Re: BGP backdoor

This is just a shot in the dark but looking at your configuration...

On CE7, why are you advertising this:

network 10.5.8.0 mask 255.255.255.0 backdoor

On CE8, why are you advertising this:

network 10.5.7.0 mask 255.255.255.0 backdoor

What I think you are missing is that you cant add the "backdoor" command to a network that someone else is advertising.

The network "10.5.7.0" is on CE7, but you have the backdoor command on CE8. The same for the other CE router.

I could be wrong and I am sure that if I am that it will be pointed out more than once!

HTHs

On Sep 3, 2010, at 11:45 AM, Carlos G Mendioroz wrote:

> Srinivas,
> the AD of the route that is there is 20, so the problem seems to be that
> backdoor is not kicking in.
>
> srinivas pv @ 3/9/2010 9:38 -0300 dixit:
>> Hi,
>> I think CE routes are not getting propagated through RIP. Could you try
>> shutting down interfaces between CE and PE, so that you should see routes
>> through RIP.
>> Thanks,
>> Srinivas
>> On Fri, Sep 3, 2010 at 11:09 AM, selamat pagi <ketimun_at_gmail.com> wrote:
>>> Trying to understand the usage of backdoor command in BGP.
>>>
>>> This is my Lab-setup. With the neigbors-loopbacks configured as backdoor,
>>> I
>>> would expect to see CE7 lo on CE8 as a RIP-route.
>>> But I still get the eBGP route vie PE.
>>>
>>> ------------------------------------RIP ----------------------------------
>>> |
>>> |
>>> CE7 -- eBGP --- PE2 --- MPLS --- PE5 -- eBGP -- CE8
>>>
>>>
>>> CE7
>>> interface Loopback0
>>> ip address 10.5.7.7 255.255.255.0
>>>
>>> router bgp 200
>>> no synchronization
>>> bgp router-id 10.5.7.7
>>> bgp log-neighbor-changes
>>> network 10.5.7.0 mask 255.255.255.0
>>> network 10.5.8.0 mask 255.255.255.0 backdoor
>>> neighbor 10.5.27.2 remote-as 100
>>> neighbor 10.5.27.2 allowas-in
>>>
>>>
>>> CE8
>>> interface Loopback0
>>> ip address 10.5.8.8 255.255.255.0
>>>
>>> router bgp 200
>>> bgp router-id 10.5.8.8
>>> network 10.5.7.0 mask 255.255.255.0 backdoor
>>> network 10.5.8.0 mask 255.255.255.0
>>> neighbor 10.5.58.5 remote-as 100
>>> neighbor 10.5.58.5 allowas-in
>>>
>>>
>>> R8#sh ip route
>>> 158.5.0.0/32 is subnetted, 1 subnets
>>> B 158.5.6.6 [20/0] via 10.5.58.5, 14:53:51
>>> 10.0.0.0/24 is subnetted, 5 subnets
>>> C 10.5.8.0 is directly connected, Loopback0
>>> B 10.5.7.0 [20/0] via 10.5.58.5, 00:00:06 <-- would expect to
>>> get this via RIP
>>> R 10.5.27.0 [120/1] via 10.5.78.7, 00:00:18, Vlan78
>>> C 10.5.58.0 is directly connected, Vlan58
>>> C 10.5.78.0 is directly connected, Vlan78
>>>
>>>
>>> What do I miss here ?
>>>
>>> Thanks, keti
>>>
>>>
>>>
>>>
>>> http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a00800c95bb.shtml#bgpbackdoor
>>>
>>>
>>> Blogs and organic groups at http://www.ccie.net
>>>
>>> _______________________________________________________________________
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>
> --
> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
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Received on Fri Sep 03 2010 - 14:44:57 ART