Re: Two simple openssh questions...

From: Nico Kadel-Garcia (nkadel_at_verizon.net)
Date: 08/27/03 

Date: Wed, 27 Aug 2003 03:58:23 GMT

Thomas Binder wrote:

> Hi!
>
> Nico Kadel-Garcia <nkadel@verizon.net> wrote:
>
>>Lack of reverse DNS is not "broken".
>
>
> And where did I state that? I said that if there are delays when
> sshd is trying to reverse lookup the IP, then usually the local
> DNS config is broken. Whether an IP resolves to a hostname or not
> should not have any (noticable) effect on the time the query takes
> when DNS is set up properly.

The DNS is set up "properly". It is not set up *completely* for reverse
DNS, which is not unusual for small sites with /etc/hosts and no local
DNS server in place, and is perfectly acceptable. Providing DNS in such
situations, especially in DHCP based client configurations, is difficult
if not painiful to set up correctly. You basically have to get the DHCP
data, rewrite your named.conf on the fly, generate reverse DNS tables on
the fly, and pray that your DHCP doesn't change for long before your
scans of DHCP updates catch it and rebuild your reverse DNS tables.

Awkward, painful, and unwise.

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