I have a couple of 5 loopbacks on the same router. 1 in one VRF A and the other 4 in VRF B. They need to talk to each other WITHOUT using the import/export of RT's. Would appreciate any help on this.
You can use EVN (Easy Virtual Network).
Under the vrf definition you have to configure route-replicate:
vrf def A
ad ipv4 uni
route-replicate from vrf B
vrf def B
route-replicate from vrf A
If you want to advertise the prefixes B with the IGP of A you have to use redistribution from the VRF.
router ospf 10 vrf A
redistribute vrf B ospf 20
For BGP it does not work and you have to use another solution like RT's or multiple peerings.
more info at http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/evn/configuration/xe-3s/evn-xe-3s-book/evn-shared-svcs.html
Thanks a lot Marten. So, if I do not redistribute, then these loopbacks can talk to each other only? My target is not have all the routes in each VRF talk to each other. ONLY these loopbacks to talk to each other which are in different VRF. Would it still apply?
In that case only route-replicate would be enough and you can use a route-map to filter the specific interfaces.