[j-nsp] JUNOS resolves indirect next-hops using other BGP routes

[Tore Anderson]

* Pekka Savola

> This is a feature.  Why should BGP next-hop resolution not be able to
> use BGP routes?  There could be more specifics that give the right
> information.

Because I don't want a route from AS3307 to end up routing packets to
anything but AS3307, not to AS11552 as happened in my test case.
Fortunatly I buy global transit from both of those, so the packets would
reach its end destination anyway, but if AS11552 had only provided me
with, say, "European transit" I might not have been so lucky.

As I understand it the whole point of indirect next-hop resolution is
for a BGP router to determine which other BGP router in the same AS has
the next-hop of the route directly connected, so that the packet can be
sent there and the route be used as advertised.  At least that's the
most common scenario, and the only one the documentation of next-hop
resolving discusses.

> You can adjust the route resolution policy with 'routing-options
> resolution rib inetX-X import FOO'.  That's what we do to exclude e.g.
> our default discard route from affecting nexthop feasibility algorithm.

Great, thank you!  That was what I was looking for.  The following seems
to have done the trick:

policy-options {
    policy-statement accept-igp-only {
        term 1 {
            from protocol [ ospf ospf3 ];
            then accept;
        }
        then reject;
    }
}
routing-options {
    resolution {
        rib inet.0 {
            import accept-igp-only;
        }
    }
}

Best regards,
-- 
Tore Anderson
Redpill Linpro AS - http://www.redpill-linpro.com/