On Wed, 7 Sep 2005, paddy wrote:
I realise that parts of the rDNS network are apparently broken, and I suppose
there must be providers who are just plain uncooperative, and I realise that
sometimes there is simply not a choice of provider.
Is there something about the scenario you describe that naturally leads to
the A record owner not having PTR control, or is it more this kind of
broken system/unfriendly provider issue ?
Are you perhaps talking about the kind of asymetric setup where I have a
domain delegated directly to me and I (perhaps even) host the A records,
so I 'directly' control those, but I have to ask my provider to change the
PTR for me (and thus don't have 'direct' control) ?
Yes - the asymetric setup. When you buy less than 256 IP addresses,
you don't get direct PTR control. You have to ask your provider
to change them and/or delegate them. There is no technical
problem - a competent provider will ask you for a nameserver
to delegate your block to.
For instance, if example.com have a static block of 8 addresses,
10.1.2.128/29, a competent provider will have something like this in
their rDNS server:
$ORIGIN 2.1.10.in-addr.arpa.
128-135 IN NS ns.example.com.
$GENERATE 128-135 $ IN CNAME $.128-135.2.1.10.in-addr.arpa.
And example.com will have this:
Zonefile: example.com
...
ns.example.com IN A 10.1.2.130
...
Zonefile 10.1.2.128-135:
...
$ORIGIN 128-135.2.1.10.in-addr.arpa.
@ IN NS ns.example.com.
129 IN PTR rtr.example.com.
130 IN PTR ns.example.com.
...
The current provider for
bmsi.com delegates each IP individually - I have to setup 6 zone
files with 1 PTR each for our 8 address block.
The ISP zonefile looks like this (for the example above):
...
$ORIGIN 2.1.10.in-addr.arpa.
$GENERATE 128-135 $ IN NS ns.example.com.
...
But at least they delegate (it is T1 based - so there is some provider
competition). Most of our customers are not so lucky.
--
Stuart D. Gathman <stuart(_at_)bmsi(_dot_)com>
Business Management Systems Inc. Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.
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