I can find very little info on 'bgp bestpath as-path multipath-relax' Is this per-packet, or per-flow load balancing?
How much memory usage would it increase assuming 2-3 full tables in memory already (around 400Mb usage, 1Gb RAM)? Looks like you've got 2 defaults only. -- Randy ---------- Original Message ----------- From: Andrew Tolstykh <[email protected]> To: amps <[email protected]> Cc: [email protected] Sent: Tue, 18 May 2010 16:29:52 +1000 Subject: Re: [c-nsp] BGP load balancing (outbound) > ECMP load balancing works with the hidden "bgp bestpath as-path > multipath-relax" command applied (thanks Anton!) > > router bgp XXX > maximum-paths 2 > bgp bestpath as-path multipath-relax > > sh ip route bgp > B* 0.0.0.0/0 [20/0] via 13.13.13.3, 00:05:59 > [20/0] via 12.12.12.2, 00:05:59 > > sho ip cef 0.0.0.0 0.0.0.0 > 0.0.0.0/0 > nexthop 12.12.12.2 FastEthernet1/0 > nexthop 13.13.13.3 FastEthernet1/1 > > If you are after the per-AS load-sharing configuration, then you > should probably flip route-map TRANSIT-1-INT permit 10 and 20 statements. > Also don't forget to add blank "route-map TRANSIT-2-IN permit 20" statement. > > route-map TRANSIT-1-IN permit 10 > match as-path 105 > set local-preference 210 > route-map TRANSIT-1-IN permit 20 > > route-map TRANSIT-2-IN permit 10 > match as-path 106 > set local-preference 210 > route-map TRANSIT-2-IN permit 20 > > HTH, > Andrew > > On 18/05/2010, at 2:42 AM, amps wrote: > > > Let's say I wanted to send traffic to even AS's out peer 1 and odd AS's out peer 2. > > > > Am I crazy? (Seems better than using metrics based solely on static IP ranges...) > > > > Would this work? > > > > route-map TRANSIT-1-IN permit 10 > > set as-path prepend last-as 1 > > ! > > route-map TRANSIT-1-IN permit 20 > > match as-path 105 > > set local-preference 210 > > ! > > > > route-map TRANSIT-2-OUT permit 10 > > set as-path prepend xxxxx > > ! > > > > route-map TRANSIT-2-IN permit 10 > > match as-path 106 > > set local-preference 210 > > ! > > > > route-map TRANSIT-2-OUT permit 10 > > ! > > > > ip as-path access-list 105 permit [02468]$ > > > > ip as-path access-list 106 permit [13579]$ > > > > > > On Mon, May 17, 2010 at 10:59 AM, Anton Kapela <[email protected]> wrote: > > On Mon, May 17, 2010 at 10:42 AM, Andrew Tolstykh <[email protected]> wrote: > > > Just a shot in the dark, but I don't see load balancing enabled in your configuration snippet: > > > > > > router bgp xxxxx > > > > This question comes up semi-often, perhaps there ought to be a FAQ? (I > > may have missed it). > > > > For different-upstream AS's, ecmp will not normally occur. You'll need > > to adjust the bgp bestpath determination functions, else the different > > next-AS's will prevent ECMP forwarding from being pushed to the FIB. > > > > http://puck.nether.net/pipermail/cisco-nsp/2005-November/025993.html > > > > -Tk > > > > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ ------- End of Original Message ------- _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
