chef/cookbooks/nginx/templates/default/modules/http_realip.conf.erb

<% node['nginx']['realip']['addresses'].each do |address| -%>
set_real_ip_from <%= address %>;
<% end -%>
real_ip_header <%= node['nginx']['realip']['header'] %>;
real_ip_recursive <%= node['nginx']['realip']['real_ip_recursive'] %>;