I had an annoyance where varnish proxy infront of a LAMP server and the LAMP server therefore thought all clients were from the varnish proxy – rather than the client’s real IP address – i.e. $_SERVER['REMOTE_ADDR'] was set to the IP address of the Varnish proxy and not that of the client’s actual IP address.
Obviously, Varnish adds the X_HTTP_FORWARDED_FOR HTTP header in when a connection comes through it; so my initial thought was to just overwrite PHP’s $_SERVER['REMOTE_ADDR'] setting. A bit of a hack and annoying – as I’d need to fix all sites, or have some sort of global prepend file (which is horrible).
I then discovered something which sorts the problem out - RPAF
- apt-get install libapache2-mod-rpaf
- Edit /etc/apache2/mods-enabled/rpaf.conf and ensure your proxy server’s IP address is listed on the RPAFproxy_ips line (e.g. RPAFproxy_ips 127.0.0.1 89.16.176.x).
- Restart Apache, and you’ll then find that the $_SERVER['REMOTE_ADDR'] value will be correct.