On Thu, Oct 22, 2009 at 12:35:18PM +0100, Nick Hilliard wrote:
> On 22/10/2009 11:30, bmann...@vacation.karoshi.com wrote:
> >On Thu, Oct 22, 2009 at 09:20:11PM +1100, Karl Auer wrote:
> >>The RA contains a preference level... maybe that doesn't cut it if
> >>multiple routers are sending the same preference level, but presumably
> >>that would not happen in a well-tended network.
> >
> > I point you to a fairly common Internet architecture artifact,
> > the exchange point... dozens of routers sharing a common
> > media for peering exchange.
>
> Bill, could you explain how or why ra or dhcp or dhcpv6 have any relevance
> to an IXP? Being one of these "artefact" operators - and clearly stuck
> with a very small dinosaur brain - I am having some trouble understanding
> the point you're attempting to make here.
>
> Nick
its been a few weeks/years/minutes since I ran an exchange fabric,
but when we first turned up IPv6 - the first thing they did was try
to hand all the other routers IPv6 addresses. that pesky RA/ND
thing... had to turn it off ... RA preference would not work, since
there was no -pecking- order - all the routers were peers.
we did the manual configuration - no DHCP - it was the only way to
ensure things would be deterministic. Hence my comments to
Karl re his statement about "not happen in a well-tended network".
the point. RA/ND was designed to solve what some of its designers
thought would be 80% of the problems. It might just be able to
do that - for the limited scope that it has. There are other, more
robust, decomposable, resilient configuration tools out there that
have capabilities people need that are not currently in RA/ND.
and even then, not all architectures are ammenable to automated
configuration tools.
RA/ND is not a panecea.
--bill
