Re: No. of routers carrying full routes?

[dlc () silcom com (David Carmean)]

In a previous message, Alan Hannan wrote:
> [ Dave wrote: ]
>
> > I need to convince someone that singly-homed customer route flaps/
> > withdrawals should *not* propagate beyond our AS. I've found some 
> > discussion of this in the July NANOG archives, and talk about cisco 
> > floating statics, etc... and that "one-way" traffic is insignificant.
>
>   Uhm, I'm not sure the concensus was that they shouldn't.  I
>   believe most everyone would agree that flaps w/in CIDR blocks
>   should not propogate, and that people should only announce the
>   most general network possible.
>
>   But, if you've got a customer singly-homed to me, ideally, from an
>   architecturely scalable point of view, you would do well to static
>   them to your aggregation/POP router.
>
>   However, I'm not sure a quorum agreed that single-homed customers
>   should show up in backbone tables if their routes are/were down.
>
>   There are points to be made both ways, but the BB routing tables
>   are meant to be a snapshot of the net, and if a vector points to
>   provider P, and customer C is not reachable there, I don't really
>   think P should announce such....


Well, if C is aggregated into one of my blocks, and they go away for 
a while, I'm gonna either blackhole it or send an Unreachable.  The 
same as I would if their non-aggregated route is not withdrawn.  CIDR/
aggregation pushes this out to the edges anyway, so I'd think that this 
is of far lesser consequence than thrashing the defaultless/core routers.

I suppose the folks who run said routers would know more than I could 
at this point....

--
David Carmean           WB6YZM          DC574           <dlc () silcom com>
        System/Network Administration, Silicon Beach Communications
Unsolicited commercial e-mail not accepted.  Violators will be LARTed.
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