[j-nsp] Many contributing routes

[Alexander Marhold]

Yes, you are right  the primary contributing route is the mathematically
lowest 32-bit number of routes in that case
"Show route x.x.x.x extensive" shows the primary contributing route at the
end of the displayed output.

Regards

alexander

-----Ursprüngliche Nachricht-----
Von: Aaron Gould [mailto:aaron1 at gvtc.com] 
Gesendet: Samstag, 12. August 2017 02:03
An: alexander.marhold at gmx.at; 'Vincent Bernat'; juniper-nsp at puck.nether.net
Betreff: RE: [j-nsp] Many contributing routes

I have a note during a jncis-sp study I did...

"generated routes receive the next hop of the primary contributing route.
primary contributing route is the route with lowest preference of all the
contributing routes falling within the aggregate range of prefixes.  if
there are multiple contributing routes with same preference, tie breaker is
LOWEST prefix number... NOT lowest prefix length."

Forgive me as I don't have much real-world experience with this topic, but
is this note above accurate ?

I'm wondering if he is getting lots of what appear to be ebgp learned
prefixes I'm thinking they would all be Preference 170, with all that being
tied at 170, would the tiebreaker go to the lowest prefix number ?  like
1.0.0.0 or 3.0.0.0 or something low like that ?

- Aaron Gould