RE: MPLS BGP problem

Here you go

Good router

              r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path

Route Distinguisher: 65000:1009 (default for vrf test)

*>i0.0.0.0 192.168.151.117 1 100 0 65495 i

* i10.238.163.128/26 192.168.151.129 2 100 0 65529 i

*> 10.238.165.121 2 0 65529 i

* i10.238.165.96/27 192.168.151.129 0 100 0 65529 i

*> 10.238.165.121 0 0 65529 i

Bad router

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network Next Hop Metric LocPrf Weight Path

Route Distinguisher: 65000:1009 (default for vrf test)

*> 10.238.163.128/26

                    10.238.165.125 2 0 65529 i

* i 192.168.151.128 2 100 0 65529 i

*> 10.238.165.96/27 10.238.165.125 0 0 65529 i

* i 192.168.151.128 0 100 0 65529 i

But is the route not being installed due to lack of cef next hop?

If ip split the default in to two halves 128.0.0..0/1 and 0.0.0.0/1 it works OK on both routers.

From: Marcin PolaEski [mailto:mcinus_at_gmail.com]
Sent: 27 November 2009 12:01
To: Ryder, Keith
Subject: Re: MPLS BGP problem

Keith

Show us sh ip bgp vpnv4 vrf test
Maybe your 0.0.0.0 doesn't have next hop in routing table

Best
Marcin

On Fri, Nov 27, 2009 at 12:14 PM, Ryder, Keith <Keith.Ryder_at_globalcrossing.com> wrote:

I have a working MPLS network but when a new VRF is added one router
refuses to install the default received from an Ebgp peer.

Below is the simple part if the VRF config

ip vrf test

rd 60000:1009

route-target export 60000:1009

route-target import 60000:1009

router bgp 60000

neighbor etc etc

address-family ipv4 vrf test

neighbor 10.238.165.125 remote-as 60000

neighbor 10.238.165.125 version 4

neighbor 10.238.165.125 activate

neighbor 10.238.165.125 send-community

no auto-summary

no synchronization

exit-address-family

routes in the vrf look fine

Show ip route vrf test

1.0.0.0/32 is subnetted, 1 subnets

B 1.1.1.1 [200/0] via 192.168.151.117, 00:30:02

10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks

B 10.238.165.96/27 [20/0] via 10.238.165.125, 22:39:07

C 10.238.128.0/18 is directly connected, FastEthernet2/5.938

B 10.238.163.128/26 [20/2] via 10.238.165.125, 22:43:23

But no default route installed.

CEF shows

Prefix Next Hop Interface

0.0.0.0/0 drop Null0 (default route handler
entry)

0.0.0.0/32 receive

1.1.1.1/32 192.168.151.7 SRP1/1

10.238.128.0/18 attached FastEthernet2/5.938

10.238.128.0/32 receive

10.238.163.128/26 10.238.165.125 FastEthernet2/5.938

10.238.165.96/27 10.238.165.125 FastEthernet2/5.938

10.238.165.125/32 10.238.165.125 FastEthernet2/5.938

Same config on another router (all connected via an srp ring)

1.0.0.0/32 is subnetted, 1 subnets

B 1.1.1.1 [200/0] via 192.168.151.117, 00:32:29

10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks

B 10.238.165.96/27 [20/0] via 10.238.165.121, 5w1d

C 10.238.165.120/30 is directly connected, FastEthernet2/5.937

B 10.238.163.128/26 [20/2] via 10.238.165.121, 5w1d

B* 0.0.0.0/0 [200/1] via 192.168.151.117, 21:10:25

Default route installed.

CEF shows

Prefix Next Hop Interface

0.0.0.0/0 192.168.151.7 SRP1/1

0.0.0.0/32 receive

1.1.1.1/32 192.168.151.7 SRP1/1

10.238.163.128/26 10.238.165.121 FastEthernet2/5.937

10.238.165.96/27 10.238.165.121 FastEthernet2/5.937

10.238.165.120/30 attached FastEthernet2/5.937

10.238.165.120/32 receive

10.238.165.121/32 10.238.165.121 FastEthernet2/5.937

10.238.165.122/32 receive

10.238.165.123/32 receive

224.0.0.0/24 receive

255.255.255.255/32 receive

I can force a route to be advertised as I have done with 1.1.1.1 using a
null route.

Is the default route not being installed due to the cef drop or
something else?

Driving me nuts everything works but not a default route.

FE-----Router 1----SRP 1/1------Router2------FE------Router3(origin of
1.1.1.1-------R4(origin of 0.0.0.0)

Default OK No default
<<<<0.0.0.0

1.1.1.1 ok 1.1.1.1 ok

Blogs and organic groups at http://www.ccie.net
Received on Fri Nov 27 2009 - 13:13:58 ART