A system for efficient multicast control packet forwarding is provided. During operation, the system can maintain a first tunnel between a first switch and a second switch in an overlay tunnel fabric. The encapsulation of a packet sent via the overlay tunnel fabric is initiated and terminated within the overlay tunnel fabric. The system can maintain a second tunnel between the first switch and a third switch, which can be in an external network that excludes the first and second switches. The switch can distinguish the first and second tunnels as intra-fabric and inter-fabric tunnels, respectively. Upon receiving a multicast control packet via the first tunnel, the system can identify the second tunnel as the inter-fabric tunnel and forward the multicast control packet via the second tunnel. Here, a respective multicast control packet received from the first tunnel can be precluded from being forwarded on intra-fabric tunnels.