded
+        name: systemd-networkd.service
+        enabled: true
+    - name: enable and reload/start nginx
+      systemd:
+        state: reloaded
+        name: nginx.service
+        enabled: true
+    - name: enable and reload/start bird
+      systemd:
+        state: reloaded
+        name: bird.service
+        enabled: true

dn42dummy0-netdev.j2

@@ -0,0 +1,3 @@
+[NetDev]
+Name=dn42dummy0
+Kind=dummy

dn42dummy0-network.j2

@@ -0,0 +1,8 @@
+[Match]
+Name=dn42dummy0
+
+[Network]
+Address=fd32:6b0:70a6:8181::81/128
+{% if unicastv6 is defined %}
+Address={{ unicastv6 }}/128
+{% endif %}

dn42routes.j2

@@ -0,0 +1,22 @@
+[Route]
+Destination=10.0.0.0/8
+Gateway=_dhcp4
+Metric=1024
+
+[Route]
+Destination=172.20.0.0/14
+Gateway=_dhcp4
+Metric=1024
+
+[Route]
+Destination=172.31.0.0/16
+Gateway=_dhcp4
+Metric=1024
+
+[Route]
+Destination=fd00::/8
+Gateway=_ipv6ra
+Metric=1024
+{% if unicastv6 is defined %}
+PreferredSource={{ unicastv6 }}
+{% endif %}

host0-network.j2

@@ -0,0 +1,21 @@
+[Match]
+Name=host0
+
+[Network]
+DHCP=true
+IPv6AcceptRA=true
+LinkLocalAddressing=ipv6
+{% if vlan is defined %}
+VLAN=br0.{{ vlan }}
+{% endif %}
+
+# These route metrics have to be higher than everything else
+[DHCPv4]
+RouteMetric=2048
+
+[IPv6AcceptRA]
+RouteMetric=2048
+
+{% if vlan is undefined %}
+{% include 'dn42routes.j2' %}
+{% endif %}

host0-vlan-netdev.j2

@@ -0,0 +1,6 @@
+[NetDev]
+Name=host0.{{ vlan }}
+Kind=vlan
+
+[VLAN]
+Id={{ vlan }}

host0-vlan-network.j2

@@ -0,0 +1,17 @@
+[Match]
+Name=host0.{{ vlan }}
+
+[Network]
+DHCP=true
+IPv6AcceptRA=true
+
+[DHCPv4]
+RouteMetric=1024
+UseRoutes=false
+UseGateway=false
+
+[IPv6AcceptRA]
+UseGateway=false
+UseRoutePrefix=false
+
+{% include 'dn42routes.j2' %}

inventory.yml

@@ -0,0 +1,6 @@
+all:
+  hosts:
+    us1.myip.9pfs.dn42:
+      ansible_host: fd32:6b0:70a6:8181::1
+      unicastv6: fd32:6b0:70a6:8181::1
+      fqdn: us1.myip.9pfs.dn42

nginx-global.j2

@@ -0,0 +1,11 @@
+worker_processes 1;
+
+events {
+	worker_connections 1024;
+}
+
+http {
+	sendfile on;
+	keepalive_timeout 65;
+{% include 'nginx-site.j2' %}
+}

nginx-site.j2

@@ -1,14 +1,14 @@
 server {
 	listen [fd32:6b0:70a6:8181::81]:80;
-	{% if unicastv6 is defined %}
+{% if unicastv6 is defined %}
 	listen [{{ unicastv6 }}]:80;
-    {% endif %}
+{% endif %}
 	server_name myip.9pfs.dn42;
 	server_name *.myip.9pfs.dn42;
 	server_name [fd32:6b0:70a6:8181::81];
-    {% if unicastv6 is defined %}
+{% if unicastv6 is defined %}
-	listen [{{ unicastv6 }}];
+	server_name [{{ unicastv6 }}];
-	{% endif %}
+{% endif %}
 
 	location = /raw {
 		return 200 '$remote_addr\n';
@@ -18,7 +18,7 @@ server {
 	location = /api {
 		default_type application/json;
 		add_header 'Access-Control-Allow-Origin' '*';
-		return 200 '{\n\t"version": "1.0",\n\t"ip": "$remote_addr",\n\t"server": "$server_addr",\n\t"node_as": "4242422002",\n\t"node_location": "{% if country is defined %}{{ country }}{% else %}US{% endif %},\n\t"node_id": "{% if fqdn is defined %}{{ fqdn }}{% else %}myip.9pfs.dn42{% endif %}"\n}';
+		return 200 '{\n\t"version": "1.0",\n\t"ip": "$remote_addr",\n\t"server": "$server_addr",\n\t"node_as": "4242422002",\n\t"node_location": "{% if country is defined %}{{ country }}{% else %}US{% endif %}",\n\t"node_id": "{% if fqdn is defined %}{{ fqdn }}{% else %}myip.9pfs.dn42{% endif %}"\n}';
 	}
 	location = / {
 		{% include 'nginx-html.j2' %}