[AusNOG] IPv6 reverse DNS and Mail ...

[Karl Auer]

On Wed, 2013-05-22 at 08:06 +1000, Noel Butler wrote:
> > Its also potential a large number of potential false positives. 
> Potential? Yes, but due to number of (or should I say lack there of)
> complaints, the reality is very different.

Sure. I was talking about the IPv6 world, where reverse lookups will
initially be way less common, and later, ubiquitously synthesised. In
the first case your level of FPs goes up; in the second case there is
literally no point because everyone will have an rDNS entry regardless.
Which latter, I do realise, makes the rest of this message less
relevant :-)

> OK, so for residential customers, well, how many mail servers do you
> want on your home LAN? I dunno bout you, but I only need one (my sec's
> are off-site of course)

How many you need now, and how many you think you will need in the
future is irrelevant. You don't know how many *I* will want, or my
neighbour down the road, or that bright Chinese kid with the great new
idea, or the kid with fifty virtuals in his garage who will, when he
gets them out into a data center or two, be the next Zuckerberg, Page or
Gates.

IPv6 will open up a wealth of new ways to do things, many of which we
see only dimly now, or not at all.

> That's only because bind's GENERATE option was not changed to work with
> IPv6

Um, you can't "change" it, you need to replace it completely. The
mechanism it uses is fundamentally incompatible with IPv6 (at least as
far as rDNS and current common practice are concerned).

Regards, K.

-- 
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Karl Auer                                          tel  +61-2-64957435
kauer at into6.com.au                                 mob  +61-428-957160
                                         
Into6 - IPv6 design, support, training                www.into6.com.au

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