[Mailman-developers] Re: [meta-sig] mailman problems

[Ken Manheimer]

On Mon, 27 Apr 1998, John Viega wrote:

>  > "John Viega" <jtv2j@cs.virginia.edu> wrote: 
> > > 1) DNS lookup can be slow.  People want instant feedback.
> > 
> > People also want correct operation.  Seriously, how long can a DNS lookup
> > take?  We're talking about subscribing to a mailing list.  This is not an
> > operation one does dozens of times a day.  If it takes an extra 15 seconds,
> > who cares?
> 
> I've seen it take several minutes when a DNS server is quite loaded.
> I frequently see lookups that take 10-20 seconds. The vast majority of
> users are typing in the correct thing anyway, and don't want to have
> to wait around.  I'd prefer to catch the most common stuff, and give a
> speedy response saying, "If you don't get mail from us soon, try
> again, because we couldn't send mail to your address".

(I'm in the middle of something or i would have responded to several of
the items going around at the moment, but i thought i'd chime in on this
one immediately.  I had also thought about querying the dns to do the
address validation, but my gut feeling is that we can't assume we'll be
able to do that everywhere in a portable way.  I don't even know that we
can presume that dns is used everywhere that might run mailman - they
might use another name service, like nis/nis+, to deliver global host
resolution to individual hosts at the site...)

(ken)