override ttl=0

[Mark Andrews]

> On Sat, 5 Jan 2008, Matus UHLAR - fantomas wrote:
> 
> > On 04.01.08 15:52, Herve Guehl wrote:
> >> My users choosed an external service, based on the fact that is fit their
> >> needs.
> >
> > and you have problem with it. Either accept it as it is, or ask the custome
> r
> > to fix the problem where it lies... I don't think you'll solve anything by
> > breaking the RFC...
> 
> I think its very reasonable to enforce a minimum of at least 1 hour
> many large networks do this, because we all know how many other 
> incompetant people there are out there in control of their own DNS
> 
> > Maybe you and them should rethink what does "their needs" mean and what wil
> l
> > happen if it will continue causing the problem. Maybe if you converted "you
> r
> 
> It's barely noticable if a locally hosted domain has a laughable TTL like 
> 10m, but image if you host 30K domains, and every one of these idiots set 
> their TTL to 10 mins, think of the un-necessary bandwith and workload 
> those servers have to do when its not called for,  IIRC it wont accept 
> anything less than 10 minutes anyway, but in a day when no one runs 
> servers on dynamically assigned IP servers, I think the built in default 
> should be 1 hour at the very least.

	Well people do run things on dynamic address these days.
	The TTL of those addresses is usually derived from the DHCP
	lease parameters.  If you have a 1 hour DHCP lease then the
	DNS TTL should be about 15 minutes.  That allows for 1
	missed DHCP renew.

	People do you run ttl's down when they are about to switch
	servers.

	Yes, the DNS does suffer from the tragedy of commons.  That's
	why education is important.  Everyone should be doing the
	right thing and when you see someone doing the wrong thing
	you inform them.  You don't just let them continue as it
	just makes things worse regardless of what "fixes" you might
	attempt.

	Mark
 
> -- 
> Cheers
> Res
> 
> mysql> update auth set Framed-IP-Address='127.0.0.127' where user= 'troll';
> 
> 
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org