Reverse DNS RFCs and Recommendations

Wed Oct 30 22:27:24 UTC 2013

On Wed, Oct 30, 2013 at 5:33 PM, Nolan Rollo <nrollo at kw-corp.com> wrote:
> So in the four examples below, 3 of them preface the IP with an alpha
> character. Charter however, starts the rDNS off with a number. I'm
> not arguing with anyone but what potential problems could that
> cause with DNS?

Once upon a time there were buggy software implementations which
looked at the first character of the "name" to decide whether it was a
host name or an IP address. How many of them still exist? Not many
would be my guess.

> 3. Start each section of the name with a letter, not a number or hyphen.

The question I would ask myself is: will I recognize a gain from
putting a digit first in the name instead of a letter? If yes, it's
probably enough of an advantage to not worry about the old
implementations. If no (and it surely seems to be "no" in Nolan's
case) then keep to the conventions that work even with the ancient
buggy crap.

Regards,
Bill Herrin

-- 
William D. Herrin ................ herrin at dirtside.com  bill at herrin.us
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