BGP RIB-failure ::/0

[sebastien3]

Hello,

I have 3 routers that use BGP (Internal/External) + EIGRP for IGP.

Here is the quick configuration of routers :

-- R1 (fd12:3456:789a:1::1)

ipv6 route ::/0 Null0

router bgp 100
address-family ipv6
network ::/0

R1#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Backup from "eigrp 10 [170]"
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0
Last updated 1w0d ago

-- R2 (fd12:3456:789a:1::2)

ipv6 route ::/0 Null0

router bgp 100
address-family ipv6
network ::/0

R2#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Backup from "eigrp 10 [170]"
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0
Last updated 1w0d ago

-- R3 (fd12:3456:789a:1::3)

ipv6 route ::/0 Null0

router bgp 100
address-family ipv6
network ::/0

R3#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Backup from "bgp 100 [200]"
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0
Last updated 2d01h ago

R3#sh bgp ipv6 uni rib-failure
Network Next Hop RIB-failure RIB-NH Matches
::/0 fd12:3456:789a:1::1
IPv6 Higher admin distanc n/a

Only one router the R3 has a rib-failure. The difference compared to R1 and R2 is that it knows ::/0 by BGP instead of EIGRP like the others.
I don't understand why because the configuration of the 3 routers is identical

An idea ?

[sebastien3]

Here is the BGP config of R3.

>You might want to try removing the network statement and re-apply it.
I have already tried to remove and put back network ::/0 from BGP but that does not change anything.

R3#show run | sec router bgp
router bgp 100
bgp router-id 10.0.0.3
no bgp enforce-first-as
bgp log-neighbor-changes
bgp graceful-restart restart-time 120
bgp graceful-restart stalepath-time 360
bgp graceful-restart
neighbor iBGP-V4 peer-group
neighbor iBGP-V4 remote-as 100
neighbor iBGP-V6 peer-group
neighbor iBGP-V6 remote-as 100
neighbor iBGP-V6 update-source Loopback1
neighbor 10.0.0.1 peer-group iBGP-V4
neighbor 10.0.0.1 description R1
neighbor 10.0.0.2 peer-group iBGP-V4
neighbor 10.0.0.2 description R2
neighbor 10.0.0.4 peer-group iBGP-V4
neighbor 10.0.0.4 description R4
neighbor 2600:7000:x:x::x:1 remote-as 6939
neighbor 2600:7000:x:x::x:1 description * Fullview V6 *
neighbor 66.160.X.X remote-as 6939
neighbor 66.160.X.X description * Fullview V4 *
neighbor 66.160.X.X shutdown
neighbor fd12:3456:789a:1::1 peer-group iBGP-V6
neighbor fd12:3456:789a:1::1 description R1
neighbor fd12:3456:789a:1::2 peer-group iBGP-V6
neighbor fd12:3456:789a:1::2 description R2
neighbor fd12:3456:789a:1::4 peer-group iBGP-V6
neighbor fd12:3456:789a:1::4 description R4
!
address-family ipv4
network X.X.X.0 mask 255.255.255.0
neighbor iBGP-V4 next-hop-self
neighbor iBGP-V4 soft-reconfiguration inbound
neighbor 10.0.0.1 activate
neighbor 10.0.0.2 activate
neighbor 10.0.0.4 activate
no neighbor 2600:7000:x:x::x:1 activate
neighbor 66.160.X.X activate
neighbor 66.160.X.X soft-reconfiguration inbound
neighbor 66.160.X.X prefix-list HE_OUT_V4 out
neighbor 66.160.X.X route-map HE_IN_V4 in
neighbor 66.160.X.X filter-list 2 in
neighbor 66.160.X.X filter-list 1 out
no neighbor fd12:3456:789a:1::1 activate
no neighbor fd12:3456:789a:1::4 activate
no neighbor fd12:3456:789a:1::2 activate
exit-address-family
!
address-family ipv6
network ::/0
network 2001:X:X::/48
neighbor iBGP-V6 next-hop-self
neighbor iBGP-V6 soft-reconfiguration inbound
neighbor 2600:7000:x:x::x:1 activate
neighbor 2600:7000:x:x::x:1 send-community
neighbor 2600:7000:x:x::x:1 weight 50
neighbor 2600:7000:x:x::x:1 soft-reconfiguration inbound
neighbor 2600:7000:x:x::x:1 route-map HE_IN_V6 in
neighbor 2600:7000:x:x::x:1 route-map HE_OUT_V6 out
neighbor 2600:7000:x:x::x:1 filter-list 2 in
neighbor 2600:7000:x:x::x:1 filter-list 1 out
neighbor fd12:3456:789a:1::1 activate
neighbor fd12:3456:789a:1::4 activate
neighbor fd12:3456:789a:1::2 activate
exit-address-family

