Want to have a quick way to drop Android phones from your network?
iptables -I FORWARD -d 216.58.192.0/19 -j DROP iptables -I FORWARD -d 172.217.0.0/16 -j DROP
Not sure which network does it, but if you add this to your firewall,
the Android phones will show "Connected, no internet".
They will "connect" to the network, but not have internet access (apart from the cell
network) as a fall-back route.
They (Google) must be using some connectivity to some host or hosts in those networks?
Silly, but I suppose they had some reason to do that.
It does make it hard to trust the basics of networking when that is true, as
I would sometimes use my phone to troubleshoot networking issues.
Makes it easy for the pinks I suppose.
p.s. This works today (2019/5/28) on all current 'Droid software that I am aware of.
It might not work after they patch it. Also, assume burgerland isp's in use.