full-disclosure - Re: Reverse dns (whether you want it or not)

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From: nocmonkey at gmail.com (Danny)
Subject: Re: Reverse dns (whether you want it or not)

On Fri, 11 Mar 2005 13:48:05 -0000, Dave Korn
<davek_throwaway@...mail.com> wrote:
> "TheGesus" wrote in message news:5e70f65305031013083747d7b@...l.gmail.com...
> > On this subject (marginally), last year we moved a rather large CIDR
> > block from one ISP to another.
> >
> > The new ISP took it upon themselves to give *ALL* our unused IP
> > addresses a bogus reverse lookup in the (general) format of
> >
> > 10.20.30.40.abc.domain.com
> >
> > No one asked them to do this (or, at least if they did, they won't
> > admit to it), and none of the reverse lookups can be looked up
> > "forwardly".
> >
> > Is this a common practice?  It doesn't seem like a good idea, but the
> > ISP insisted it was a "value-added" service.  In my opinion, a dead
> > address should remain dead.
> 
>   It's common.  ISPs don't want to have to update their DNS records with
> every single client that logs on or off their network, that would be a lot
> of churn and general overhead for no great purpose.

A lot of churn and general overhead? 

Configure them properly the first time:

123.123.123.123 = host123.clients.nameofyourisp.com

No need to constantly update the DNS records.

...D