IBGP problem concerning more specific routes

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1

Here is an amusing BGP problem :

   Wild Wolrd-----------R1--------------R2------Our Networks

There is an IBGP sesion running between R1 and R2. R2 advertises route
194.214.0.0/16 to R1. In our block there is a class C used by one of our
customer which is not directly connected to our network. This customer
advertises its class C to the Wild World via its own ISP.

R1 receives the 194.214.253.0/24 advertisement from the Wild World, it
stores it in its routing table; however R2 never takes it into account :
its routing table only mentions 194.214.0.0/16 , it doesn't mention the
more specific routing entry 194.214.253.0/24.

Our Networks cannot get to 194.214.253.0/24. Is it a feature of IBGP ??

Thanks for any help,

Pascal

2

Routes heard from EBGP only travel one hop into your network when
exported via IBGP. But, this should meet that criteria. Have you
done anything with localpref values or weights? It may be that R2 is
ignoring the specificity of the /24 in deference to the AS Path and
Local AS number of the /16.

-v