[Dnsmasq-discuss] Split horizon DNS for NATed LAN with auth-server/auth-zone directives

[Eric Engstrom]

In a split horizon situation with an external name server providing the
external resolution of (some) records, I want to be able to have dnsmasq
be authoritative for a NATed subnet (10.7.0.0/16) such that PTR (and
SRV, etc) records are automatically created and returned when queried.

Having read the man page section on "AUTHORITATIVE CONFIGURATION", I
believe the right answer is simply these two directives:

auth-server=mydomain.net
auth-zone=mydomain.net,10.7.0.0/16

Note that I'm NOT putting any interface on the `auth-server` directive.

So, question may be simple: Is that sufficient? Complete?

So far, it appears as if it is both. Resolution of the top-level domain
host (A) record (e.g. mydomain.net) is working correctly, as are local
hostnames and reverse (PTR) lookups. This is working even though I
don't have any `host-record` entries for that or other external-only
resolveable records. Should I be adding those for our top level
domain or for things like MX, even though they would duplicate records I
maintain on our external NS?

FWIW, without those two new directives, including all of my other
configuration to handle the split-horizon situation, including multiple
internal VLANs, using `localize-queries`, and other options as well,
dnsmasq works as I would expect and has for years. I've just lived
without PTR records until now.

Thanks,
Eric