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Cisco BGP Case Study #5 - Simple Question

Hello all - I'm missing something here - but I'll ask anyway... :)

Take a look at the BGP Case Studies (Case#5, Practical Design

Example) at:

Watch the wrap.

http://www.cisco.com/en/US/tech/tk648/tk365/technologies_tech_note09186a00800c95bb.shtml#example

In the beginning of the case study, I am assuming synchronization is on

as the author asks us to turn it off in the next few pages.

My issue: Take a look at the first "show ip bgp" for RTB in case study #5.

Notice this network:

Network Next Hop Metric LocPrf Weight Path

*>i203.250.13.0 203.250.13.41 0 100 0 i

Given that this route is learned via iBGP and we see the > notation, doesn't this suggest that the route is synchronized with an IGP route?

Yet, since this is an ospf route originating from a loopback interface

from RTA, it will be advertised as a /32 in OSPF.

This is where I get confused. Can BGP report that a route is

synchronized, best and valid if there isn't a corresponding route with

the exact same prefix in the IGP table assuming synchronization is on?

Am I missing something here?

TIA!

Scott

1 REPLY
Community Member

Re: Cisco BGP Case Study #5 - Simple Question

Hi Scott,

I am not sure if the problem still exists, but because it is not yet unswered I try to give you a hint: look at the Loopback interface mask - it is 24 bits long. I think this is why everything, what is written (concerning your doubts) should work.

If you already solved it, then forgive my late reaction.

Regards

Adam

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