As other have written, using communities is the way to go. Here's a list of upstream communities, you can often find more by searching for $UPSTREAM BGP community: https://onestep.net/communities/
Stay away from Hurricane Electric, they have no communities at all. Better to peer directly with them anyway. > Matt Hoppes wrote: > I have a situation where I can buy several 1 gigabit pipes from several top > tier carriers relatively inexpensively. Are you sure you actually want to do that? Four upstream carriers are hard to balance, especially if you are trying to max them out. Before you even get that far, you should determine what your traffic flows per ASN are and base your upstream selection based on that. Worse case scenario, you contract with multiple upstreams and when putting them into production notice that almost no traffic is originated from some. > Or I can buy one fat pipe from one carrier. You don't really want that either. What you want is two or more medium pipes. Say two 2G commits on 10G interfaces or even four 1G commits on 10G interfaces if needs must. Preferrably burstable, of course. That way you can easily handle any one upstream being down. > Say I need 4 gigabits of bandwidth and have four 1 gigabit pipes from 4 > carriers running BGP, is there a best way to load balance these? I'm not saying you can't do this, but it's going to require a lot of fiddling and hand holding. You'll easily max out some interfaces and underutilize others. Turning the BGP knobs is never going to neatly distribute traffic from one interface to the other and any changes can have non-linear effects. > Just AS pre-pend subsets on each carrier so certain subnets prefer one over > another? When it comes down to brass tacks, prepends are just suggestions. They may or may not be heeded. More specific prefixes, tho, will definitely drive traffic. However, it's a rather blunt tool and more of an all or nothing thing and requires that you have a covering supernet for fallback to avoid effectively single homing yourself. > Or is there a better way? Use communities. Jared -- AF mailing list AF@af.afmug.com http://af.afmug.com/mailman/listinfo/af_af.afmug.com