I've got nginx configured to do SSL termination for an apache webserver. It seems to be working, however all requests going to the webserver appear to be coming from the nginx server and not the original ip address. Is it possible for those to come through intact?
Sure it's possible.
Just install mod_rpaf. Configure apache as follows:
Where RPAFproxy_ips are the IP address(es) of your nginx reverse proxy.
Nginx needs to be configured to set the