Map the SCU-Enabled vt Interface to the VRF Instance

Next, include the VPN loopback tunnel interface in the desired VRF instance at the [edit routing-instances routing-instance-name] hierarchy level:

[edit]

routing-instances {

    routing-instance-name {

        instance-type vrf;

        interface at-2/1/1.0;

        interface vt-0/3/0.0;

        route-distinguisher 10.250.14.225:100;

        vrf-import import-policy-name;

        vrf-export export-policy-name;

        protocols {

            bgp {

                group to-r4 {

                    local-address 10.20.253.1;

                    peer-as 400;

                    neighbor 10.20.253.2;

                }

            } 

        }

    }

}