[sebastien3]

I completely deleted the BGP configuration and recreated it on R3 ! Now I have no more rib-failure. A IOS big bug ??

R1#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Backup from "eigrp 10 [170]"
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0

R2#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Backup from "eigrp 10 [170]"
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0

R3#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0

Why does R3 have no backup via eigrp 10 ?

[MHM Cisco World]

I run lab yesterday' but I want to ask are eigrp is

redistrubte static route or redistrubte bgp

?

[Harold Ritter · Accepted solution]

Hi @sebastien3 ,

The state on R3 is actually the proper state. You should see the same on R1 and R2 as well. Do a

clear ipv6 route ::/0

on both R1 and R2. This should remove the backup from eigrp on R1 and R2.

[sebastien3]

You are right @Harold Ritter ! Thanks !

R1/R2/R3 have the same routing entry :

#sh ipv6 route ::/0
Routing entry for ::/0
Known via "static", distance 1, metric 0
Route count is 1/1, share count 0
Routing paths:
directly connected via Null0
Last updated 00:00:11 ago

A question ! Should have the same for IPV4 ? I just compared and I don't have the same thing... 0.0.0.0/0 is advertised by BGP...

R1#sh ip route 0.0.0.0 0.0.0.0
Routing entry for 0.0.0.0/0, supernet
Known via "static", distance 1, metric 0 (connected), candidate default path
Advertised by bgp 100
Routing Descriptor Blocks:
* directly connected, via Null0
Route metric is 0, traffic share count is 1

[Harold Ritter]

@sebastien3 ,

It appears indeed that the output you get for ipv4 is different than what you get for ipv6. The

show ipv6 route ::/0

doesn't explicitly say that the prefix is advertised by BGP, although it is in this case. 

Regards,

[sebastien3]

@Harold Ritter Ok so there is no problem here between EIGRP and BGP for IPV4 and IPV6, all seems correct to you ?

It's just a different display between the V4 and V6 version, right ?

Thanks

[Harold Ritter]

Hi @sebastien3 ,

> It's just a different display between the V4 and V6 version, right ?

That is correct.

Regards,

[sebastien3]

@MHM Cisco World EIGRP is configured the same way on R1/R2/R3 routers using common VLAN 11. Here is the R3 config :

router eigrp V6
!
address-family ipv6 unicast autonomous-system 10
!
af-interface default
passive-interface
exit-af-interface
!
af-interface TenGigabitEthernet0/1/0.10
authentication mode md5
authentication key-chain EIGRP_KEY
bfd
no passive-interface
exit-af-interface
!
af-interface TenGigabitEthernet0/3/0.11
authentication mode md5
authentication key-chain EIGRP_KEY
bfd
no passive-interface
exit-af-interface
!
topology base
exit-af-topology
eigrp router-id 10.0.0.3
nsf
exit-address-family

[MHM Cisco World]

First sorry but I have multi issue I must handle in same time'

Now' the rib failure I dent get solution for it wit

Eigrp and bgp' and high metric appear in

show ip bgp

and behave for ipv4 and ipv6

All this happened because you run ibgp and use LO as update source and this update source learn from eigrp.

[sebastien3]

@MHM Cisco World: No problem, don't worry

>All this happened because you run ibgp and use LO as update source and this update source learn from eigrp.

Yes I use update-source lo0 in iBGP conf. But I can't really understand why I had to delete the configuration from R3 then do a clear ipv6 route to get it back to normal...

[MHM Cisco World]

sorry @sebastien3  what is LO you use as Update source in each router ?

[sebastien3]

Yes I use an LO1 on each router.

2001X:XX::1/128 for R1 2001X:XX::2/128 for R2
2001X:XX::3/128 for R3

Do you see a problem there ?