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 > _______________________________________________ > 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 Look at your redistribution in BGP, you need to specify the types of OSPF routes with redistribute ospf _______________________________________________ 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 _______________________________________________ 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
