I think you’re conflating multiple things there. There’s nothing magical about IPv4 that gives your LAN addresses stability when your ISP changes your IP prefix. That’s provided by your router doing network address translation. You send a packet from your address which is 192.168.0.42 (a local address), and your router changes the bytes in the packet so that it comes from X.Y.Z.W (your router’s public address). If you really wanted it to your router could do the same thing for IPv6.
IPv6 also has local addresses, but a lot more of them. Anything starting with fd00::/8 is a local address with 40 bits available as the network number. So you can set up your local network with the prefix fdXX:XXXX:XXXX::/48 (where the Xs are chosen randomly) as the prefix and still have 16 bits left over for different subnets if you want. These addresses do not change when your ISP changes your public prefix.
And if you want to add reverse dns for SLAAC addresses then just have your router listen for ICMPv6 Neighbor Announcement addresses and use them to update your DNS server as appropriate. Or configure your servers to use stable addresses based on their MAC address rather than random addresses (which are better for privacy), and then just configure the DNS as you add and remove servers.
Keep in mind the WAN AND LAN preferences associated.
what servers?
The things on your LAN that you're connecting to via DNS and IP, which cause the desire to have stable LAN IPs in the first place.
That's what DNS is for... to not need to remember or know numerical addresses.
And DNS is easier to set up if the IP doesn't change constantly.
This conversation is going in circles.
If you're doing your DNS properly it's not really that difficult. If you're statically definining all your DNS you're doing it wrong.
Okay, how do I properly set DNS so it tracks the changing public addresses of my desktop and printer? And I'd better still be able to use SLAAC.
You register addresses based on Router/Neighbor Advertisements in NDP. In your RA, you'd point it to your DNS server, which would then handle registration when hosts check in with their new IP addresses.
Which dns server supports this kind of dynamic dns in practice?
Wow look, DNS has the solutions!
How, exactly, pray tell, is "properly"?