Re: uri.host is down?

Stephen D. Williams (sdw@lig.net)
Wed, 12 Apr 1995 14:11:45 +0000 (GMT)


Message-Id: <m0rz394-0009tGC@sdwsys>
From: sdw@lig.net (Stephen D. Williams)
Subject: Re: uri.host is down?
To: rdaniel@lanl.gov
Date: Wed, 12 Apr 1995 14:11:45 +0000 (GMT)
Cc: ren@dstc.edu.au, uri@bunyip.com
In-Reply-To: <9504120925.ZM7767@macrdan.acl.lanl.gov> from "Ron Daniel Jr." at Apr 12, 95 09:03:04 am

> 
> On Apr 12,  3:35pm, Renato Iannella wrote:
> 
> > If the URN denotes that uri.host.edu is the
> > name server, what can happen if the ns is down?
> > 
> > Since the "uri" part of the hostname is not 
> > specified in the URN, can we try uri2.host.edu ??
> 
> DNS allows more than one IP address to be associated with a single
> FQDN. Typicaly proactice now is to do a gethostbyname(), look
> at the first IP address, and fail if you can't talk with it. We
> want client writers to be a little more tenacious in this. Keep
> the list of addresses, try one. If it fails try another. Keep
> doing that until you succeed or run out of IP addresses.

I agree!  I was surprised when I noticed a Unix telnet client that
did this.  It's a very good way to do load balancing.

An option to determine the best available IP at a given time would also
be nice.  It could measure round trip, hop count, and response time.


> Ron Daniel Jr.                     email: rdaniel@lanl.gov    
> Advanced Computing Lab             voice: (505) 665 0597
> MS B287                              fax: (505) 665 4939
> Los Alamos National Laboratory      http://www.acl.lanl.gov/~rdaniel/
> Los Alamos, NM  87545          tautology:"Conformity is very popular"
> 
> 


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