What is a Round Robin DNS? and other security issues..

[Joseph S D Yao]

On Thu, Jan 27, 2000 at 03:23:06PM -0500, Josh Rivel wrote:
> Round robin DNS = Having multiple ip addresses (A records) for the
> same hostname.
> 
> I.E.
> 
> lame:~> host www.msn.com
> www.msn.com             A       207.46.179.143
> www.msn.com             A       207.46.185.138
> www.msn.com             A       207.46.185.140
> www.msn.com             A       207.46.209.218
> www.msn.com             A       207.46.176.120
> www.msn.com             A       207.46.176.121
> www.msn.com             A       207.46.179.134
> 
> Jari Ivanoff wrote...
> > Sorry for this perhaps trivial question.. but what is a Round Robin DNS??

This answer is incomplete.  It is only "round robin" when the first
answer returned [which is often the only answer looked at] rotates
evenly among all addresses.  This can be undone by cached answers, by
intermediate name servers that do not rotate answers, or by changing
the default sort order on the home name server.

I guess some kind of "true round robin" would preserve the order while
changing the first one presented; but since most clients wouldn't care
about the others, I wouldn't make that a requirement.  I believe that
this behavior is the kind of "round robin" that BIND V8 exhibits,
anyway.

-- 
Joe Yao				jsdy at cospo.osis.gov - Joseph S. D. Yao
COSPO/OSIS Computer Support					EMT-B
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