From: Carlos Alberto Trujillo Jimenez (carlos.trujillo.jimenez@gmail.com)
Date: Fri Mar 07 2008 - 14:17:45 ARST
Jorge, it is not correct.
If you have routes in the BGP table under RIB-failure, those router are
ADVERTISED to is peer routers via bgp.
In my example router 2 and router 5 are peering via bgp.
Router 2 has the "RIB-FAILURE" for the prefix 7.7.7.0/24 because the same
prefix via learned via ospf.
r2#show ip bgp
BGP table version is 1309, local router ID is 172.16.102.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 0.0.0.0 172.16.10.4 0 100 0 (65000) 700 i
r> 7.7.7.0/24 172.16.10.4 0 100 0 (65000) 700 i
r2#show ip route ospf
O E2 7.7.7.0 [110/1] via 172.16.10.4, 03:54:12, Serial0/0/0
Now you form an EBGP-PEERING between router and and router 5 and check the
bgp table of router 5 to see if it is learning via bgp the prefix 7.7.7.0.
r5#show ip bgp
BGP table version is 3, local router ID is 172.16.105.1
Status codes: s suppressed, d damped, h history, * valid, > best, i -
internal,
r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete
Network Next Hop Metric LocPrf Weight Path
*> 7.7.7.0/24 172.16.25.2 0 100 700 i
The prefix is present.
2008/3/7, Vazquez, Jorge <Jorge.Vazquez@acs-inc.com>:
>
> But, I think if you have some routes in the BGP table under RIB-failure,
> those routes are not advertised to the neighbors. So you may not have full
> reachability.
>
>
>
> *Jorge*
> ------------------------------
>
> *From:* Carlos Alberto Trujillo Jimenez [mailto:
> carlos.trujillo.jimenez@gmail.com]
> *Sent:* Friday, March 07, 2008 6:52 AM
> *To:* Vazquez, Jorge
> *Cc:* ccie forum
> *Subject:* Re: BGP Table on the Lab Exam
>
>
>
> Jorge.
>
>
>
> Adding one more thing.
>
>
>
> The presence of a rib-failure and the removing of that, depends of what is
> asked to do in the question.
>
>
>
> If the question states FULL REACHABILITY with rib-failure works fine.
>
> but if the question states PRESENT IN THE ROUTING TABLE VIA BGP. You may
> adjust some configurations as stated in my last mail, to let it work.
>
>
>
> 2008/3/7, Carlos Alberto Trujillo Jimenez <
> carlos.trujillo.jimenez@gmail.com>:
>
> Hi Jorge.
>
>
>
> A Rib Failure happens when a prefix is present in the bgp table, as well
> as in the routing, means the router recibes the same prefix via IBGP as well
> as ANY IGP (OSPF, RIP, EIGRP).
>
> According to the administrative distance ANY IGP is prefered over any IBGP
> ROUTE. Thats why the route is still present in the routing table, but
> learned via any of the IGP you are using in your network.
>
>
>
> If you have a RIB-FAILURE you can test it and it must work fine, you must
> have reachability to that prefix.
>
>
>
> From the BGP point of view, that route present in the bgp table (as
> RIB-FAILURE) is still propagated via bgp to its neighbors.
>
>
>
> if you want to remove the RIB-FAILURE in your bgp table you may adjust the
> ADMIN DISTANCE of the IGP to be higher than the IBGP or may REDUCE the IBGP
> admin distance to be lower than the IGP.
>
>
>
>
>
>
> cheers.
>
>
> 2008/3/7, Vazquez, Jorge <Jorge.Vazquez@acs-inc.com>:
>
> Any advice or comment about this? I would like to know what is correct
> solution when a RIB-failure appears, cause trying to fix that may impact
> the
> routing in all the network topology and maybe it may not be necessary.
>
>
>
> Jorge
>
> _____
>
> From: Vazquez, Jorge
> Sent: Thursday, March 06, 2008 10:29 AM
> To: ccie forum
> Subject: BGP Table on the Lab Exam
>
>
>
> I have completed some IE labs in the last days, I have one question about
> the BPG table, in case I get some routes with RIB-failure, do I have to
> fix
> that or is that ok to have some routes on RIB-failure?
>
>
>
> Regards,
>
>
>
> Jorge
>
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