Thanks for the pointers towards eBGP Multipath. Can I check that this still works if two links are terminated on different edge routers (though with iBGP between the edge routers). I assume this will use additional TCAM resources (Sup720-3BXL) in maintaining two routes per prefix, which could be significant for a full BGP feed?
Cheers, Matt -----Original Message----- From: Erik Cuevas [mailto:[email protected]] Sent: 05 February 2010 12:33 To: Matthew Melbourne Subject: RE: [c-nsp] Load-sharing with two links to the same ISP Did you check out BGP multipath? http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094431 .shtml or is the AS Path is different try... bgp bestpath as-path multipath-relax(its hidden) -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Matthew Melbourne Sent: Friday, February 05, 2010 6:33 AM To: [email protected] Subject: [c-nsp] Load-sharing with two links to the same ISP Hi, What techniques are available to load-share traffic on two links (of equal bandwidth) to the same ISP (same AS) given that BGP only enters the best path into the RIB? We could announce our prefixes over both links, but splitting the preferred path announcements over the two links, either using MED or ISP communities, but this only really addresses inbound traffic. More of an issue is trying to load-share outbound traffic; we assume we'll learn the same set of prefixes over both links from the same ISP - one technique may be to simple split the IPv4 address space in half and local-pref accordingly to prefer one link or the other depending on the destination IP prefix? Cheers, Matt -- Matthew Melbourne _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.733 / Virus Database: 271.1.1/2669 - Release Date: 02/05/10 07:35:00 _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
