The script you are about to install looks for your MaxMind license information in /etc/nf, so you need to install the Geolocation system first, see Installing Geolocation. If you've installed the GeoLite2 database from Maxmind to assist with identifying countries with nftfwls, then with some little work you can access their country database and also have your system refresh it once a week. The downside of this is that you have to download the file by hand, but it's easy to use as a starter. The IPv6 file contains all the IPv4 addresses, and nftfw's reader will convert the addresses into the correct format. Place the file in blacknets.d, remembering to add. The file will be downloaded to your machine. There are three drop-down menus: choose the country, select IPv6, and CIDR and click DOWNLOAD. Visit their page Block Visitors by Country Using Firewall and scroll to the bottom of the page for the form. They offer a free download of IP addresses per country in several formats aimed at different applications. This company, based in the Isle of Man, has been collating IP addresses for many years. There are several sources for lists of networks by country, I've used two. See Wikipedia if you need more information on CIDR. To use blacknets, you need a file or files containing IP networks, one per line, using 'CIDR' notation. If you want to use this system, check that the version of nftfw you have installed is configured to support it, see How to check nftfw supports_blacknets at bottom of this page. You will want to get hold of lists of IP addresses if you want to use the blacknets feature of nftfw (v0.7.0 or later) to block access from certain countries or IP address ranges.