[120340] in North American Network Operators' Group
Re: DNS question, null MX records
daemon@ATHENA.MIT.EDU (Douglas Otis)
Wed Dec 16 19:03:47 2009
Date: Wed, 16 Dec 2009 16:02:56 -0800
From: Douglas Otis <dotis@mail-abuse.org>
To: Tony Finch <dot@dotat.at>
In-Reply-To: <alpine.LSU.2.00.0912161158110.3461@hermes-1.csi.cam.ac.uk>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On 12/16/09 3:59 AM, Tony Finch wrote:
> On Wed, 16 Dec 2009, Mark Andrews wrote:
>> Douglas Otis wrote:
>>>
>>> One might instead consider using:
>>>
>>> example.com. IN MX 0 192.0.2.0
>>> IN MX 10 192.0.2.1
>>> ...
>>> IN MX 90 192.0.2.9
>>
>> Which will expand to:
>>
>> example.com. IN MX 0 192.0.2.0.example.com.
>> IN MX 10 192.0.2.1.example.com.
>> ....
>> IN MX 90 192.0.2.9.example.com.
>>
>> MX records DO NOT take IP addresses.
Sorry for embarrassing mistake.
To avoid server access and hitting roots:
host-1.example.com. IN A 192.0.2.0
...
host-10.example.com. IN A 192.0.2.9
example.com. IN MX 0 host-1.example.com.
...
example.com. IN MX 90 host-10.example.com.
-Doug
