queries for IPV6 records on IPV4-only machine.

[Greg Rivers]

On Monday, 7 September 2020 17:46:47 CDT L. A. Walsh wrote:
> 
> I am having some queries that I wouldn't think I'd have:
> 
> I have a split-view ipv4-only named 9.11.2 server that is run with the
> "-4" switch, yet I see attempted queries in my queries log.  I have it
> set as authoritative for the internal domain (though technically I think
> it is classified as a lame delegation), and caching only for everything
> else.
> 
> First I'll see some server name:
> 
> 05-Sep-2020 15:30:23.374 queries: info: client @0x7fbcb804e720 
> 127.0.0.1#36542 (PeerSrv.org): view internal: query: PeerSrv.org IN AAAA 
> + (127.0.0.1)
> 
> followed by a 2nd one:
> 
> 05-Sep-2020 15:30:24.316 queries: info: client @0x7fbce40d5100 
> 127.0.0.1#36542 (PeerSrv.org.internal.Tlinx.org): view internal: 
> query:PeerSrv.org.internal.Tlinx.org IN AAAA + (127.0.0.1)
> 
> Where internal is a subdomain within tlinx.org.
> 
> Am wondering why I'm seeing _any_ IPV6 lookups and wondering why I
> see a 2nd lookup with the query looking for the domain inside my internal
> domain.
> 
> Anyone seen this behavior before?
> 
> It probably doesn't add up to even 1% of my lookups, but I am
> curious.
> 
Those are not "IPv6 queries", they are queries over IPv4 for AAAA records, sourced from the IPv4 loopback address of your own DNS server. It's common for resolver libraries to ask for both A and AAAA records. The fact that you have constrained your named to use only IPv4 transport does not change that behavior.

-- 
Greg