"2M today, 10M with no change in technology"? An informal survey.

Eric Gauthier eric at roxanne.org
Mon Aug 27 14:16:09 UTC 2007


> >My understanding is that there are no known algorithms for fast
> >updates (and particularly withdrawals) on aggregated FIBs, especially
> >if those FIBs are stored in CIDR form.  This is the prime reason why
> >all those Cisco 65xx/76xx with MSFC2/PFC2 will be worthless junk in a
> >couple of months.
> Do we have a real date for when this occurs? If you aren't doing uRPF, I 
> thought they ran up to 256,000 routes. (I may not recall correctly)

We ran into this hiccup a few months ago on a Sup720-3B (well, a 3BXL which
mistakenly had a 3B card in the chassis, causing the SUP to clock down and
act like a 3B), but I think the Sup2's are in a similar situtation.  Though 
the box can handle up to 224k routes, they are set by default to only handle 
192k IPv4 + MPLS routes plus 32k IPv6 + IP multicast routes.  You can retune 
this so that you can get up to 224k IPv4 routes, but I've recently seen our 
Internet table bumping against this.  My understanding is that this is a 
hardware limit, so upgrading is your only option.

Eric :)

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