Hey all. I am trying to configured VRF-lite in a Dynamips environment using four 3640 routers (topology is shown in the attached .jpg). For some reason I am just not grasping the concepts behind VRF in general. I have been scouring the Internet for references all day (literally all day) to try and find a blog or a white paper that can "flip the switch" so to speak and get me over the hump. One of the areas that I'm REALLY struggling in is with the idea of RD and RT's. Is the RD globally unique or not?? For the RT's, I see some configs that have both the export and import set as the same ASN:nn but in some others I see the export = the local RD and the import = a neighbors export RT. For example:
ip vrf rtr1vrf
route-target export 64512:01
route-target import 64515:01
ip vrf rtr2vrf
route-target export 64515:01
route-target import 64512:01
How and why would you set the export and import to be the same?? When I do a sho ip bgp or a show ip bgp neighbor I just get blank lines back, why is that?? I am peering successfully. One last question is in my scenario I don't want Clutterbuck and Burns to know about each other, but I want Koivu to know about both of them. I thought that I could just configure Clutterbuck and Burns to import routes from 1001:2 and they would only see the routes sourced from Koivu. Do only routes sourced by Koivu get the 1001:2 extended community value?? Do I need to have a distribute-list in place instead?? It just doesn't make sense. Please give me a swift kick in the skull...
my first answer is misleading because it is focused on MPLS VPN.
With VRF-lite there is no VPNv4 address-family and you have eBGP sessions in address family vrf.
to be noted that this should be normal eBGP sessions, that is I don't expect that the job you did on route targets that is already similar to what I called hub and spoke is effective.
you are using send-community both but this should not allow to pass route targets.
in your case you should use route-maps like in a classic scenario to filter routes sent to each device.
let me say in real world VRF lite is not used in this way.
In a scenario like yours is more common to use full L3 MPLS VPN.
in that case central router can act as P node and Route reflector server and it is possible to implement an hub and spoke topology playing on route targets.
VRF lite is used with multilayer switches to act as multi-VRF CE nodes shared by different customers.
Hope to help