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New Member

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.

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 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?



ps - Sorry to ask this questions again.

New Member

Re: Cisco BGP Case Study #5 - Simple Question

No bgp can not send out a route that is not nailed down. It can summarize a route with others

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