How do people do their own RDNS without a full class C ?

[Kyle R. Green]

Let's say you have some addresses in 192.168.0.0/24.  In their 
0.168.192.in-addr.arpa zone, have them put the following:

5     IN     CNAME     192-168-0-5.yourdomain.com
6     IN     CNAME     192-168-0-6.yourdomain.com
7     IN     CNAME     192-168-0-7.yourdomain.com

And in your yourdomain.com zone:

192-168-0-5     IN     PTR     www.yourdomain.com
192-168-0-6     IN     PTR     ftp.yourdomain.com
192-168-0-7     IN     PTR     mail.yourdomain.com

I've seen this in use in a few colo situations, and it generally works 
very well, but they might not want to put CNAMEs in their reverse zones.

Additionally, I'm not 100% sure that this is "proper" DNS.

On Tuesday, January 8, 2002, at 10:19 PM, Patrick Thomas wrote:

>
>
> I have a rack of computers collocated at a datacenter.  I do perform my
> own DNS on my own DNS server, BUT, I do not have an entire class C of
> addresses - I only have 64 addresses.
>
> Therefore, my collocation provider says that I cannot do my own reverse
> DNS.  I cn do my own forward DNS, of course (which I already am) but 
> since
> multiple people are using the class C block, the RDSN requests need to 
> go
> to the collocation providers name servers.
>
> ---
>
> THe problem is this:  I make frequent and manifold changes to my DNS, 
> and
> it will be a major pain for both sides (me and my provider) to have to
> keep communicating changes for their DNS.  We would all be a lot happier
> if I could administer my own RDNS.  But it is too late - they have
> already assigned the other parts of the class C block to other 
> customers,
> so we are sort of locked in.
>
> The questions:
>
> 1. Are we missing something ?  Is there some very elegant and easy
> solution that ISPs generally employ for solving a problem like this, or
> does every ISP customer with less than a class C have to rely on someone
> else for RDNS resolution ?
>
> 2. Let's say there is no way around this, and that they really do have 
> to
> do RDNS for me - we thought that maybe I could maintain correct RDNS
> entries in my name servers and that the ISP could just do a zone 
> transfer
> from my name servers - a zone transfer of only the RDNS records, and 
> thus
> get accurate information in an automated fashion from name server that 
> _I_
> control.  The problem is, my ISP thinks that the only way they could do
> this is by wiping out their entire zone with my entire zone - apparently
> there is no way to simply append my RDNS info to their own using a zone
> transfer.  Is this true ?
>
> They suggested maybe I set up some files to be appended and we do a 
> `scp`
> copy using cron to append the info to their name servers.  This is a 
> good
> idea, but it seems like a hack.
>
> Any other ways out of this conundrum ?
>
> Help and suggestions appreciated.  Thanks!
>
>
--
Kyle R. Green
kyle at kgreen.org

Delores breezed along the surface of her life like a flat stone forever 
skipping along smooth water, rippling reality sporadically but oblivious 
to it consistently, until she finally lost momentum, sank, and due to an 
overdose of flouride as a child which caused her to suffer from chronic 
apathy, doomed herself to lie forever on the floor of her life as 
useless as an appendix and as lonely as a five-hundred pound barbell in 
a steroid-free fitness center.
         -- Winning sentence, 1990 Bulwer-Lytton bad fiction contest.