VRF Communication and Route Target Configuration

In MPLS VPN environments, communication between customer sites in different VRFs depends on the correct configuration of import and export route targets (RTs). For two VRFs to exchange routes and enable communication:

  1. The export RT of one VRF must match the import RT of the other VRF.
  2. This configuration is done on the Provider Edge (PE) routers only.
  3. Customer Edge (CE) routers are unaware of VRF and RT configurations.

For example, if VRF A exports RT 1:1, VRF B must import RT 1:1 for them to communicate. This principle applies to all VRF-to-VRF communications across the MPLS network. Proper RT configuration is crucial for controlling route distribution and enabling or restricting communication between different customer sites in an MPLS VPN setup.

https://networklessons.com/mpls/mpls-layer-3-vpn-configuration