Have you tried Local Pref along with weighting? We have 2 MLX-4, each with a different ISP connecting to them, I know, slightly different than what you have...
We use the LOCAL preference along with weighting to force stuff out our preferred ISP. - Michienne Dixon Network Administrator liNKCity 312 Armour Rd. North Kansas City, MO 64116 www.linkcity.org (816) 412-7990 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Chris Cameron Sent: Thursday, May 28, 2009 2:17 PM To: [email protected] Subject: [f-nsp] BGP design problem We're using a BigIron RX4 with 2.7.0T143 installed. We have two different ISP's (ISP A and B) coming into the same router. We have two /24's, one is "dedicated" for ISP A, the other for ISP B. Should ISP A go down however, the IP block "dedicated" to it can be advertised out ISP B. Traffic is balanced across the two providers through Akamai (content caching service), regardless of best route. This setup as described creates a problem where incoming traffic comes in on ISP A, but on the way out the router decides ISP B is the better outgoing path. To better control our outgoing traffic, we're trying to force traffic to stay on the ISP that it came in on. So that summarizes the problem. We've tried policy based routing, however after testing it seems that it determines a route is dead based on link status, which isn't helpful if an upstream router fails. Policy based routing would work well if it determined a link was "down" based on a BGP route existing or not. We have two ideas that would likely work if we were using IOS, one is virtualizing the router so that we have two routing processes. The other is object tracking using IP SLAs. Multi-VRF sounds like it would do virtualized routing, but it's only listed as supported on the NetIron. I can find nothing like object tracking in the Foundry world. Any one have ideas based either on our problem, or regarding things we've tried? Many thanks, Chris _______________________________________________ foundry-nsp mailing list [email protected] http://puck.nether.net/mailman/listinfo/foundry-nsp _______________________________________________ foundry-nsp mailing list [email protected] http://puck.nether.net/mailman/listinfo/foundry-nsp
