It works behind a proxy. I have Varnish installed. Works great.
The problem might be that Apache is seeing the internal (load balancer) IP as the external IP. Your host should have a code so that X-Forward = real ip. I think their is a apache module called mod-rpaf. That might fix it.
http://www.stderr.net/apache/rpaf/
I have seen code that you can place in the wp-config.php and a wp-plugin.
https://www.openshift.com/forums/openshift/how-to-fix-incorrect-client-ip-in-wordpress-behind-proxy
Maybe I am over thinking?