Path: utzoo!utgpu!news-server.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!rutgers!netnews.upenn.edu!DCCS.UPENN.EDU!hagan
From: hagan@DCCS.UPENN.EDU (John Dotts Hagan)
Newsgroups: comp.protocols.tcp-ip.domains
Subject: Re: BIND bug list
Message-ID: <25358@netnews.upenn.edu>
Date: 30 May 90 05:46:45 GMT
References: <1990May17.083447.6880@mlb.semi.harris.com>
Sender: news@netnews.upenn.edu
Reply-To: hagan@DCCS.UPENN.EDU (John Dotts Hagan)
Organization: DCCS
Lines: 29


This is not directly about bind itself, and is not actually a bug.  So right
of, my subject is bad - sorry!

Anyways, it think it would be real neat of the resolver did some kind of
performance/reliability remembering when going at its list of possible name
servers to use.

As it is now, we have three name servers for our campus (one is primary, and
two secondaries).  One of the secondaries is listed first in everyone's
resolv.conf (or equivilent list of servers), and then the primary, and then
the second secondary.

When the first listed secondary dies (either named dumps core and leaves, or
the system is toasted), everyone's resolver gets slow since it patiently tries
to query the first listed name server, then after a timeout moves on the the
next one, and so forth.  However, it does not remember that it just had some
trouble with the first server, and tries it again for the next request.

It would be great if the first user who tries a telnet (or whatever) suffered
the hit once for that host, then other tries would quickly just go at a working
name server.  Perhaps dead name servers could be routinely retried and some
stats kept on them (I think bind already does this sort of thing when dealing
with the list of root servers, so at least there is some precedent for this
kind of behavior).

Any thoughts?

--Kid.