Debian, Ubuntu

How to get the real IP address using CloudFlare and nginx on CentOS / Debian / Ubuntu

In this tutorial we will be configuring Cloudflare real ip under nginx server. As a result Cloudflare service will helps protect and speed up your web site project. In a standard shared hosting plan, visitors access the site directly.

Now we will start with the simplest configuration for enabling Cloudflare real ip.

Ensure you’ve nginx real ip module installed you can verify via this command:

nginx -V 2>&1 | grep -o with-http_realip_module

It will output:

with-http_realip_module

that means real ip module is already installed and if you get blank output then you need to install it, for CentOS, Debian, Ubuntu it is already installed by default.

To enable clouflare real ip config navigate to /etc/nginx/ and edit the nginx.conf file:

nano /etc/nginx/nginx.conf

and add this config under http { (before } ):

    # Cloudflare Real IP Nginx
    set_real_ip_from   103.21.244.0/22;
    set_real_ip_from   103.22.200.0/22;
    set_real_ip_from   103.31.4.0/22;
    set_real_ip_from   104.16.0.0/12;
    set_real_ip_from   108.162.192.0/18;
    set_real_ip_from   131.0.72.0/22;
    set_real_ip_from   141.101.64.0/18;
    set_real_ip_from   162.158.0.0/15;
    set_real_ip_from   172.64.0.0/13;
    set_real_ip_from   173.245.48.0/20;
    set_real_ip_from   188.114.96.0/20;
    set_real_ip_from   190.93.240.0/20;
    set_real_ip_from   197.234.240.0/22;
    set_real_ip_from   198.41.128.0/17;
    set_real_ip_from   2400:cb00::/32;
    set_real_ip_from   2606:4700::/32;
    set_real_ip_from   2803:f800::/32;
    set_real_ip_from   2405:b500::/32;
    set_real_ip_from   2405:8100::/32;
    set_real_ip_from   2c0f:f248::/32;
    set_real_ip_from   2a06:98c0::/29;
    real_ip_header     CF-Connecting-IP;

and restart nginx service:

systemctl restart nginx

example nginx config with cloudflare real ip config:

# For more information on configuration, see:
#   * Official English Documentation: http://nginx.org/en/docs/
#   * Official Russian Documentation: http://nginx.org/ru/docs/

user nginx;
worker_processes auto;
error_log /var/log/nginx/error.log;
pid /run/nginx.pid;

# Load dynamic modules. See /usr/share/nginx/README.dynamic.
include /usr/share/nginx/modules/*.conf;

events {
    worker_connections 1024;
}

http {
    log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    access_log  /var/log/nginx/access.log  main;

    # don't send the nginx version number in error pages and Server header
    server_tokens off;

    sendfile            on;
    tcp_nopush          on;
    tcp_nodelay         on;
    keepalive_timeout   65;
    types_hash_max_size 2048;

    include             /etc/nginx/mime.types;
    default_type        application/octet-stream;

    # Load modular configuration files from the /etc/nginx/conf.d directory.
    # See http://nginx.org/en/docs/ngx_core_module.html#include
    # for more information.
    include /etc/nginx/conf.d/*.conf;

    include /etc/nginx/sites-enabled/*;

    server {
        listen       80 default_server;
        listen       [::]:80 default_server;
        server_name  _;
        root         /usr/share/nginx/html;

        # Load configuration files for the default server block.
        include /etc/nginx/default.d/*.conf;

        location / {
        }

        error_page 404 /404.html;
            location = /40x.html {
        }

        error_page 500 502 503 504 /50x.html;
            location = /50x.html {
        }
    }

    # Cloudflare Real IP Nginx
    set_real_ip_from   103.21.244.0/22;
    set_real_ip_from   103.22.200.0/22;
    set_real_ip_from   103.31.4.0/22;
    set_real_ip_from   104.16.0.0/12;
    set_real_ip_from   108.162.192.0/18;
    set_real_ip_from   131.0.72.0/22;
    set_real_ip_from   141.101.64.0/18;
    set_real_ip_from   162.158.0.0/15;
    set_real_ip_from   172.64.0.0/13;
    set_real_ip_from   173.245.48.0/20;
    set_real_ip_from   188.114.96.0/20;
    set_real_ip_from   190.93.240.0/20;
    set_real_ip_from   197.234.240.0/22;
    set_real_ip_from   198.41.128.0/17;
    set_real_ip_from   2400:cb00::/32;
    set_real_ip_from   2606:4700::/32;
    set_real_ip_from   2803:f800::/32;
    set_real_ip_from   2405:b500::/32;
    set_real_ip_from   2405:8100::/32;
    set_real_ip_from   2c0f:f248::/32;
    set_real_ip_from   2a06:98c0::/29;
    real_ip_header     CF-Connecting-IP;
}