I have a client that would like to implement 2 7603's at their internet edge. They will be connecting to 2 isp's and advertising bgp. They would like to use the 2 7603's with 48 port gigabit ethernet switch modules and a fwsm's as their entire internet edge. For some reason, they don't want to layer with Router > switch > firewall....don't ask..i've argued with them but they don't listen. The 2 routers will connect to dual 6506's w/sup720' which will act as the core. Is it possible to trunk the two routers together? im thinking i can terminate each isp link into a layer 3 port, then create a vlan where the outside interface of the fwsm will sit, I believe i can run the fwsm in multiple context mode which will allow fw to run active/active, not sure if this would be the best mode for this configuration. Since they will be taking the default route only i can probably just redistribute the default route via ospf or eigrp into fw. Does anyone have experience with 7603's w/ethernet switchmodule and dual fwsm's? I want to make sure this will work without layering multiple devices.
any ideas, thoughts or suggestions would be appreciated. Thanks.