Re: [cobalt-developers] Proper DNS setup

[Jeff Lasman <jblists@xxxxxxxxxxxxx>]

Kevin D wrote:

> First, whenever I generate an address record, I have read that I should
> generate a reverse-lookup (PTR) record.

Where have you read this?  It's wrong, and someone should fix it.

> If I have multiple domains on a
> single IP, should I still be generating PTR records? (ie have one IP
> pointing at multiple domains?)

You should only have one PTR record per IP#.  And it doesn't necessarily
have to point to any particular machine or domain.  However, by
convention, it should point to the "machine name" of the machine, rather
than a domain.

If the IP# isn't assigned to a machine (yet), or if the machine it's
assigned to changes, you can get away with just assigning it to your
domain name.

> Second, I have been assigned 29 as a subnet, but the automatic reverse
> generation is always IP / 24. I assume I should probably change this to IP /
> 29? I also noticed the warning about non 8 bit subnets - should this concern
> me?

You can only do reverse lookup if your subnet has been allocated to you
for the purpose of reverse DNS.  And that's something your upstream has
to do.  You have nothing to do with it.

Most of us DO NOT do our own reverse DNS; you generally don't get that
right from your upstream unless you've got whole C-blocks or more.

> I also read that telnet is a good harbinger of reverse-DNS problems. When I
> set the RAQ to use itself as primary DNS, I definately do experience telnet
> problems (ie it takes an extremely long time to connect).

Talk to your upstream about who's doing your reverse DNS, and try some
to see what they look like.

Jeff
-- 
Jeff Lasman <jblists@xxxxxxxxxxxxx>
nobaloney.net
P. O. Box 52672
Riverside, CA  92517
voice: (909) 787-8589  *  fax: (909) 782-0205