add contrib

contrib/dhcpd6.conf.erb

@@ -0,0 +1,13 @@
+option dhcp6.name-servers <%= ', '.join(@dns_resolvers_ipv6) %>;
+option dhcp6.sntp-servers <%= ', '.join(@ntp_servers_ipv6) %>;
+
+# specify API server URL (RFC8910)
+option dhcp6.v6-captive-portal "https://<%= @service_name %>/api/captive-portal";
+
+# The delay before information-request refresh
+#  (minimum is 10 minutes, maximum one day, default is to not refresh)
+#  (set to 6 hours)
+option dhcp6.info-refresh-time 3600;
+
+subnet6 <%= @client_ipv6 %> {
+}