ok, talk me through BGP/IGP interaction one more time. I'm just not getting it

Alright,

So i'm getting ready for my CCNP route exam and the one thing i just can't get my head around still is how BGPs and IGPs interact.

Now, say I have an OSPF network in my AS, it's running all fine and dandy and the ASBR is also running eBGP out to the internet. How do i translate the route to the internet that BGP provides me into the OSPF area?

Obviously it's not redistribution in practice. I've read that BGP will distribute if it detects an identical IGP subnet on it's own routing table (syncronization). But obviously there are subnets that are _not_ going to be identical.

But is the correct process here to create a static route to point to the ASBR running eBGP? Is that the only way or is there a dynamic methodology that interacts between an IGP like OSPF/EIGRP and BGP?

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