Systems, methods, and non-transitory computer-readable storage media for a miscabling detection protocol. One or more switches can periodically send miscabling protocol (MCP) packets on non-fabric ports on all configured EPG VLANs. A first switch located at a network fabric receives a miscabling protocol (MCP) packet indicating an identity of an originating switch and a port number of an originating port of the MCP packet via a receiving port on the first switch, wherein the MCP packet is received from an external network connected to the receiving port, and wherein the originating switch and originating port are also located at the network fabric and connected to the external network. Based on the MCP packet, the first switch then detects a loop between the receiving port, the originating port, and the external network. Next, the first switch blocks the receiving port or the originating port in response to detecting the loop.