[c-nsp] BGP Route Selection

[Oliver Boehmer (oboehmer)]

Andy Saykao <> wrote on Wednesday, March 11, 2009 04:30:

> Hi All,
> 
> Just trying to get my head around why BGP prefers a certain route over
> others in my example below. I've read up on how BGP makes it's path
> selection decision but I can't follow why it hasn't chosen a route
> with a higher local preferences.

because all the paths with a higher local-pref are ignored as they are
"received-only", i.e. stored in the table due to "soft-recoconfiguration
inbound" config on your neighbors..  
 
[..]
> 
> What's the relationship between the "sh ip bgp A.B.C.D" and "sh ip bgp
> longer-prefixes" command?

the latter only shows the non-received-only paths..

> Why are there "(received-only)" routes and
> what does that mean? The "(received-only)" routes have a higher local
> preferences but why aren't they shown with the "sh ip bgp
> longer-prefixes" command?

see above: because they are ignored.. this is also described in
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a008009
4431.shtml..

	oli