iBGP Routing Question

I am hoping someone can shed some light on why this route is not being advertised via iBGP between two routers.

The layout is as follows (hopefully the drawing will format right): AS 1 (0.0.0.0) | \\ | -------------------- AS 2 | | | | | AS 3 (WEST) ----AS 3 (EAST)

Summary: AS 1 is advertising 0.0.0.0 to AS 2 and AS 3. AS 3 WEST router connected to AS 2 router receives the 0.0.0.0 via AS PATH 2, 1 AS 3 EAST router connected to AS 1 router received the 0.0.0.0 via AS PATH 1

In the BGP table for the AS 3 WEST router shows both of the routes

0.0.0.0 via AS 1 0.0.0.0 via AS 2, 1

In the BGP table for the AS 3 EAST router we only see

0.0.0.0 via AS 1

Question: Why in the bgp table for AS 3 EAST wouldn't we also see the route

0.0.0.0 via AS 2, 1.

When checking the advertised routes from AS 3 WEST to AS 3 EAST its not being advertised. There is absolutely no route filtering happening between the iBGP routers.

The only thing I can think of is that AS 3 WEST sees the better path from AS 3 EAST and decides not to send its 0.0.0.0 route to AS 3 EAST.

My expectation would be that both "sh ip bgp" on each router would have listed the 0.0.0.0 route, but that clearly is not the case in my lab.

Amy.