mod_rpaf is an apache module that translate proxy IP to real IP when apache web server is behind a proxy server.
https://github.com/gnif/mod_rpaf/
To install on Ubuntu, run
apt install -y libapache2-mod-rpaf
Config file available at
root@vps528168:~# cat /etc/apache2/mods-enabled/rpaf.conf
RPAFenable On
# When enabled, take the incoming X-Host header and
# update the virtualhost settings accordingly:
RPAFsethostname On
# Define which IP's are your frontend proxies that sends
# the correct X-Forwarded-For headers:
RPAFproxy_ips 127.0.0.1 ::1 193.70.86.5
# Change the header name to parse from the default
# X-Forwarded-For to something of your choice:
RPAFheader X-Real-IP
root@vps528168:~#