OK, picture this from a BGP routing perspective:
ISP provides internet link to one of my PE's. This internet link has to service multiple customer VRF's. I have a Internet VRF configured which imports to each customer VRF for the default route, and the customer vrf's in turn export to teh Internet VRF their specific routing table. All works fine. All PE's use route reflectors for routing.
Now complexity is added. A second Internet site is provisioned which connects to a geographically differnet PE. This PE also uses the same Route reflectors etc. Of the multiple VRF's, I need one of them to prefer the internet link out of City #1, and the others to use the internet link out of City #2. Each should provide dynamic failover for one another.
Now in a simple world, local preference could do the trick. But a typical config on the PE for a customer VRF could be as follows, remember the bgp peering is done on a different vrf, and this vrf just imports the default route and then advertises it so there is no peer as such to add a route-map with local pref setting etc:
address-family ipv4 vrf customerABC
maximum-paths ibgp unequal-cost 2 import 4
Basically with the above config, how can I add in a more preferred or less preferred default route from one of two sites on a per vrf basis ?