Subdomain

[Lucio Crusca <lucio@sulweb.org>]

Hello *,

I'm not sure this is on topic, however I don't know wherever else to ask. I
have my Debian Etch server on a static IP address running bind9 for my own
domain (sulweb.org, well bind9 it's not up & running yet, but let's assume
it were).
I'd like to create a subdomain (say dev.sulweb.org) and delegate name
resolution for that subdomain to another Etch DNS (say ns.dev.sulweb.org),
and this alone shouldn't be much of a problem:

$ORIGIN dev.sulweb.org.
@               IN      NS      ns.dev.sulweb.org.
ns              IN      A       xxx.xxx.xxx.xxx

Now the problem is that I'd like xxx.xxx.xxx.xxx to be a dynamic IP address,
so that ns.dev.sulweb.org updates it at sulweb.org in some way similar to
dyndns.com services.

Where should I start from?

Lucio.