feat(bootstrap): accept extra_addresses on network interfaces

roles/configuration/templates/network.j2

@@ -19,6 +19,9 @@ interface-name=en*;eth*;
 {% set search_list = configuration_dns_search %}
 {% if iface.ip | default('') | string | length %}
 address1={{ iface.ip }}/{{ iface.prefix }}{{ (',' ~ iface.gateway) if (iface.gateway | default('') | string | length) else '' }}
+{% for address in iface.extra_addresses | default([]) %}
+address{{ loop.index + 1 }}={{ address }}
+{% endfor %}
 method=manual
 {% else %}
 method=auto

roles/configuration/templates/network_eni.j2

@@ -16,6 +16,11 @@ iface {{ ifname }} inet static
 {% if loop.index0 == 0 and configuration_dns_search %}
     dns-search {{ configuration_dns_search | join(' ') }}
 {% endif %}
+{# One stanza per extra address: classic ifupdown takes one address per stanza, ifupdown2 merges them. #}
+{% for address in iface.extra_addresses | default([]) %}
+iface {{ ifname }} inet static
+    address {{ address }}
+{% endfor %}
 {% else %}
 iface {{ ifname }} inet dhcp
 {% endif %}

roles/configuration/templates/network_netplan.j2

@@ -9,6 +9,9 @@ network:
 {% if iface.ip | default('') | string | length %}
       addresses:
         - {{ iface.ip }}/{{ iface.prefix }}
+{% for address in iface.extra_addresses | default([]) %}
+        - {{ address }}
+{% endfor %}
 {% if iface.gateway | default('') | string | length %}
       routes:
         - to: default

roles/configuration/templates/network_networkd.j2

@@ -11,6 +11,9 @@ Type=ether
 [Network]
 {% if iface.ip | default('') | string | length %}
 Address={{ iface.ip }}/{{ iface.prefix }}
+{% for address in iface.extra_addresses | default([]) %}
+Address={{ address }}
+{% endfor %}
 {% if iface.gateway | default('') | string | length %}
 Gateway={{ iface.gateway }}
 {% endif %}