Q: How much does Maxmind's database cost?
A: The GeoLite2 database is free to download and use.
Q: How often is the IP address data updated?
A: The GeoLite2 database is updated by Maxmind weekly, and so we have a Cron task which downloads it weekly.
Q: Can I use this addon to block access to content or my entire website?
A: No. IP addresses are only checked for blocking purposes at the point of registration.
If you need to block access to visitors who are not members, you are best to use a local GeoIP database and do these checks at a web server level, rather than an application level. Using an online web service for this purpose would be prohibitively expensive.
Cloudflare also offers a service which can achieve this.
Q: What end-user information is sent to Maxmind?
None. The database is downloaded over HTTP, so the IP address of your server will be sent - but from that point, all processing occurs on your local server and no end-user information is ever sent to Maxmind.
Q: What end-user information is stored based on information returned from Maxmind?
The only data stored from Maxmind is the two-character ISO country code, and the associated country name associated with an IP address.
Q: Is it possible to check and block VPN registrations with this addon?
No - Maxmind's free GeoLite2 database does not contain VPN or other anonymous address information. I have a commercial addon in development which will provide this functionality using Maxmind's (paid) Precision Insights Web Service