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bioemerl

Amen.

I had the thankful joy of looking into how DCHP works for a local ipv6 network.

It doesn't.

Android literally just ignores it.

So, want to set a static IP? Can't do it because half the devices people have just flat out refused to support it.

That means ipv6 doesn't even support all the features of V4, and you have less control of your network when you use it. Have a server you want with a known IP address? You can't do it. Not as far as I could see.

The solution? Have server itself runs a program to update your DNS to the right address.

It's so silly and convoluted. I'm sure there are reasons for it, but it's not something I was prone to adopt after looking into it

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IPv6 was designed to not need DHCP. That design was based on 1990's assumptions about privacy, unfortunately.

And assumptions about assignement of IPv6 addresse in the wild.

You will not subnet /64 without DHCPv6, even though you might need to.

SLAAC IPv6 addresses are static IPs; they're directly derived from MAC addresses. Clients will usually receive additional IP addresses as part of the privacy extensions, but static IPs are enabled by default unless you're rotating the address space for some obscure reason. Both IP addresses will work, though for server purposes you obviously use the static addresses.

Basically, you have a static IP unless you have some kind of DHCP server telling you what address you should use instead. Even if your external IP changes, the "internal" part of your IP will remain exactly the same, despite being a routable device.

Maybe some shitty ISPs do this to extort customers into paying extra for static ranges? From the stories I've heard, I believe that some kind of American ISPs shuffles around ranges every week.

Either way, this is the same problem IPv4 suffers from: your external IP is often not static.

DHCPv6 works just fine with everything else I have on my network. Blame Android developers for being pigheaded.

That's just Android's problem. (and not all of Android, Huawei devices seem to work with DHCPv6).

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