DNS implementation in a pure UNIX environment?

[Kevin Darcy]

>Thanks guys,
>
>I understand the basics I just didn't ask the right
>question I'm afraid...
>
>What I'm looking for is a document on how to switch
>from the hosts file name resolution to a DNS-based one
>in a live, production environment.
>
>What are the pitfalls and how to get every hosts to
>suddenly change the name resolution without bringing
>the whole network down.
>If there's any case study than it would be really
>great!
>
Dump the hosts file into DNS zones (I've heard the "h2n" utility is good 
to use for such migrations, although I've never used it myself), with a 
"catch-all" zone for all of the shortnames. Make sure to "sundown" that 
catch-all zone, though, i.e. no new entries can be added to it, so that 
you start on the right path to weaning your users off their 
shortname-lookup addiction, if they have one. Once you go to DNS, 
everyone should start forming new FQDN habits, because that's the only 
naming methodology that scales properly when DNS is the backend. Even 
having a single "default domain" per location -- a common practice in 
Days Gone By -- is iffy once you start dealing with users that roam 
between locations, unless of course, you want to put everything in a 
single domain, or unless you want to add aliases for *every* possible 
name in *every* subdomain you have...

If you want to do this migration incrementally, then you may be stuck 
with parallel maintenance for a while. It'll help, of course, if you 
have a relatively-logical domain/subdomain/zone structure, so that you 
have a clear idea at any given point in the migration what still needs 
to be maintained in parallel and what doesn't.

                                                                         
                                                         - Kevin