Very, very cool function to have. I wonder how feasible it’d be to dynamically update it using GPS measurements for fleet tracking, given even Cloudflare had to patch in support.
Don't get me wrong, I'm keenly aware there's easier ways to accomplish such a goal, but that's not the point. I have discovered something new and, as a way of practicing multiple other skills at the same time, am musing over homelab projects I could do to put it into practice and cement that knowledge.
It's just like my internal-only emoji DNS resolver: goofy, amusing, and ultimately impractical outside of the homelab, but still a great way to learn several new things together.
During 2024 Summer Olympics my then employer which DNS and core network I was still managing as I returned summer holiday. I was told by helpdesk our users around different locations at campus were not able to open national TV broadcaster streaming services and view the games.
I found out by asking few of these users that they got denied claiming to be from UK and that streaming services were not allowed abroad. TV broadcaster told me once I got someone to know anything about the matter reply, that they use MaxMind GeoIP service. So I went to see and test few addresses from MaxMind debug page and that clearly showed many addresses from around 20 subnets of /16 our IPv4 CIDR block were showing the same.
So I sent email to MaxMind support asking why and tried to find out means they use to check where each network is located and populate it to their GeoIP DB, which then clients either mirror or use remotely from their service.
After few emails with their support that they did not use RIPE (RIR) database at all as RIPE terms of use doesn't allow using RIR information for commercial purposes. So MaxMind neither did not apparently use WHOIS (RDAP) LOC records, and wrong information did not update from our LOC records DNS had either.
I never got any explanation how they figure out where that IP or CIDR block is being used. Between the lines I was assuming it's perhaps some kind of trade secret they don't like to talk about. Maybe it's using mobile devices location service or like, but amount these days VPN's are being used that could lead them updating bogus information to database service use they then sell and naive customers trust <eh>.
But most I was surprised by that how easy it was update information, basically just communicating clearly and writing polite convincing message they seemed to take that information pretty much by face value and that I was sending my messages from DNS SOA RNAME address.
But if GeoIP data provicers don't use that then who or what services do, that I still have no idea.
It was basically an MPLS traceroute tool that used LOC records on RFC1918 loopbacks to plot pretty maps (well, the lines were way too straight on long range links, but ...).
It was used by marketing and basically nobody else, but it existed !