Re: RIP is preferred over eBGP! posted 09/27/2007
- Subject: Re: RIP is preferred over eBGP!
- From: Ben <bmunyao@xxxxxxxxx>
- Date: Thu, 27 Sep 2007 18:23:10 +0300
- Cc: "Cisco certification" <ccielab@xxxxxxxxxxxxxx>
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Step 1: Router B is faced with two BGP sources, ebgp and locally originated
(redistributed from RIP).
BGP decision process will pick the locally originated over the ebgp route
W - weight
L - local preference
L - locally originated
A - AS path
O - Origin
M - MED
N - Neighbor Type
I - cannot remember :)
Step 2: BGP administrative distance for locally originated is 200, for RIP
120. RIP therefore wins.
In case I've got the sequence figured out wrongly, comments are welcome.
On 9/26/07, Gregory Gombas <ggombas@xxxxxxxxx> wrote:
> I'm seeing the following quirk in a production network:
> Router A is directly connected to router B and is sending the same
> routes via RIP and eBGP.
> Router B is also redistributing the RIP routes into BGP (but filtered
> from sending back to A)
> When you look at the route table on RouterB, it shows the routes as RIP
> You would think the eBGP learned routes would be preferred because of
> lower AD.
> But when I look at BGP table it shows the route originated locally and
> thus preferred over eBGP learned route.
> When I clear ip route the route is then shown as a eBGP route in the
> routing table and BGP route table does not show the locally originated
> Just wondering if anyone else has seen this...
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