stub zones ,redundancy and DDNS

[mmccaws2]

behind the firewall we have two domains, unrelated by name.  The first
domain is registered and the second is a AD forest non-routable domain
like domain.local.  The site's primary domain is configured on the
site's primary nameserver.  The AD is configure as it's own primary and
the primary name server has the AD as a stub zone.

The question is about resolving fully qualified host names from the AD
domain in the primary name server. If the AD DNS server goes down,
could anyone resolve those domain's hosts from the primary. Since the
AD is configured as a stub zone on the primary name server, would any
entries for the AD zone ever be resolved if the AD nameserver goes
down?  How about if they are entered as static entries?  Basically once
a name server has a stub zone configured will it try to resolve it from
it's own records if the nameserver for the stub zone is down?


primary name server
zone:
publicdomainname.com
 stub zone:
AD domain.local

Does it make sense to run the DHCP services for  the AD domain from the
primary DNS server?

Mike