I'm looking for suggestions. In my case study scenario, a company has two internet routers which have bgp peering to separate ISPs.
RTR-A peers to ISP-A
RTR-B peers to ISP-B
The two routers have an IBGP connection together.
The Routers are connected to a Firewall which does the PATing. For simplicity reasons, let's say there are only 2 internal network subnets. All routes from ISP-A has a local preference of 800 and all routes from ISP-B has a local preference of 700 so the internal network is taking ISP A.
If I want subnet 2 to take ISP-B, what are some suggestions to handle this?