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Re: I Need a Rule posted 08/12/2000
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The reason is due to the Administrative distance of the various protocols.

Protocol    Administrative Distance
------------    ---------------------------------
EBGP        20
EIGRP       90
IGRP         100
RIP            120
IBGP          200

So when the router needs to choose which route to "believe" it will always
choose the route with the lowest administrative distance.  Since the IGP
protocols have a lower AD then IBGP, guess what protocols always win?

Your routes are being passed through IBGP and the various IGP protocols.  If
an IBGP speaker redistributes a route into the IGP table, then that route
will become the preferred route for all other IGP participants.  Therefore
when you type "show ip route" you will only see the IGP derived route, not
the IBGP route.

You can verify a route is being passed through IBGP by typing "show ip bgp"
or changing the Administrative Distance of the IBGP routes.  Also, play
around with creating BGP back-door routes.

Take care,


Paul Borghese


----- Original Message -----
From: "Kenneth R. Snell" <ksnell@xxxxxxxxxxxxx>
To: <ccielab@xxxxxxxxxxxxxx>
Sent: Friday, August 11, 2000 8:37 PM
Subject: I Need a Rule


> I'm trying to redistribute BGP routes into an IGP routing process (mainly
> RIP, EIGRP and IGRP). I can see EBGP routes but not IBGP routes. Now, I
can
> live with that but I need to know why? Anybody got a rule or reference I
can
> look up? Thanks
>
> _________________________
> Kenneth R. Snell
> Network Architect
> Syndicate Network Solutions
> _________________________
>
> _______________________________________________________
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