There are few things I don't understand.
Using XP/7 on my network that is ipv6 enabled (stateless autoconfig). The router is connected to ipv6 trough HE 6to4 tunnel.

Clients get EUI64 address and the network prefix from the router. Routing and all works.
The thing I noticed, the ipv6 DNS server isn't configured on the clients. The router itself also doesn't have ipv6 DNS servers (ipv4 only that are from my non ipv6 ISP) yet AAAA DNS get properly resolved.

How does that work?


Also when I manually set my router as a ipv6 DNS on the clients Windows prefers AAAA looku??


If somebody could explain how this non native DNSv6 system works...

IPv4 servers can send AAAA records just fine. It doesn't matter how the DNS server is reachable, what matters are the records it returns
When both IPv6 and IPv4 are available to dual stack clients they prefer IPv6.

I presume ipv6 DNS servers don't handle A records?

Had a strange situation just a while ago.
I have some static DNS cache entries (to ipv4 addresses) on mikrotik and the client (W7) had manually configured DNSv6 server pointing to mikrotik.

Yesterdays I was able to resolve those ipv4 addresses from the same client just fine. Today they didn't resolve and had to remove the DNSv6 entry on the client. Then it worked again.

IPv6 name servers can return A records.

The returned records are the DNS payload, and have nothing to do with the layer 3 protocol used by the client to reach the name server. However, the client side resolver would probably query for AAAA records when using IPv6 to reach a name server. Still, the server just answers the question posed to it.