.htaccess IP allows and denies are not working in Nginx with Reverse Proxy (ea-nginx)

Symptoms

You may find that .htaccess allows and denies for IPs work under Apache but not under Nginx with Reverse Proxy (ea-nginx).

Description 

This may be due to mod_remoteip not being set up for Apache, causing all proxied connections to appear to be coming from the server's own IP.

Workaround

Apache will need mod_remoteip installed and configured to properly translate the visitor IP from the Nginx proxy header. The article below covers how to enable mod_remoteip. Note that Nginx uses the X-Forwarded-For header.

How to enable mod_remoteip