To enable GeoIP module on nginx, first install geoIP module. This you can install it with your system package manager or download from maxmind.

GeoLite Legacy Downloadable Databases

On Ubuntu 16.04, i installed GeoIP with command

apt install geoip-database-contrib

Now edit nginx.conf

vi /etc/nginx/nginx.conf

Find

http {

Add below

geoip_country /usr/share/GeoIP/GeoIP.dat;
geoip_city /usr/share/GeoIP/GeoLiteCity.dat;

Now test nginx config with command

nginx -t

Restart nginx with

nginx -s reload

At this stage, you can use geoip codes in your nginx virtual host entry.

Lets test it by editing default virtual host entry

vi /etc/nginx/sites-enabled/default 

Add inside

location /geoip/ {
    return 200 $geoip_country_code;
}

Now access the URL, you will see your country code.

$ curl http://lab.hosthat.com:8080/geoip/
FR$ 

Passing GeoIP Variables to PHP

Edit /etc/nginx/fastcgi_params

vi /etc/nginx/fastcgi_params 

Add

fastcgi_param GEOIP_COUNTRY_CODE        $geoip_country_code;

Redirecting Traffic Based on Country Code

In virtual host entry, add

if ($geoip_country_code ~ "A1") {
    rewrite ^/(.*)$ http://a1.hostonnet.com/ redirect;
}

if ($geoip_country_code ~ "RU") {
    rewrite ^/(.*)$ http://ru.hostonnet.com/ redirect;
}

if ($geoip_country_code ~ "CN") {
    rewrite ^/(.*)$ http://cn.hostonnet.com/ redirect;
}

Nginx Echo Module

On Ubuntu/Debian, extra modules can be installed with

apt-get install nginx-extras

Now you will be able to use “echo” command directly from nginx config. Add following to nginx default virtual host

location ^~ /geoip/ {
    add_header Content-Type text/plan;
    echo 'Your are from country $geoip_country_code\n';
}

echo command is useful for debugging.

See Nginx