Multihome BGP - ASA doing NAT, how to route ASA?

[trippi]

We have a Cisco ASA failover pair doing NAT. External to that we have a switch that connects to our two external internet routers. We are in the process of implementing BGP with our ISPs between the two routers. We have been assigned a Class C by each ISP for BGP routing. Both internal interfaces on the routers have external IPs--so I can't run HSRP?? What gateway would I point the Cisco ASA to?? I'm confused at how I should handle the IP addressing/routing from the ASA to the switch to the routers...

[royalblues]

You need to have your own address space for this to exactly work

Have a look at devices like radware linkproof which can dynamically change the NAT based on the availability of links and even loadbalance between different ISPs

http://www.radware.com/Products/ApplicationDelivery/LinkProof/default.aspx

Just before your post i saw a post from Paolo about EEM support on the routers.

http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6555/ps6815/config_guide_eem_configuration_for_cisco_integrated_services_router_platforms.html

HTH

Narayan

[trippi]

There is no way to get this to work with 2 class Cs? One from each provider?

[trippi]

Can I use just one class C from one of the providers? The other is willing to peer that Class C.

[t814687]

BGP routing is not supported on Cisco ASA appliances. I'm not sure how are you going to peer with your ISP. You need a router.

serg

[smitty6504 · Accepted solution]

We have the same setup. This can be done very easly. You need to run an IGP between the router and the ASA. We are using OSPF with default-information originate on both routers. Then set the metic on the router you want to use as your backup ISP. For NATing please look at the link below.

http://www.cisco.com/en/US/products/hw/vpndevc/ps2030/products_configuration_example09186a00806e880b.shtml