[j-nsp] Looking for ideas to configure hub and spoke vpn on the same PE.

[Pedro Roque Marques]

Joseph Lin wrote:
> All,
> 
> Its been about 2 years since I visited this subject, and am curious to know
> if anyone has came up with any new to configure this.
> 
> Here's the sample topology.
> 
> spoke#2
> |
> |
> Hub -- PE ----------------- PE ---------spoke#3
> |
> |
> spoke#1
> 
> The main problem I had was how to force spoke#1,spoke#2 to route thru the
> Hub's since they are on the same PE.
> 
> There were talks of mechanisms for inter-vrf routing, or using egress
> filtering.
> 
> Can anyone hand me a clue??
> 

Joseph,
You will need a hub and spoke VRF in the PE which is attached to the 
hub. i.e. hub VRF exports "target:<hub>" routes and imports 
"target:<spoke>" routes and vice-versa.

Don't forget to enable auto-export on those VRFs.

If you do have vrf-table-label enabled on the hub VRF you will need to 
get a bit fancier and do something like this:

Example w/ RIP as the PE-CE protocol torwards the hub.

routing-instances {
     hub {
         instance-type vrf;
         interface so-1/0/1.0;
         route-distinguisher 10.255.245.51:2;
         vrf-export hub_export_reject;
         vrf-target import target:10458:1;
         routing-options {
             interface-routes {
                 rib-group inet hub-rg;
             }
         }
         protocols {
             rip {
                 rib-group hub-rg;
                 group pe-ce {
                     export rip_advertise;
                     neighbor so-1/0/1.0;
                 }
             }
         }
     }
     hub_downstream {
         instance-type vrf;
         route-distinguisher 10.255.245.51:1;
         vrf-target target:10458:2;
         vrf-table-label;
     }
}
routing-options {
     rib-groups {
         hub-rg {
             import-rib [ hub.inet.0 hub_downstream.inet.0 ];
         }
     }
     autonomous-system 10458;
}
policy-options {
     policy-statement hub_export_reject {
         then {
             community add hub_target;
             reject;
         }
     }
     policy-statement rip_advertise {
         term a {
             from protocol bgp;
             then accept;
         }
         then reject;
     }
     community hub_target members target:10458:2;
     community spoke_target members target:10458:1;
}