about resolving on a child zone

[Chris Buxton]

On Apr 13, 2009, at 6:28 AM, Tech W. wrote:
> hello,
>
>
> I have the domain saying it's example.com.
> I defined a NS (and its A rcd) as below:
>
> my.example.com.  IN  NS  mydns.example.com.
> mydns.example.com.  IN  A  11.22.33.44
>
>
> Also I added this A record in both main DNS and the child zone's DNS  
> (mydns.example.com).
>
> www.my.example.com.  IN  A  55.66.77.88
>
>
> When I query for www.my.example.com, who will respond for it? the  
> main DNS or that mydns?
>
> Can I set only www.my.example.com in main DNS while not in mydns?

You should try it and see what happens. Use named-checkzone to check  
both copies of the zone for errors.

In this case, the answer is that your main zone (example.com) will  
have an error, because it will have an A record below the "bottom" of  
the zone that is not a glue record. In other words, it will recognize  
that www.my.example.com belongs to my.example.com, not to example.com.

Chris Buxton
Professional Services
Men & Mice