2014-04-07 18:29 GMT+02:00 Ondrej Zajicek <santiago@crfreenet.org>:

> Hello
>
> That is because only resolvable routes are considered (RFC 4271 9.1.2.1),
> main reason for that condition is to eliminate routes whose bgp_next_hop
> cannot be resolved using IGP, it also affects routes whose bgp_next_hop
> is resolved to a unreachable/blackhole/prohibit route.
>
> In your case, it could be fixed by adding higher protocol preference
> (different attribute than bgp_local_pref, currently 100) to b_rr1.

Unfortunately increasing the preference of the b_rr1 session is not an
option as from my understanding it would completely eliminate the bgp
route selection rules (All routes learned via b_rr1 are preferred over
b_dtag1).
Is there any other solution for this besides doubling the iBGP
connections (adding seperate blackhole only sessions with higher
preference)?