[99178] in North American Network Operators' Group
Re: Route table growth and hardware limits...talk to the filter
daemon@ATHENA.MIT.EDU (Nathan Ward)
Sat Sep 8 10:56:10 2007
In-Reply-To: <20070908034518.GA77095@ussenterprise.ufp.org>
From: Nathan Ward <nanog@daork.net>
Date: Sun, 9 Sep 2007 02:46:20 +1200
To: Nanog <nanog@nanog.org>
Errors-To: owner-nanog@merit.edu
On 8/09/2007, at 3:45 PM, Leo Bicknell wrote:
> In a message written on Fri, Sep 07, 2007 at 07:14:01PM -0400, Jon
> Lewis wrote:
>> For some reason, today I started out with fewer routes
>> (228289...yesterday,
>> I started with 230686) with no filtering.
>>
>> RIR filter section Reduction in routes
>> APNIC 16690
>> ARIN 41070
>> RIPE 16981
>> LANIC 4468
>> AFRINIC 1516
>> -----------------------------
>> TOTAL 80725
>>
>> The end result of applying all the RIR minimum allocation filters was
>> 147564 BGP routes. I haven't checked to make sure there was no
>> loss in
>> reachability...this is just an idle 7206/NPE225 with nothing but its
>> ethernet uplink.
>
> The CIDR report states that we have 235647 routes that could be
> aggregated to 154503 routes. While not the same metric, I'd be
> surprised at 147,564 routes if you did not have reachability issues.
The difference is roughly 3% of the total prefixes. ((154503-147564)/
235647*100)
It wouldn't be hard to run some form of netflow, and gauge the amount
of traffic to those prefixes. If it's as insignificant as the number
of prefixes, get/use a 0/0 route.
--
Nathan Ward
