Comment by umanwizard
5 days ago
> We are talking about being issued only IPv6 addresses where you actually use it to connect to stuff.
You seem to be asserting that dual-stack machines use IPv4 by default, but that's not really true. If your machine has both IPv4 and IPv6 connectivity, browsers will in fact use IPv6 to connect to sites that support it, like Google. They prefer IPv6 by default and fall back to IPv4 if IPv6 is slower (Happy Eyeballs algorithm).
Of course, random software can mostly use whichever it wants, so I'm not claiming every process on such a machine will use IPv6, but most common stuff does.
In my use of Wireshark to check this, every device and software I have tested uses IPv4 by default expect mobile devices on 4g/5g networks.
Not saying its like that everywhere, but Im not seeing IPv6 default usage on dual stack systems in my experience.
Make sure they actually have GUA addresses, not just link-locals.
If you're on a Linux machine, check `ip -c addr show` for an address that's "scope global" and doesn't start with "f". Those are the ones you need. If you have one of those, check `getent ahosts google.com` to see if v6 is being sorted before v4 in DNS lookups, and then `wget google.com` to see if wget prints any errors connecting to the v6 address.
If you have GUA addresses and nothing is outright broken, devices and software that support v6 will prefer it over v6.
Well, I am. MacBook on a home internet connection in Arizona. Using IPv6 by default without me having ever had to do anything special to configure it.
You are simply misinformed. Either your setup doesn’t actually support IPv6 (or it’s much slower than IPv4 due to something being misconfigured), or you turned it off at some point, or you’re making a mistake in how you measure it. Because IPv6 is used by default on systems that support it. You don’t have to take my word for this, you can google it or ask someone else to try it.