Thanks Doug that seems to make sense.  I will give your gns3 topology a go

Sent from my iPhone

On 15/11/2012, at 11:36 PM, "[email protected]" <[email protected]> wrote:

> Actually, I mean the OSPF routes (originating from the remote customer
> site, advertised across the back-door link to the local CE, and then
> advertised to the local PE) have an AD of 110, while the BGP routes
> (advertised via OSPF from the remote site CE to the the remote PE, then
> redistributed into BGP and advertised to the local PE) have an AD of
> 200. So the PE selects the OSPF routes to insert into the VRF routing
> table, and the BGP routes never get re-distributed.
> 
> Here's a link to the GNS3 topology I'm using for this. Have a quick
> look, it will make much more sense than my rambling on...
> http://gns3vault.com/MPLS/advanced-mpls-vpn.html
> 
> Thanks,
> 
> Doug
> 
> 
> 
> 
> -------- Original Message --------
> Subject: Re: [OSL | CCIE_RS] OSPF behavior with MPLS VPN, backdoor
> link, no sham link
> From: Steve Storniak <[email protected]>
> Date: Thu, November 15, 2012 7:23 am
> To: "[email protected]" <[email protected]>, 
> "[email protected]" <[email protected]>
> 
> Did you mean local CE routes (internal) have high priority over BGP
> routes(external) per ospf route selection process?
> 
> 
> 
> Steve
> 
> 
>     From:  [email protected] <[email protected]>; 
>  To:  <[email protected]>; 
>  Subject:  Re: [OSL | CCIE_RS] OSPF behavior with MPLS VPN, backdoor
> link, no sham link 
>  Sent:  Thu, Nov 15, 2012 11:05:13 AM 
> 
>    Specifying the both external and internal types when re-distributing
> into MP-BGP doesn't seem to make a difference. Since they are all
> internal routes, the distribution works without specifying the route
> types, as evidenced by the Type 3 LSA's and O IA routes showing up when
> I shut down the back-door link.
> 
> But I think I have the answer... Here's an excerpt from "sh ip bgp vpnv4
> vrf MELON" from the PE router that connects to one customer site, let's
> call it "Customer Site A". This was taken while the back-door link was
> up:
> 
> *> 12.12.12.12/32  192.168.23.2          111        32768 ?
> * i                5.5.5.5                11    100      0 ?
> 
> And here an excerpt from "show ip route vrf MELON" for the same route:
> 
> O      12.12.12.12 [110/111] via 192.168.23.2, 00:00:04, Ethernet0/3
>    13.0.0.0/32 is subnetted, 1 subnets
> 
> 192.168.23.2 is the CE router at "Customer Site A", while 5.5.5.5 is the
> PE router loopback that connects to "Customer Site B" and 12.12.12.12 is
> the loopback of the CE router at "Customer Site B".
> 
> Only active routes, present in the VRF's routing table, are
> re-distributed. Since the OSPF routes from the local CE have a lower AD
> than the BGP routes from the other site, the OSPF routes are active in
> the VRF's routing table, not the BGP routes. So the BGP routes from the
> other site coming across the MPLS VPN never get redistributed into OSPF,
> so the LSA's don't get created.
> 
> Does this sound correct?
> 
> Doug
> 
> 
> 
> 
> -------- Original Message --------
> Subject: Re: [OSL | CCIE_RS] OSPF behavior with MPLS VPN, backdoor
> link, no sham link
> From: Greg Chisholm <[email protected]>
> Date: Wed, November 14, 2012 8:21 pm
> To: [email protected]
> 
> On 11/14/2012 05:12 PM, [email protected] wrote:
>> I'm working on a sham link lab, and came across some behavior I don't
>> understand. I've got the MPLS L3VPN built, and routes are being learned
>> across it properly. Everything is in area 0, and I've used the same
>> process ID for the vrf on both PE's. I do not have the sham link
>> configured yet, so all traffic is going over the back-door link.
>> 
>> The thing I don't understand is that there are no Type3 LSA's anywhere,
>> not on the CE routers, nor on the PE vrf's. I only see type 1 and Type 2
>> LSA's. If I shut down the back-door link, the Type 3's show up, along
>> with the O IA routes as expected.
>> 
>> I would think that while the back-door is up, we would see the Type 2
>> LSA's coming across the back-door link, as well as the Type 3 LSA's
>> being redistributed from MP-BGP.
>> 
>> What am I missing?
>> 
>> Thanks,
>> 
>> Doug
>> _______________________________________________
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> 
> Look at your redistribution in BGP, you need to specify the types of 
> OSPF routes with redistribute ospf
> _______________________________________________
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> please visit www.ipexpert.com
> 
> Are you a CCNP or CCIE and looking for a job? Check out
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> _______________________________________________
> For more information regarding industry leading CCIE Lab training,
> please visit www.ipexpert.com
> 
> Are you a CCNP or CCIE and looking for a job? Check out
> www.PlatinumPlacement.com
> 
> http://onlinestudylist.com/mailman/listinfo/ccie_rs
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please 
> visit www.ipexpert.com
> 
> Are you a CCNP or CCIE and looking for a job? Check out 
> www.PlatinumPlacement.com
> 
> http://onlinestudylist.com/mailman/listinfo/ccie_rs
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