How many Layer 2 circuits can be terminated into a single VRF instance?
On an MX Series router, 48 Layer 2 circuits can be terminated into a single VRF, per each tunnel PIC.
The limiting factor is the way MAC addresses are assigned to logical tunnel (lt) interface units. On an MX Series router, there are 1984 MAC addresses on the EEPROM. This is statically divided by the number of slots (12) and PICs (4) to determine there are 48 per PIC. That number is the same on each platform although MAC space might be smaller.
Additional limitations are presented by the availability of bandwidth and the lack of resiliency because these solutions are bound to a tunnel PIC. If the dense port concentrator (DPC) associated with the tunnel goes down, all Layer 2 circuits are gone.
For more information, click Layer 2 VPNs and VPLS Feature Guide.