Comment by izacus
6 days ago
"The shit about IPv4" was easy to learn and well documented and supported.
"The shit about IPv6" is a mess of approaches that even the biggest fanboys can't agree on and are even less available on equipment used by people in prod.
IPv6 has failed wide adoption in 30 decades, calling it "easy" is outright denying the reality and shows the utter dumb obliviousness of people trying to push it and failing to realize where the issues are.
Could you share a list of IPv6 issues that IPv4 does not exhibit? Something that becomes materially harder with IPv6? E.g., "IPv6 addresses are long and unwieldy, hard to write down or remember". What else?
Traffic shapping in v6 is harder than v4. At least it was for me, because NDP messages were going into the shaping queue, but then getting lost since the queue only had a 128 bit address field, and 128 bits isn't actually enough for local addresses. When the traffic shaping allowed traffic immediately, the NDP traffic would be sent, but if it needed to be queued, the adapter index would get lost (or something) and the packets disappeared. So I'd get little bursts of v6 until NDP entries timed out and small queues meant a long time before it would work again.
Not an issue in ipv4 because ARP isn't IPv4 so IP traffic shaping ignores it automatically.
Software support is a big one. I ran pfSense. It did not support changing IPv6 prefixes. It still barely does. So something as simple has having reliable IPv6 connectivity and firewall rules with pfSense was impossible just a few years ago for me.
Android doesn't support DHCPv6 so I can't tell it my preferred NTP server, and Android silently ignores your local DNS server if it is advertised with a IPv4 address and the Android device got a IPv6 address.
Without DHCPv6 then dynamic DNS is required for all servers. Even a 56 bit prefix is too much to remember, especially when it changes every week. So then you need to install and configure a dynamic DNS client on all servers in your network.