[dns-wg] Turning off lameness checks for reverse

On 31 Mar 2009, at 08:32, B C wrote:

> On Sat, Mar 28, 2009 at 7:55 PM, Shane Kerr <shane at time- 
> travellers.org> wrote:
>
>> 2. As far as I know there has never been a study showing  
>> improvement for
>>   DNS users based on removing lameness in reverse DNS (or in any  
>> DNS).
>
> I'm not aware of any study either but I think we are all aware that
> certain applications work much better if reverse DNS is setup and
> functioning correctly. If those applications no longer had a
> dependency on reverse dns working then I may find it easier to agree
> with your point of view.

A lame delegation (a delegation to a working nameserver which does not  
offer an authoritative answer to the question) might well have similar  
impact on application to the case where there is no delegation at all.  
In both cases you get some form of negative response that indicates  
that the reverse mapping is not available.

Delegations to nameservers which don't respond probably cause more  
annoyance than lame delegations, since they involve a timeout. Note  
that if the nameserver doesn't respond you can't tell whether the  
delegation is lame or not.

Encouraging peoople to fix unresponsive nameservers seems like a more  
obviously good idea than encouraging people to fix measurably-lame  
delegations.

The other consideration that has come up in other regions (and which I  
have also not seen a study supporting) is that lame delegations caused  
increased traffic for the servers that publish them, and that the  
increased traffic presents an operational problem.

Philosophically, it makes sense to me for the zone operator (the NCC)  
to care about the accuracy of the data published in the zone. It's not  
clear to me that doing so has any operational benefit to the NCC,  
however.

What I hear Shane saying is that since he sees no operational benefit  
in the checks, as the operator of the number resource, he ought to  
have the option of opting out of them. I note that opting out of lame  
delegation checks is possible at ARIN (since I happened to get some  
robot lame delegation checker mail from them the other day, and the  
mail mentioned it).


Joe