Re: [cobalt-users] DNS reverse address lookup, Raq3i

[Gerald Waugh <gwaugh@xxxxxxxxxxxxxxxxxxxxxxx>]

On Tuesday 29 October 2002 04:02 pm, jale@xxxxxxxxxx wrote:
> A couple of weeks back there was a post, maybe from Jeff Lasman, that said
> there should not be Automatic Reverse Address Record Generation records for
> each domain.

I am sure that Jeff Lasman did not say that.
You need one reverse ptr record per IP address.
And even then unless you have been delegated authority for the ip addresses 
it probably is a useless exercise.

> When we setup our DNS, we went by the book, which had us do that, so for
> each domain, I have:
>
> 1) domain.com --> ip address
> 2) www.domain.com --> ip address
> 3) ip address --> domain.com (27 bit)
> 4) ip address --> www.domain.com (27 bit)
> 5) domain.com --> high speed mail server www.domain.com

That looks OK, but the 'book' says you should have two mailservers.
27 bit, does that mean you have a /27 subnet?
32 IP addresses 1, for network, one for gateway and one for broadcast
so you have 29 useable IP addresses.
Have you been delegated authority for the /27 subnet?

> All "appears" to work fine, but I want to clean up my DNS if this is setup
> incorrectly. So my questions:
> 1) should each domain NOT have its own reverse PTR record (# 3, 4 above)?

It should be '3' not 4
More than one is a waste, bind will take the first record for an ip address 
in the .in-addr.arpa file. It won't break anything, but it is redundant.

> 2) should there be one reverse PTR record ... per server? per IP? Not at
> all?

One ptr record for IP

> Not having one for each domain would be very convenient, it would speed up
> my DNS work as I don't have to create the extra entry which I have to edit
> to change the default 24 bit to 27 bit for my subnet mask.

-- 
Gerald Waugh 
http://frontstreetnetworks.com         http://raqware.com
Front Street Networks LLC   Phone: +1 203 785 0699
229 Front Street, Ste. C, New Haven CT 06513-3203