I'm working on a practice lab at the moment and trying to understand BGP and default routes in a network. I've attached diagram with a bit of information. From my reading I understand that you shouldn't redistribute BGP into and IGP such as EIGRP. Instead you should use default routes and inject them into your IGP to point towards the default gateway.
In my example I have 3 routers, R7, R5 and R12, running BGP between 2 autonomous systems. I have EIGRP running on both autonomous systems.
Looking at AS711, instead of having a static route, ip route 0.0.0.0 0.0.0.0 fa0/1 or ip route 0.0.0.0 0.0.0.0 fa0/2, which point to either R5 or R12, would it be better to use ip route 0.0.0.0 0.0.0.0 null0 on R7 and then inject this into EIGRP? That way instead just using either fa0/1 or fa0/2 to get to AS 911, the null0 would allow the EIGRP routers to get to R7 and then BGP on R7 would choose the best path to AS911.
Is this the best practice or is there a better way to achieve this?
In the senario you desribe using a EIGRP defuault route to R8, 9 and 10 is valid and is 'normal' for a lot of Enterprise customer where R7 is the CPE of some managed service.