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Date:      Fri, 13 Jul 2007 15:56:56 -0400
From:      Steve Bertrand <>
To:        Chuck Swiger <>
Cc:        "freebsd-questions@FreeBSD. ORG" <>
Subject:   Re: is is able to setting up DNS server reverse lookup	with	DynamicIP?
Message-ID:  <>
In-Reply-To: <>
References:  <>	<>	<> <>

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Chuck Swiger wrote:
> On Jul 13, 2007, at 10:44 AM, Dan Casey wrote:
>>>> I'm using dynamicDNS, so I will able to specify the forward *AND*
>>>> reverse lookups?
>>> No.  Reverse lookups are controlled by whoever owns the IP delegation
>>> for the netblock in question, and they are not going to configure PTR
>>> records for dynamic IPs.  If you want to have reverse lookups you
>>> control, you'll need to get static IPs.
>> Slight correction.  To do what you want, you will need to get a static
>> ip.  Then you can request your isp (or whoever owns the ip block) to
>> setup the PTR record for you.
> That's not really a correction.  :-)

Correct ;)

> If you get a single static IP, for example, normally the ISP or netblock
> owner will not delegate that, but are willing to setup a PTR record.

That is, if the ISP *is* willing to set up a rDNS entry. I have had
clients move from their previous provider to us because the old provider
would not set up a reverse DNS entry for their statically assigned
IP(s). Sounds bad, but it happens.

> If you get a larger static netblock, especially a /24 or larger, then
> your ISP can delegate reverse DNS to nameservers you run, and thus you
> can set up and change the reverse lookup results at will without needing
> your ISP to make PTR record changes.  See
> about "Classless IN-ADDR.ARPA
> delegation" for the deal with regard to delegation of smaller netblocks
> than a /24.

I personally wouldn't do this. If anything, I would delegate permissions
on our name servers so that the client can log in to our DNS interface
and make the changes there. That way, we always have control over the
names in the event you ever have a rogue employee at the other end.

However, we don't do anything of the sort. When clients need rDNS
entries changed, the client requests it, and we make it so. It is the
same way that we work with one of our external ADSL wholesalers.

Mind you, when you call us, someone answers the phone. You can ask for
the button pushers directly, and changes are made live time mostly. Try
that with a Sympatico, AOL or the like.


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