Mailing List Archive

CSCdx26714

1. Symptom :

If the prefix get Rib-Failre when installing into bgp table because of
there is already has a prefix in the routing table with a prefered admin
distance (like already learnd by ospf), then this prefix should not be
advertised to other bgp peers unless the next-hop is the same as the
prefix
in the ip routing table.
But the behavior is that even if the next-hop is the same, this
prefix still
does not advertise to it's bgp peers.

2. Conditions :

You should see the bgp prefix get a "Rib-Failure" in the output of
"show ip bgp <x.x.x.x> ". This will confirm that this prefix fails to
install into the routing table. Then check the next-hop for the bgp
prefix
and the prefix that already in the ip table (it's ospf in this ddts). If
they are the same, then bgp should still advertise this prfix to it's bgp
peers.

3. Workaround :

Thers is not workaround for this problem.



Ezequiel Carson wrote:
> Hello,
>
>
> Have you seen this message on sh ip bgp ??
>
>
> Paths: (1 available, best #1, RIB-failure(17))
>
> R2#sh ip bgp 10.0.0.0
> BGP routing table entry for 10.0.0.0/24, version 8
> Paths: (1 available, best #1, RIB-failure(17))
> Multipath: iBGP
> Not advertised to any peer
> Local
> 192.168.0.1 from 192.168.0.1 (192.168.0.1)
> Origin IGP, metric 0, localpref 100, valid, internal, best
> R2#
>
>
> Im running IOS 12.2(8)T5 , it ocurrs when a route is learned via OSPF
> and BGP. OSPF wins,but BGP invalidates this prefix from his RIB and it
> is on allowed to advertised to any peer.
>
>
> Any suggestion?
>
> Comment: This is not happening with another version like 12.0(21)ST.
>
>
> Thanks
> Ezequiel
>
> _______________________________________________
> cisco-nsp mailing list real_name)s@puck.nether.net
> http://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>

This bug is fixed in 12.2.10T ... I'm waiting for the release to come
(I think it will be at the end of this month).


> CSCdx26714
>
> 1. Symptom :
>
> If the prefix get Rib-Failre when installing into bgp table because of
> there is already has a prefix in the routing table with a prefered admin
> distance (like already learnd by ospf), then this prefix should not be
> advertised to other bgp peers unless the next-hop is the same as the
> prefix
> in the ip routing table.
> But the behavior is that even if the next-hop is the same, this
> prefix still
> does not advertise to it's bgp peers.
>
> 2. Conditions :
>
> You should see the bgp prefix get a "Rib-Failure" in the output of
> "show ip bgp <x.x.x.x> ". This will confirm that this prefix fails to
> install into the routing table. Then check the next-hop for the bgp
> prefix
> and the prefix that already in the ip table (it's ospf in this ddts). If
> they are the same, then bgp should still advertise this prfix to it's bgp
> peers.
>
> 3. Workaround :
>
> Thers is not workaround for this problem.
>
>
>
> Ezequiel Carson wrote:
> > Hello,
> >
> >
> > Have you seen this message on sh ip bgp ??
> >
> >
> > Paths: (1 available, best #1, RIB-failure(17))
> >
> > R2#sh ip bgp 10.0.0.0
> > BGP routing table entry for 10.0.0.0/24, version 8
> > Paths: (1 available, best #1, RIB-failure(17))
> > Multipath: iBGP
> > Not advertised to any peer
> > Local
> > 192.168.0.1 from 192.168.0.1 (192.168.0.1)
> > Origin IGP, metric 0, localpref 100, valid, internal, best
> > R2#
> >
> >
> > Im running IOS 12.2(8)T5 , it ocurrs when a route is learned via OSPF
> > and BGP. OSPF wins,but BGP invalidates this prefix from his RIB and it
> > is on allowed to advertised to any peer.
> >
> >
> > Any suggestion?
> >
> > Comment: This is not happening with another version like 12.0(21)ST.
> >
> >
> > Thanks
> > Ezequiel
> >
> > _______________________________________________
> > cisco-nsp mailing list real_name)s@puck.nether.net
> > http://puck.nether.net/mailman/listinfo/cisco-nsp
> > archive at http://puck.nether.net/pipermail/cisco-nsp/
> >
>
>
> _______________________________________________
> cisco-nsp mailing list real_name)s@puck.nether.net
> http://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>

--

George Boulescu
Senior Network Engineer
RoEduNet Bucharest NOC
CCAI, CCNA