Can you please help point out a good may to multi-home? I would like to get a site put in a Co-lo in the west coast and one in the east coast. Both would be different co-lo's. Could I get a single ASN and handle both places with different subnets under the same ASN?
Yes but it's kludgy as your West coast router's BGP loop detection algorithm will cause it to ignore the routes to your East coast colo that are heard from your West coast upstream. You can fix this, for instance, by defaulting to a network originated by your upstream. I am assuming you send different subnets to your upstream(s) at either site; if both subnets together form a supernet and you use the same upstream, you can also send that same supernet from both East and West coasts and mark the subnets no-export which should (a) save on prefixes and (b) mean your advertized route is larger and less likely to get filtered / damped. Note you are not (necessarilly) multihoming here as you have two instances of one customer ASN - you are multihoming if you connect one of your sites to more than one upstream. If you only have one upstream on each coast, you may as well use static routes and no BGP at all. -- Alex Bligh VP Core Network, Concentric Network Corporation (formerly GX Networks, Xara Networks)