nanog mailing list archives
Re: BGP offloading (fixing legacy router BGP scalability issues)
From: William Herrin <bill () herrin us>
Date: Thu, 2 Apr 2015 19:21:08 -0400
On Wed, Apr 1, 2015 at 1:01 PM, Frederik Kriewitz <frederik () kriewitz eu> wrote:
In practice the biggest problem with [Cisco 6500s] is their poor BGP scalability due to the CPU/memory limitations.
Hi Frederik: Are you sure about that? I would expect you to hit the wall on the TCAM long before CPU/RAM limitations. Check your log for errors along the lines of "FIB_EXCEPTION: FIB TCAM exception, Some entries will be software switched." This might be masked as a CPU problem since routing for destinations which fall out of the TCAM is forced up to the main CPU. If this is your problem and you're talking about sup-720-3bxl's with a 1M TCAM, you can change how much of the TCAM is allocated to which functions for now. Longer term, you either upgrade to something with a bigger TCAM or you reduce the number of routes you carry by introducing superset routes such as a default route and then filtering out the more-specifics your customers are least likely to use. Regards, Bill Herrin -- William Herrin ................ herrin () dirtside com bill () herrin us Owner, Dirtside Systems ......... Web: <http://www.dirtside.com/>
Current thread:
- Re: BGP offloading (fixing legacy router BGP scalability issues), (continued)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Paul S. (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Colin Johnston (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Mark Tinka (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Colin Johnston (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Mark Tinka (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Colin Johnston (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Bryan Tong (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Faisal Imtiaz (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Colin Johnston (Apr 02)
- Re: BGP offloading (fixing legacy router BGP scalability issues) Ćukasz Bromirski (Apr 09)