Re: [tlug] Reverse DNS Delegatation

[Curt Sampson <cjs@example.com>]

On 2013-07-18 14:33 +0900 (Thu), Pier Fumagalli wrote:

> On Thu, Jul 18, 2013 at 2:02 PM, Curt Sampson <cjs@example.com> wrote:
> >
> > Unless there's a trick I don't remember, they can't do this unless
> > you've contracted for an entire /24 from them, since the zones for
> > in-addr.arpa. records are based on octets within the IP address.
> 
> Hmm? http://tools.ietf.org/html/rfc2317

Ah, right. Duh. Thanks for the, er...pointer. :-)

On 2013-07-18 14:54 +0900 (Thu), Stephen J. Turnbull wrote:

> Isn't it trivial?  Just delegate the whole 1.220.73.198.in-addr.arpa.
> zone....

Yeah, that should work too, though it would be harder to maintain than
the CNAME scheme above.

> If I were an ISP I don't think I'd allow it; it doesn't actually do
> the user any good, but does permit them to screw up a configuration
> that appears to the rest of the world to be under control of the ISP.

I'm with you there; I don't know that I necessarily agree it "appears
to the rest of the world to be under control of the ISP," but that's
not necessarily essential to the argument.

Letting the ISP assign a name to the IP address (while still letting the
client assign other names) makes sense to me for simplicity's sake, and
there at least is a broadly accepted view that systems that can't handle
this are broken (if not accepted by everyone). This does, however, run
in to the usual problems related to "this particular guy won't accept my
e-mail due to configuration bits beyond my control."

cjs
-- 
Curt Sampson         <cjs@example.com>         +81 90 7737 2974

To iterate is human, to recurse divine.
    - L Peter Deutsch