Hi,
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In Cisco device, my understanding is two vrf route-targe exchange so that the traffic can pass the two vrf
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AFAIK, in Cisco 2 vrfs exchange routes by default if the required route-targets are being imported.
In Juniper "auto-export" needs to be enabled on the participating vrfs for the route exchange between them:
set routing-instances xxx routing-options auto-export
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Based on Cisco device, we need to know what is global vrf value?
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I am not sure there is any route-target [vrf value] for the global unicast routing table even on Cisco or Juniper. Please share if you have some info on this.
There is a caveat with scenario 2 [vrf MP-BGP l3vpn routes to inet.0] using rib-groups. Rib-groups can export PE-CE routes from the vrf to inet.0, but not MP-BGP l3vpn routes learnt from a remote PE. This is because of different BGP address families.
To export vrf l3vpn routes to inet.0, you could use the lt interface to bridge the vrf to inet.0.
How are the routes being learnt on R2 from R3. Is that over an MPLS L3VPN PE-PE?
Could you share your sample configs to have a better understanding.
Cheers,
Ashvin