On 02/11/2015 09:56 AM, Gert Doering wrote: > Hi, > > On Tue, Feb 10, 2015 at 03:42:23PM -0800, Joe Pruett wrote: >> with bgp filtering might i be able to install just routes of /20 or >> shorter (hoping that is a small enough number of routes). or would bgp >> still consume all the routes before it filters and thus run out of ram? >> i'd don't think i want to experiment with this in production :-). > > The easiest way is to filter on *export* from the 7200s, so the 6509 > has no chance to see the refused routes at all :-)
yep, i realized that i should control export after i got some other off list responses. > > > If I remember right, Sup2 had 256k FIB, going to half that if you enable > uRPF. So if you set your iBGP-sessions to "max-prefix 230000" (or 115000), > and then experiment with feeding it more and more routes, you should > be fairly safe... my reading of max-prefix doesn't make it very useful. either you reset the session after hitting the max, or you just log a warning and then continue accepting prefixes. i'll just be very stingy with my export to begin with and see how things go. > > [..] >> and from my reading it sounds like even going to a sup 2t wouldn't >> really solve the problem? although most of that discussion seems to be >> external bgp, maybe ibgp wouldn't run into issues? > > A sup2t(-xl) can handle 1 million routes, so that's plenty, but most > serious overkill to get it only for the routing table memory. and it sounds like my line cards might have to be replaced... > > >> oh, and i run full ipv6 as well, just to make it interesting. > > Sup2 and IPv6 is software forwarding, so that might be some reason to > upgrade eventually... so far my cpu is not breathing hard, and i run a routed vlan (with software shaping) for every port. but, overall routed traffic is under 100mb. even my layer 2 traffic rarely makes the little bar graph on the sup2 card flicker. i'm hoping i have years left on this setup. if the ibgp pushes things too hard, i'll just live with the inefficient traffic. _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
