[Freeipa-devel] DNS use cases

[Simo Sorce]

On Tue, 12 Oct 2010 17:44:24 -0400
Adam Young <ayoung at redhat.com> wrote:

> Really, there are two use cases for creating a zone:
> 
> 1.  I want the IPA server to manage the zone.  it will be the MNAME 
> field for the DNS record.
> 
> 2.   I want IPA to act as the caching server for the zone, which is 
> managed by a remote server.
> 
> The two use cases are mutually exclusive.  It seems that really, only 
> the first makes sense.  The second case is really a degenerate case
> of "act as a caching DNS server for remote server X"  where all
> unresolved queries get forwarded to server X, and the results cached
> for future use.

Minor nitpick on zones and caching.

Being a secondary is technically not just caching. When you are a
secondary, you do zone transfers, and then are able to reply to any
request even those not seen before about a specific record in the zone.
Zones never expire, they just keep being used until the master updates
the zone serial record, at which point the zone is refreshed.

It also involves having the right to issue a zone transfer request.
Something normally not permitted to random clients.

Caching instead is done as part of the normal function of DNS servers
and is applied to all records regardless of where they come from.

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York