Re: OT: Forwarding to your ISP

In article <cbuoid$1f53$1@sf1.isc.org>,
Kirk Strauser <kirk@strauser.com> wrote:

> On Tuesday 2004-06-29 12:54 pm, Barry Margolin wrote:
> > You don't need to forward to your ISP's nameserver, just let your
> > nameserver work its way down from the root servers.
>
> Barry,
>
> I apologize in advance for bringing this up, but it's always been my
> understanding that the Internet is better off if everyone forwarded their
> requests to their upstream provider (caching and all that). I know this
> has been discussed before, but the usual answer I've heard to the question
> is along the lines of "search the archives". I seem to be Google-impaired
> because I've never found a concise summary of why directly querying the
> root servers is better than forwarding. Any chance you could point me
> toward an explanation somewhere? I'd like to make sure I'm following
> current best practices.

The general concensus is that forwarding simply adds unneeded
complexity. You're dependent on the ISP's servers for something that
your servers can handle perfectly well all by themselves. ISP servers
are already handling a huge load, so it's not uncommon for them to be
overloaded (even the best run ISPs occasionally encounter unexpected
activity, or get deliberate DOS attacks), and you'll suffer as a result.

The only benefit of forwarding to the ISP's server is that you can make
use of records they've already cached because another customer asked for
it. This is helpful when your server is first starting up, but by the
time it has been running for a while it will generally have all the
popular sites cached locally, and it won't need to go out to any server.
Conversely, if there are sites that are accessed by hardly anyone but
you, you'll force the ISP to cache these records even though none of
their other customers are likely to benefit (and even you won't benefit
from the ISP's caching, because it's also cached on your server); this
wastes the ISP's resources, impacting all the other customers.

--
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***