I need your help in designing the dual isp scenarios. There are 2 cisco routers installed as edge internet routers. Each router's WAN connected to defferent ISP.The gigabit 0/0 of both routers are connected in the common 172.20.21.0 network segment with hsrp VIP 172.20.21.1. The physical interface IP of those routers is 172.20.21.5, 172.20.21.6. The failover firewall outside interface connected to this same segment with IP of 172.20.21.3 and 172.20.21.4. The firewall default gateway is HSRP VIP of router 172.20.21.1.
Please help me how can we achieve the dual ISP load balancing using those 2 separate rouetrs. If one router fails another should take over as redundant router.
Thanks in advance