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How do you run a DNS server when your address isn't technically static? How do clients discover the DNS server in a SLAAC environment?
Your link local or ULA is static address and can be used for DNS.
DNS server is advertised when prefix is advertised.
> After your router connects to your ISP, the router can ask for prefix delegation. Some providers (eg: Starlink, when I last checked and a Calyx WiFi hotspot) will only advertise a prefix. I was forced to figure out a way to bring the /64 that is in front of my router (Linux iptables) and expose it to a LAN behind my router. It looks something like [1] Depending on your setup, there may be an easier solution. [1] ht…
Without a non-link-local IPv6 address, resolvers will often omit IPv6 addresses in their response.
Another big difference between IPv4 and IPv6 is in the localhost address scheme.
IPv4: 127.0.0.1/8 - 24 bits of free addresses IPv6: ::1/128 - no free addresses
Many people won’t care about this but some local hacks make use the localhost address space for fun and profit.
[1] https://github.com/suntong/dbab/pull/10#issuecomment-1603857...
> After your router connects to your ISP, the router can ask for prefix delegation. Some providers (eg: Starlink, when I last checked and a Calyx WiFi hotspot) will only advertise a prefix. I was forced to figure out a way to bring the /64 that is in front of my router (Linux iptables) and expose it to a LAN behind my router. It looks something like [1] Depending on your setup, there may be an easier solution. [1] ht…
It sounds like you're talking about running a router behind a router which you should try to avoid. If you want to run your own router you should try to put your modem/dish in passthrough mode. Once you do that Starlink works fine.
How do you run a DNS server when your address isn't technically static? How do clients discover the DNS server in a SLAAC environment?
2. Then you have your router advertise that prefix.
3. Then you have your DNS server pick a non-temporary address within that prefix (either manually set it, or let the OS pick one).
4. Then you tell your router to advertise that address as the DNS server in the RA.
Depending on how you have your network set up, your DNS server will have probably four IPv6 addresses: A link-local one; one on the ULA prefix you created; a non-temporary address on the prefix delegated by your ISP; and one or more temporary addresses on the prefix delegated by your ISP.
Outgoing connections (for recursive resolving) will be on one of the temporary addresses from the PD prefix. The DNS server listens on the static ULA address.
You need to configure your firewall such that traffic from the delegated prefix can get to the ULA one, and vice versa. This usually just means blocking traffic from the WAN port to the ULA prefix.
Step 2 says to set up ULAs. Are these static or dynamic? It says "don't pick numbers." If dynamic, how does step 5 work? If static, what about visitors in my house?
Step 3 mentions a LAN DNS. Where do I set that up? I don't recall my router having that option somewhere, and I'd rather not rely on a machine for it.
How do you run a DNS server when your address isn't technically static? How do clients discover the DNS server in a SLAAC environment?
Then there was a bug in CoreDNS that wouldn't bind link local. What I learned from the text is that I should have probably generated a unique address for the DNS.
It is not only confusing theoretically but also the ISP router config makes it even more confusing.
I'm a home ipv4 admin. What I or someone similar would need is the last part that shows how you set up a basic network with some local addresses I care about and a few I want to expose publicly. It's nice that the guide includes the concepts, but the first thing anyone will want to do is just make it work. Step 2 says to set up ULAs. Are these static or dynamic? It says "don't pick numbers." If dynamic, how does step…
It's weird. Personally I've yet to make the jump to IPv6 because it seems too complex, doesn't make sense, so I don't want to spend the mental effort learning it when I have no need to switch. However, looking decades back I realise I felt the same way when first learning about and working with networks. Nothing about it is intuitive. It's all complex, until it isn't through repetition and familiarity. That said, I s…