[j-nsp] leak routes between L3VPN VRF's

[tim tiriche]

Hello,

I am looking for a clean and simple way to leak routes between VRF's on the
same PE and across different PE?

For eg:  On PE1 and PE2, if i have 3 VRF's. (VRF1, VRF2, VRF3).  These are
mpls l3vpn vrf's.

How can i leak routes between VRF1 and VRF2 on the same PE and across PE

a) Can i do it only using RT (vrf-import)? or do i need to also implement
rib-groups?
b) can i do auto-export with policies on PE1 for exchanging routes only
between VRF1 and VRF2

I would like to avoid rib-groups if possible and looking for simplicity and
best practices around this.

-Tim