A method for forwarding a multicast data packet, wherein, the method comprising: receiving, by an I/O board of an Virtual eXtensible Local Area Network, VXLAN, switch, a multicast data packet from a Virtual Local Area Network, VLAN; searching, by the I/O board, a local layer 3 multicast group table for a layer 3 multicast group entry matching with a destination Internet Protocol, IP, address and a destination Media Access Control, MAC, address of the multicast data packet; when at least one multicast group member port in the layer 3 multicast group entry corresponding to the multicast data packet is a first virtual port, sending the multicast data packet to a fabric board of the VXLAN switch, wherein, the multicast group member port indicates a port through which a connection to a multicast group member is established, and the first virtual port is a virtual switch port used by the I/O board to determine whether the fabric board continues to perform entry searching and multicast data packet forwarding; receiving, by the fabric board of the VXLAN switch, the multicast data packet sent by the I/O board; determining that layer 3 multicast forwarding is to be performed by the fabric board for the multicast data packet; searching, by the fabric board, a local layer 3 multicast group table for a layer 3 multicast group entry matching with a destination IP address and a destination MAC address of the multicast data packet; when a multicast group member port in the layer 3 multicast group entry corresponding to the multicast data packet is a VXLAN tunnel port, modifying a source MAC address of the multicast data packet as a gateway MAC address of the VXLAN switch; sending the multicast data packet with the modified source MAC address to an I/O board corresponding to the multicast group member port on the VXLAN switch, wherein, the VXLAN tunnel port is a virtual switch port associated with a VXLAN tunnel; and receiving, by the I/O board corresponding to the multicast group member port on the VXLAN switch, the multicast data packet sent by the fabric board; adding a VXLAN encapsulation to the multicast data packet and forwarding the multicast data packet having the VXLAN encapsulation to a VXLAN. receiving, by an I/O board of an Virtual eXtensible Local Area Network, VXLAN, switch, a multicast data packet from a Virtual Local Area Network, VLAN; searching, by the I/O board, a local layer 3 multicast group table for a layer 3 multicast group entry matching with a destination Internet Protocol, IP, address and a destination Media Access Control, MAC, address of the multicast data packet; when at least one multicast group member port in the layer 3 multicast group entry corresponding to the multicast data packet is a first virtual port, sending the multicast data packet to a fabric board of the VXLAN switch, wherein, the multicast group member port indicates a port through which a connection to a multicast group member is established, and the first virtual port is a virtual switch port used by the I/O board to determine whether the fabric board continues to perform entry searching and multicast data packet forwarding; receiving, by the fabric board of the VXLAN switch, the multicast data packet sent by the I/O board; determining that layer 3 multicast forwarding is to be performed by the fabric board for the multicast data packet; searching, by the fabric board, a local layer 3 multicast group table for a layer 3 multicast group entry matching with a destination IP address and a destination MAC address of the multicast data packet; when a multicast group member port in the layer 3 multicast group entry corresponding to the multicast data packet is a VXLAN tunnel port, modifying a source MAC address of the multicast data packet as a gateway MAC address of the VXLAN switch; sending the multicast data packet with the modified source MAC address to an I/O board corresponding to the multicast group member port on the VXLAN switch, wherein, the VXLAN tunnel port is a virtual switch port associated with a VXLAN tunnel; and receiving, by the I/O board corresponding to the multicast group member port on the VXLAN switch, the multicast data packet sent by the fabric board; adding a VXLAN encapsulation to the multicast data packet and forwarding the multicast data packet having the VXLAN encapsulation to a VXLAN.